Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Dakota Skipper and Poweshiek Skipperling, 63625-63745 [2013-24778]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 78, Number 206 (Thursday, October 24, 2013)]
[Proposed Rules]
[Pages 63625-63745]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-24778]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

[FWS-R3-ES-2013-0017; 4500030113]
RIN 1018-AZ58


Endangered and Threatened Wildlife and Plants; Designation of 
Critical Habitat for Dakota Skipper and Poweshiek Skipperling

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service, propose to designate 
critical habitat for the Dakota skipper and Poweshiek skipperling under 
the Endangered Species Act of 1973, as amended. The Endangered Species 
Act requires that critical habitat be designated to the maximum extent 
prudent and determinable for species determined to be endangered or 
threatened species. The effect of this regulation is to designate 
critical habitat for the Dakota skipper and Poweshiek skipperling under 
the Endangered Species Act.

DATES: Written Comments: We will accept comments received or postmarked 
on or before December 23, 2013. Comments submitted electronically using 
the Federal eRulemaking Portal (see ADDRESSES section, below) must be 
received by 11:59 p.m. Eastern Time on the closing date. We must 
receive requests for public hearings, in writing, at the address shown 
in ADDRESSES by December 9, 2013.
    Public Informational Meetings: To better inform the public of the 
implications of the proposed listing and to answer any questions 
regarding this proposed rule, we plan to hold five public informational 
meetings. We have scheduled informational meetings regarding the 
proposed rule in the following locations:
    (1) Minot, North Dakota, on November 5, 2013, at the Souris Valley 
Suites, 800 37th Avenue SW;
    (2) Milbank, South Dakota, on November 6, 2013, at the Milbank 
Chamber of Commerce, 1001 East 4th Avenue;
    (3) Milford, Iowa, on November 7, 2013, at the Iowa Lakeside 
Laboratory, 1838 Highway 86;
    (4) Holly, Michigan, on November 13, 2013, at the Rose Pioneer 
Elementary School, 7110 Milford Road; and
    (5) Berlin, Wisconsin, on November 14, 2013, at the Berlin Public 
Library, 121 West Park Avenue.
    Except for the meeting in Berlin, Wisconsin, each informational 
meeting will be from 5:30 p.m. to 8:00 p.m.; the meeting in Berlin, 
Wisconsin will be from 4:30 p.m. to 7:00 p.m.

ADDRESSES: You may submit comments by one of the following methods:
    (1) Electronically: Go to the Federal eRulemaking Portal: https://www.regulations.gov. In the Search box, enter FWS-R3-ES-2013-0017, 
which is the docket number for this rulemaking. You may submit a 
comment by clicking on ``Comment Now!'' If your comments will fit in 
the provided comment box, please use this feature of https://www.regulations.gov, as it is most compatible with our comment review 
procedures. If you attach your comments as a separate document, our 
preferred file format is Microsoft Word. If you attach multiple 
comments (such as form letters), our preferred format is a spreadsheet 
in Microsoft Excel.
    (2) By hard copy: Submit by U.S. mail or hand-delivery to: Public 
Comments

[[Page 63626]]

Processing, Attn: FWS-R3-ES-2013-0017; Division of Policy and 
Directives Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax 
Drive, MS 2042-PDM; Arlington, VA 22203.
    We request that you send comments only by the methods described 
above. We will post all comments on https://www.regulations.gov. This 
generally means that we will post any personal information you provide 
us (see the Public Comments section below for more information).
    The coordinates or plot points or both from which the maps are 
generated are included in the administrative record for this critical 
habitat designation and are available at (https://www.fws.gov/midwest/Endangered/), www.regulations.gov at Docket No. FWS-R3-ES-2013-0017, 
and at the Twin Cities Ecological Services Office (see FOR FURTHER 
INFORMATION CONTACT). Any additional tools or supporting information 
that we may develop for this critical habitat designation will also be 
available at the Fish and Wildlife Service Web site and Field Office 
set out above, and may also be included at https://www.regulations.gov.

FOR FURTHER INFORMATION CONTACT: Peter Fasbender, Field Supervisor, 
U.S. Fish and Wildlife Service, Twin Cities Ecological Services Office, 
4101 American Boulevard East, Bloomington, Minnesota 55425, by 
telephone 612-725-3548 or by facsimile 612-725-3609. Persons who use a 
telecommunications device for the deaf (TDD) may call the Federal 
Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION: 

Executive Summary

    Why we need to publish a rule. Under the Endangered Species Act 
(Act), any species that is determined to be a threatened or endangered 
species requires critical habitat to be designated, to the maximum 
extent prudent and determinable. Designations and revisions of critical 
habitat can only be completed by issuing a rule. Elsewhere in today's 
Federal Register, we propose to list the Dakota skipper (Hesperia 
dacotae) and Poweshiek skipperling (Oarisma poweshiek) as endangered 
species under the Act.
    This rule proposes to designate critical habitat for Dakota skipper 
and Poweshiek skipperling.
    We are proposing critical habitat for Dakota skipper and Poweshiek 
skipperling under the Act.
    Approximately 11,243 hectares (ha) (27,782 acres (ac)) are being 
proposed for designation as critical habitat for the Dakota skipper in 
Chippewa, Clay, Kittison, Lincoln, Murray, Norman, Pipestone, Polk, 
Pope, and Swift Counties in Minnesota; McHenry, McKenzie, Ransom, 
Richland, Rolette, and Wells Counties in North Dakota; and Brookings, 
Day, Deuel, Grant, Marshall, and Roberts Counties in South Dakota. 
Approximately 10,596 ha (26,184 ac) are being proposed for designation 
as critical habitat for the Poweshiek skipperling, in Cerro Gordo, 
Dickinson, Emmet, Howard, Kossuth, and Osceola Counties in Iowa; in 
Hilsdale, Jackson, Lenawee, Livingston, Oakland, and Washtenaw Counties 
in Michigan; Chippewa, Clay, Cottonwood, Douglas, La Qui Parle, 
Lincoln, Lyon, Mahnomen, Murray, Norman, Pipestone, Pope, Swift, and 
Wilkin Counties in Minnesota; Ransom, Richland, and Sargent Counties in 
North Dakota; Brookings, Day, Deuel, Grant, Marshall, Moody, and 
Roberts Counties in South Dakota; and Green Lake and Waukesha Counties 
in Wisconsin. In total, approximately 15,797 ha (39,035 ac) is being 
proposed as critical habitat for both species combined, as 
approximately 6,042 ha (14,931 ac) of proposed critical habitat is 
common to both species.
    The basis for our action. Under the Endangered Species Act, any 
species that is determined to be a threatened or endangered species 
shall, to the maximum extent prudent and determinable, have habitat 
designated that is considered to be critical habitat. Section 4(b)(2) 
of the Endangered Species Act states that the Secretary shall designate 
and make revisions to critical habitat on the basis of the best 
available scientific data after taking into consideration the economic 
impact, national security impact, and any other relevant impact of 
specifying any particular area as critical habitat. The Secretary may 
exclude an area from critical habitat if she determines that the 
benefits of such exclusion outweigh the benefits of specifying such 
area as part of the critical habitat, unless she determines, based on 
the best scientific data available, that the failure to designate such 
area as critical habitat will result in the extinction of the species.
    We are preparing an economic analysis of the proposed designations 
of critical habitat. In order to consider economic impacts, we are 
preparing an analysis of the economic impacts of the proposed critical 
habitat designations and related factors. We will announce the 
availability of the draft economic analysis as soon as it is completed, 
at which time we will seek additional public review and comment.
    We will seek peer review. We are seeking comments from independent 
specialists to ensure that our critical habitat proposal is based on 
scientifically sound data and analyses. We have invited these peer 
reviewers to comment on our specific assumptions and conclusions in 
this critical habitat proposal. Because we will consider all comments 
and information we receive during the comment period, our final 
determinations may differ from this proposal.

Information Requested

    We intend that any final action resulting from this proposed rule 
will be based on the best scientific and commercial data available and 
be as accurate and as effective as possible. Therefore, we request 
comments or information from other concerned government agencies, the 
scientific community, industry, or any other interested party 
concerning this proposed rule. We particularly seek comments 
concerning:
    (1) The reasons we should or should not designate habitat as 
``critical habitat'' under section 4 of the Act (16 U.S.C. 1531 et 
seq.), including whether there are threats to the species from human 
activity, the degree of which can be expected to increase due to the 
designation, and whether that increase in threat outweighs the benefit 
of designation such that the designation of critical habitat may not be 
prudent.
    (2) Specific information on:
    (a) The amount and distribution of Dakota skipper and Poweshiek 
skipperling habitat;
    (b) What areas, that were occupied at the time of listing (or are 
currently occupied) and that contain features essential to the 
conservation of the species, should be included in the designation and 
why;
    (c) Special management considerations or protection that may be 
needed in critical habitat areas we are proposing, including how to 
implement livestock grazing, haying, or prescribed fire in a manner 
that is conducive to the conservation of Dakota skipper or Poweshiek 
skipperling, and managing for the potential effects of climate change; 
and
    (d) What areas not occupied at the time of listing are essential 
for the conservation of the species and why.
    (3) Land use designations and current or planned activities in the 
subject areas and their possible impacts on proposed critical habitat.
    (4) Information on the projected and reasonably likely impacts of 
climate change on the Dakota skipper and

[[Page 63627]]

Poweshiek skipperling and proposed critical habitat.
    (5) Any probable economic, national security, or other relevant 
impacts of designating any area that may be included in the final 
designation; in particular, any impacts on small entities or families, 
and the benefits of including or excluding areas that exhibit these 
impacts.
    (6) Whether any specific areas we are proposing for critical 
habitat designation should be considered for exclusion under section 
4(b)(2) of the Act, and whether the benefits of potentially excluding 
any specific area outweigh the benefits of including that area under 
section 4(b)(2) of the Act. For instance, should the final designation 
exclude properties that are under conservation easement to the U.S. 
Fish and Wildlife Service or another conservation agency, or properties 
held by conservation organizations, and why? In addition, we are 
seeking information to better understand how the exclusion or inclusion 
of specific private lands in the final critical habitat designation 
would affect private landowner interest and acceptance of programs that 
are intended to conserve native grasslands in the range of Dakota 
skipper and Poweshiek skipperling. We seek any information relevant to 
potential exclusion of any proposed critical habitat unit, and 
particularly seek information relating to conservation programs or 
plans of any kind that may protect butterfly habitat on these units. 
Exclusion of any number of proposed critical habitat units, pursuant to 
section 4(b)(2) of the Act is within the range of possible decisions in 
the final rule.
    (7) Whether any specific Tribally-owned areas we are proposing for 
critical habitat designation should be considered for exclusion from 
final designation under section 4(b)(2) of the Act, and information 
regarding the management of those areas.
    (8) Whether we could improve or modify our approach to designating 
critical habitat in any way to provide for greater public participation 
and understanding, or to better accommodate public concerns and 
comments.
    Please include sufficient information with your submission (such as 
scientific journal articles or other publications) to allow us to 
verify any scientific or commercial information you include.
    Please note that submissions merely stating support for or 
opposition to the action under consideration without providing 
supporting information, although noted, will not be considered in 
making a determination, as section 4(b)(1)(A) of the Act directs that 
listing and critical habitat determinations must be made ``solely on 
the basis of the best scientific and commercial data available.''
    You may submit your comments and materials concerning this proposed 
rule by one of the methods listed in ADDRESSES. We request that you 
send comments only by the methods described in the ADDRESSES section.
    If you submit information via https://www.regulations.gov, your 
entire submission--including any personal identifying information--will 
be posted on the Web site. If your submission is made via a hardcopy 
that includes personal identifying information, you may request at the 
top of your document that we withhold this information from public 
review. However, we cannot guarantee that we will be able to do so. We 
will post all hardcopy submissions on https://www.regulations.gov. 
Please include sufficient information with your comments to allow us to 
verify any scientific or commercial information you include.
    Comments and materials we receive, as well as supporting 
documentation we used in preparing this proposed rule, will be 
available for public inspection on https://www.regulations.gov, or by 
appointment, during normal business hours, at the U.S. Fish and 
Wildlife Service, Twin Cities Ecological Services Office (see FOR 
FURTHER INFORMATION CONTACT).

Previous Federal Actions

    All previous Federal actions are described in the proposal to list 
the Dakota skipper as a threatened species and the Poweshiek 
skipperling as an endangered species under the Endangered Species Act 
published elsewhere in today's Federal Register.

Critical Habitat

Background

    For more information on Dakota skipper and Poweshiek skipperling 
taxonomy, life history, habitat, and population descriptions and our 
proposal to list the species under the Act, please refer to the 
proposed rule to list the species that is published elsewhere in 
today's Federal Register.
    It is our intent to discuss below only those topics directly 
relevant to the designation of critical habitat for the Dakota skipper 
and Poweshiek skipperling in this section of the proposed rule.
    Critical habitat is defined in section 3 of the Act as:
    (1) The specific areas within the geographical area occupied by the 
species, at the time it is listed in accordance with the Act, on which 
are found those physical or biological features
    (a) Essential to the conservation of the species and
    (b) Which may require special management considerations or 
protection; and
    (2) Specific areas outside the geographical area occupied by the 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    Conservation, as defined under section 3 of the Act, means to use 
and the use of all methods and procedures that are necessary to bring 
an endangered or threatened species to the point at which the measures 
provided pursuant to the Act are no longer necessary. Such methods and 
procedures include, but are not limited to, all activities associated 
with scientific resources management such as research, census, law 
enforcement, habitat acquisition and maintenance, propagation, live 
trapping, and transplantation, and, in the extraordinary case where 
population pressures within a given ecosystem cannot be otherwise 
relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the requirement that Federal agencies ensure, in consultation 
with the Service, that any action they authorize, fund, or carry out is 
not likely to result in the destruction or adverse modification of 
critical habitat. The designation of critical habitat does not affect 
land ownership or establish a refuge, wilderness, reserve, preserve, or 
other conservation area. Such designation does not allow the government 
or public to access private lands. Such designation does not require 
implementation of restoration, recovery, or enhancement measures by 
non-Federal landowners. Where a landowner requests Federal agency 
funding or authorization for an action that may affect a listed species 
or critical habitat, the consultation requirements of section 7(a)(2) 
of the Act would apply, but even in the event of a destruction or 
adverse modification finding, the obligation of the Federal action 
agency and the landowner is not to restore or recover the species, but 
to implement reasonable and prudent alternatives to avoid destruction 
or adverse modification of critical habitat.
    Under the first prong of the Act's definition of critical habitat, 
areas within the geographical area occupied by the species at the time 
it was listed

[[Page 63628]]

are included in a critical habitat designation if they contain physical 
or biological features (1) essential to the conservation of the species 
and (2) which may require special management considerations or 
protection. For these areas, critical habitat designations identify, to 
the extent known using the best scientific and commercial data 
available, those physical or biological features that are essential to 
the conservation of the species (such as space, food, cover, and 
protected habitat). In identifying those physical or biological 
features within an area, we focus on the principal biological or 
physical constituent elements (primary constituent elements such as 
roost sites, nesting grounds, seasonal wetlands, water quality, tide, 
soil type) that are essential to the conservation of the species. 
Primary constituent elements are the elements of physical or biological 
features that provide for a species' life-history processes, and are 
essential to the conservation of the species.
    Under the second prong of the Act's definition of critical habitat, 
we can designate critical habitat in areas outside the geographical 
area occupied by the species at the time it is listed, upon a 
determination that such areas are essential for the conservation of the 
species. For example, an area that was recently occupied, but not 
occupied at the time of listing, may be essential to the conservation 
of the species and may be included in the critical habitat designation. 
We designate critical habitat in areas outside the geographical area 
occupied by a species only when a designation limited to its range 
would be inadequate to ensure the conservation of the species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific data available. Further, our Policy on 
Information Standards Under the Endangered Species Act (published in 
the Federal Register on July 1, 1994 (59 FR 34271)), the Information 
Quality Act (section 515 of the Treasury and General Government 
Appropriations Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658)), 
and our associated Information Quality Guidelines, provide criteria, 
establish procedures, and provide guidance to ensure that our decisions 
are based on the best scientific data available. They require our 
biologists, to the extent consistent with the Act and with the use of 
the best scientific data available, to use primary and original sources 
of information as the basis for recommendations to designate critical 
habitat.
    When we are determining which areas should be designated as 
critical habitat, our primary source of information is generally the 
information developed during the listing process for the species. 
Additional information sources may include the recovery plan for the 
species, articles in peer-reviewed journals, conservation plans 
developed by States and counties, scientific status surveys and 
studies, biological assessments, other unpublished materials, or 
experts' opinions or personal knowledge.
    Habitat is dynamic, and species may move from one area to another 
over time. Climate change will be a particular challenge for 
biodiversity because the interaction of additional stressors associated 
with climate change and current stressors may push species beyond their 
ability to survive (Lovejoy 2005, pp. 325-326). The synergistic 
implications of climate change and habitat fragmentation are the most 
threatening facet of climate change for biodiversity (Hannah and 
Lovejoy 2005, p. 4). Current climate change predictions for terrestrial 
areas in the Northern Hemisphere indicate warmer air temperatures, more 
intense precipitation events, and increased summer continental drying 
(Field et al. 1999, pp. 1-3; Hayhoe et al. 2004, p. 12422; Cayan et al. 
2005, p. 6; Intergovernmental Panel on Climate Change (IPCC) 2007, p. 
1181). Climate change may lead to increased frequency and duration of 
severe storms and droughts (Golladay et al. 2004, p. 504; McLaughlin et 
al. 2002, p. 6074; Cook et al. 2004, p. 1015).
    We recognize that critical habitat designated at a particular point 
in time may not include all of the habitat areas that we may later 
determine are necessary for the recovery of the species. For these 
reasons, a critical habitat designation does not signal that habitat 
outside the designated area is unimportant or may not be needed for 
recovery of the species. Areas that are important to the conservation 
of the species, both inside and outside the critical habitat 
designation, will continue to be subject to: (1) Conservation actions 
implemented under section 7(a)(1) of the Act, (2) regulatory 
protections afforded by the requirement in section 7(a)(2) of the Act 
for Federal agencies to ensure their actions are not likely to 
jeopardize the continued existence of any endangered or threatened 
species, and (3) the prohibitions of section 9 of the Act if actions 
occurring in these areas may take the species. Federally funded or 
permitted projects affecting listed species outside their designated 
critical habitat areas may still result in jeopardy findings in some 
cases. These protections and conservation tools will continue to 
contribute to recovery of this species. Similarly, critical habitat 
designations made on the basis of the best available information at the 
time of designation will not control the direction and substance of 
future recovery plans, habitat conservation plans (HCPs), or other 
species conservation planning efforts if new information available at 
the time of these planning efforts calls for a different outcome.

Prudency Determination

    Section 4(a)(3) of the Act, as amended, and implementing 
regulations (50 CFR 424.12), require that, to the maximum extent 
prudent and determinable, the Secretary shall designate critical 
habitat at the time the species is determined to be an endangered or 
threatened species. Our regulations (50 CFR 424.12(a)(1)) state that 
the designation of critical habitat is not prudent when one or both of 
the following situations exist:
    (1) The species is threatened by taking or other human activity, 
and identification of critical habitat can be expected to increase the 
degree of threat to the species, or
    (2) such designation of critical habitat would not be beneficial to 
the species.
    There is currently no immediate threat of take attributed to 
collection or vandalism (see the Summary of Factors Affecting the 
Species section of the proposed listing rule published elsewhere in 
today's Federal Register) for either the Dakota skipper or Poweshiek 
skipperling, and identification and mapping of critical habitat is not 
expected to initiate any such threat. In the absence of finding that 
the designation of critical habitat would increase threats to a 
species, if there are any benefits to a critical habitat designation, 
then a prudent finding is warranted. Here, the potential benefits of 
designation include: (1) Triggering consultation under section 7 of the 
Act, in new areas for actions in which there may be a Federal nexus 
where it would not otherwise occur because, for example, it is or has 
become unoccupied or the occupancy is in question; (2) focusing 
conservation activities on the most essential features and areas; (3) 
providing educational benefits to State or county governments or 
private entities; and (4) preventing people from causing inadvertent 
harm to the species. Therefore, because we have determined that the 
designation of critical habitat will not likely increase the degree of 
threat to the Dakota

[[Page 63629]]

skipper or Poweshiek skipperling and may provide some measure of 
benefit, we find that designation of critical habitat is prudent for 
the Dakota skipper and Poweshiek skipperling.

Critical Habitat Determinability

    Having determined that designation is prudent, under section 
4(a)(3) of the Act we must find whether critical habitat for the Dakota 
skipper and Poweshiek skipperling is determinable. Our regulations at 
50 CFR 424.12(a)(2) state that critical habitat is not determinable 
when one or both of the following situations exist:
    (i) Information sufficient to perform required analyses of the 
impacts of the designation is lacking, or
    (ii) The biological needs of the species are not sufficiently well 
known to permit identification of an area as critical habitat.
    When critical habitat is not determinable, the Act allows the 
Service an additional year to publish a critical habitat designation 
(16 U.S.C. 1533(b)(6)(C)(ii)).
    We reviewed the available information pertaining to the biological 
needs of the species and habitat characteristics where these species 
are located. This and other information represent the best scientific 
data available and led us to conclude that the designation of critical 
habitat is determinable for the Dakota skipper and Poweshiek 
skipperling.

Physical or Biological Features

    In accordance with section 3(5)(A)(i) and regulations at 50 CFR 
424.12(b), in determining which areas within the geographical area 
occupied by the species at the time of listing to designate as critical 
habitat, we consider the physical or biological features that are 
essential to the conservation of the species and which may require 
special management considerations or protection. These include, but are 
not limited to:
    (1) Space for individual and population growth and for normal 
behavior;
    (2) Food, water, air, light, minerals, or other nutritional or 
physiological requirements;
    (3) Cover or shelter;
    (4) Sites for breeding, reproduction, or rearing (or development) 
of offspring; and
    (5) Habitats that are protected from disturbance or are 
representative of the historical geographic and ecological 
distributions of a species.

Dakota Skipper

    We derived the specific physical or biological features required 
for the Dakota skipper from studies of the species' habitat, ecology, 
and life history as described below. Additional information can be 
found in the Background section of the proposed listing rule, published 
elsewhere in today's Federal Register. We have determined that the 
following physical or biological features are essential for the Dakota 
skipper:
Space for Individual and Population Growth and for Normal Behavior
    Dakota skippers are obligate residents of remnant (untilled) high-
quality prairie--habitats that are dominated by native grasses and that 
contain a high diversity of native forbs (flowering herbaceous plants). 
Dakota skipper habitat has been categorized into two main types: Type A 
habitat is described as high-quality, low (wet-mesic) prairie with 
little topographic relief that occurs on near-shore glacial lake 
deposits, dominated by little bluestem grass (Schizachyrium scoparium), 
with the likely presence of wood lily (Lilium philadelphicum), bluebell 
bellflower (Campanula rotundifolia), and mountain deathcamas (smooth 
camas; Zigadenus elegans) (McCabe 1981, p. 190; Royer and Marrone 
1992a, pp. 8, 14-16, 21). Type B habitat is described as rolling 
native-prairie terrain over gravelly glacial moraine deposits and is 
dominated by bluestems and needle-grasses (e.g., Hesperostipa spartea) 
with the likely presence of bluebell bellflower, wood lily, purple 
coneflower (Echinacea angustifolia), upright prairie coneflower 
(Ratibida columnifera), and common gaillardia (Gaillardia aristata) 
(Royer and Marrone 1992a, pp. 21-22).
    Dry prairies are described to have a sparse shrub layer (less than 
5 percent cover) composed mainly of leadplant (Amorpha canescens), with 
prairie rose (Rosa arkansana) and wormwood sage (Artemisia frigida) 
often present (Minnesota Department of Natural Resources 2012a, p. 1). 
Taller shrubs, such as smooth sumac (Rhus glabra), may also be present. 
Occasional trees, such as bur oak (Quercus macrocarpa) or black oak 
(Quercus velutina), may also be present but remain less than 
approximately 5 percent cover (Minnesota Department of Natural 
Resources 2012a, p. 1). Similarly, wet-mesic prairies are described to 
have a sparse shrub layer (less than 5 to 25 percent cover) of 
leadplant, prairie rose, wolfberry (Symphoricarpos occidentalis), and 
other native shrubs such as gray dogwood (Cornus racemosa), American 
hazelnut (Corylus americana), and wild plum (Prunus americana) 
(Minnesota Department of Natural Resources 2012b, p. 1). Therefore, 
based on the information above, we identify high-quality Type A or Type 
B native remnant (untilled) prairie, as described above, containing a 
mosaic of native grasses and flowering forbs and sparse shrub and tree 
cover to be a physical or biological feature essential to the 
conservation of the Dakota skipper.
    Nonnative invasive plant species, such as Kentucky bluegrass (Poa 
pratensis) and smooth brome (Bromus inermus) may outcompete native 
plants that are necessary for the survival of Dakota skipper and lead 
to the deterioration or elimination of native vegetation. Dakota 
skipper depend on a diversity of native plants endemic to tallgrass and 
mixed-grass prairies; therefore, when nonnative or woody plant species 
become dominant, Dakota skipper populations decline due to insufficient 
sources of larval food and nectar for adults. Therefore, native 
prairies, as described above, with an absence or only sparse presence 
of nonnative invasive plant species is a physical or biological feature 
essential to the conservation of the Dakota skipper.
    Royer and Marrone (1992a, p. 25) concluded that Dakota skippers are 
``not inclined to dispersal,'' although they did not describe 
individual ranges or dispersal distances. Concentrated activity areas 
for Dakota skippers shift annually in response to local nectar sources 
and disturbance (McCabe 1979, p. 9; 1981, p. 186). Marked adults moved 
across less than 200 meters (m) (656 feet (ft)) of unsuitable habitat 
between two prairie patches and moved along ridges more frequently than 
across valleys (Dana 1991, pp. 37-38). Average movements of recaptured 
adults were less than 300 m (984 ft) over 3-7 days. Dana (1997, p. 6) 
later observed reduced movement rates across a small valley with roads 
and crop fields compared with movements in adjacent widespread prairie 
habitat.
    Dakota skipper are not known to disperse widely and have low 
mobility; experts estimate Dakota skipper has a mean mobility of 3.5 
(standard deviation = 0.71) on a scale of 0 (sedentary) to 10 (highly 
mobile) (Burke et al. 2011, Fitzsimmons 2012, pers. comm.). Five Dakota 
skipper experts interviewed in 2001 indicated that it was unlikely that 
Dakota skippers were capable of moving greater than 1 kilometer (km) 
(0.6 miles (mi)) between patches of prairie habitat separated by 
structurally similar habitats (e.g., perennial grassland, but not 
necessarily native prairie) (Cochrane and Delphey 2002, p. 6). The 
species will not likely disperse across unsuitable habitat, such

[[Page 63630]]

as certain types of row crops (e.g., corn, beets), or anywhere not 
dominated by grasses. Skadsen (1999, p. 2) reported possible movement 
of unmarked Dakota skippers from a known population at least 800 m 
(2,625 ft) away to a site with an unusually heavy growth of purple 
coneflower where he had not found Dakota skippers in three previous 
years when coneflower production was sparse. The two sites were 
connected by ``native vegetation of varying quality'' with a few 
asphalt and gravel roads interspersed (Skadsen in litt. 2001).
    Dakota skipper may move in response to local nectar sources, 
disturbance, or in search of a mate. The tallgrass prairie that once 
made up a vast ecosystem prior to European settlement has now been 
reduced to fragmented remnants that make up less than 1 to 15 percent 
of the original land area across the species' range (Samson and Knopf 
1994, p. 419). Similarly, mixed-grass prairie has been reduced to 
fragmented remnants that make up less than 1, 19, and 28 percent of the 
original land area in Manitoba, Saskatchewan, and North Dakota, 
respectively (Samson and Knopf 1994, p. 419). Before the range-wide 
fragmentation of prairie habitat, the species could move freely across 
suitable tallgrass and mixed-grass prairie and between high-quality 
prairies through suitable dispersal habitat. Now, these fragmented 
populations need immigration corridors for dispersal from nearby 
populations to prevent genetic drift and perhaps to reestablish a 
population after local extirpation. Therefore, based on the information 
above, we identify undeveloped dispersal habitat, structurally similar 
to suitable high-quality prairie habitat, as described above, to be a 
physical or biological feature essential to the conservation of the 
Dakota skipper. These dispersal habitats should be adjacent to or 
between high-quality prairie patches and within the known dispersal 
distance of Dakota skipper; within 1 km (0.6 mi) from suitable high-
quality Type A or Type B prairie and should have limited shrub and tree 
cover, and no or limited amounts of certain row crops, which may act as 
barriers to dispersal.
    In summary, we identify high-quality wet-mesic or dry (Type A and 
Type B) remnant (untilled) prairie containing a mosaic of native 
grasses and flowering forbs to be a physical or biological feature 
necessary to allow for normal behavior and population growth of Dakota 
skipper. Both wet-mesic and dry prairies have limited tree and low 
shrub coverage that may act as barriers to dispersal and limited or no 
invasive plant species that may lead to a change in the plant 
community. Dispersal habitat, structurally similar to suitable high 
quality prairie habitat and adjacent to or between high-quality prairie 
patches should be located within the known dispersal distance of Dakota 
skipper (within 1 km (0.6 miles) from suitable high-quality Type A or 
Type B prairie) to help maintain genetic diversity and to provide 
refuges from disturbance.
Food, Water, Air, Light, Minerals, or Other Nutritional or 
Physiological Requirements
    Dakota skipper larvae feed only on a few native grass species; 
little bluestem is a frequent food source (Dana 1991, p. 17; Royer & 
Marrone 1992a, p. 25), although they have also been found on Panicwn 
spp., Poa spp., and other native grasses (Royer and Marrone 1992a, p. 
25). Seasonal senescence patterns (timing of growth) of grass species 
relative to the larval period of Dakota skippers are likely important 
in determining the suitability of grass species as larval host plants 
because warm-season grasses such as little bluestem grow and stay green 
and palatable from June through early September, the months when Dakota 
skipper larvae are feeding (NRCS 2004, p. 1). By contrast, cool-season 
grasses such as the nonnative Kentucky bluegrass grow during the cooler 
spring and fall (NRCS 2004, p. 1), and are, therefore, not available 
during the larval period of Dakota skipper. Consequently, based on the 
information above, we identify native grass species, such as little 
bluestem, to be a physical or biological feature essential to the 
conservation of the Dakota skipper. These native grasses should be 
available during the larval stage of Dakota skipper.
    Adult Dakota skippers may use several species of native forbs as 
nectar sources, which can vary regionally. Examples of adult nectar 
sources include: Purple coneflower, bluebell bellflower, white prairie 
clover (Dalea candida), upright prairie coneflower, fleabanes (Erigeron 
spp.), blanketflowers (Gaillardia spp.), black-eyed Susan, yellow 
sundrops (Calylophus serrulatus), groundplum milkvetch (Astragalus 
crassicarpus), deathcamas (smooth camas), common primrose, and tooth-
leaved primrose (Calylophus serrulata) (McCabe and Post 1977b, p. 36, 
McCabe 1979, p. 42, 1981, p. 187, Royer and Marrone 1992a, p. 21, 
Swengel and Swengel 1999, pp. 280-281). Plant species likely vary in 
their value as nectar sources for Dakota skipper due to the amount of 
nectar available to the species during the adult flight period (Dana 
1991, p. 48). Swengel and Swengel (1999, pp. 280-281) observed 
nectaring at 25 plant species, but 85 percent of the observations were 
at the following three taxa, in declining order of frequency: Purple 
coneflower, blanketflower, and groundplum milkvetch. Dana (1991, p. 21) 
reported the use of 25 nectar species in Minnesota with purple 
coneflower most frequented. Flowering forbs also provide water 
necessary to avoid desiccation (drying out) during the flight period 
(Dana 2013, pers. comm.). Therefore, based on the information above, we 
identify the availability of native nectar plant species, including but 
not limited to, those listed above to be a physical or biological 
feature for this species. These nectar plant species should be 
flowering during the Dakota skipper's adult flight period.
    Dakota skipper larvae are vulnerable to desiccation during hot, dry 
weather, and this vulnerability may increase in the western parts of 
the species' range (Royer et al. 2008, p. 15). Compaction of soils in 
the mesic and relatively flat Type A habitats may alter vertical water 
distribution and lead to decreased relative humidity levels near the 
soil surface (Gardiner and Miller 2007, pp. 36-40, 510-511; Frede 1985 
in Royer 2008, p. 2), which would further increase the risk of 
desiccation (Royer 2008, p. 2). Soils associated with dry and wet-mesic 
prairies are described as having a seasonally high water table and 
moderate to high permeability. Soil textures in Dakota skipper habitats 
are classified as loam, sandy loam, or loamy sand (Royer and Marrone 
1992b, p. 15, Skadsen 1997, Lenz 1999, pp. 4-5, 8, Swengel and Swengel 
1999, p. 282); soils in moraine deposits are described as gravelly, but 
the deposits associated with glacial lakes are not described as 
gravelly. The native-prairie grasses and flowering forbs detailed in 
the above sections are typically found on these soil types (Lenz 1999, 
pp. 4-5, 8), and plant species diversity is generally higher in remnant 
prairies where the soils have never been plowed (Higgins et al. 2000, 
pp. 23-24). Cultivation changes the physical state of the soil, 
including changes to bulk density (compaction), which may hinder seed 
germination and root growth (Tomko and Hall 1986, pp. 173-175; Miller 
and Gardiner 2007, pp. 510-511). Furthermore, certain native prairie 
plants are found only in prairies that lack a tillage history (Higgins 
et al. 2000, p. 23). Finally, bulk density affects plant growth 
(Gardiner and Miller 2008, p. 36) and, therefore, can alter the plant 
community. For example, Dakota

[[Page 63631]]

skippers appear to be generally absent from Type A habitat in North 
Dakota when it is grazed due to a shift away from a plant community 
that is suitable for the species (McCabe 1979, p. 17; McCabe 1981, p. 
179). The shift in plant community composition may occur rapidly 
(McCabe 1981, p. 179; Royer and Royer 1998, p. 23).
    Therefore, we identify loam, sandy loam, loamy sand, or gravelly 
soils that have never been plowed or tilled to be a physical feature 
essential to the conservation of the Dakota skipper.
    In summary, the biological features that provide food sources 
include native grass species for larval food, such as little bluestem 
and prairie dropseed, and native forb plant species for adult nectar 
sources, such as purple coneflower, bluebell bellflower, white prairie 
clover, upright prairie coneflower, fleabanes, blanketflowers, black-
eyed Susan, and groundplum milkvetch. These prairies have undisturbed 
(untilled) edaphic (related to soil) features that are conducive to the 
development and survival of larval Dakota skipper and soil textures 
that are loam, sandy loam, loamy sand, or gravelly.
Cover or Shelter
    Dakota skippers oviposit (lay eggs) on broadleaf plants such as 
Astragalus spp. (McCabe 1981, p. 180) and grasses such as little 
bluestem, big bluestem (Andropogon gerardii), sideoats gramma, prairie 
dropseed, porcupine grass (Hesperostipa spartea), and Wilcox's Panic 
Grass (Dichanthelium wilcoxianum) (Dana 1991, p. 17). After hatching, 
Dakota skipper larvae crawl to the bases of grasses where they form 
shelters at or below the ground surface with silk fastened together 
with plant tissue (Dana 1991, p. 16). Dakota skippers overwinter in 
their ground-level or subsurface shelters during either the fourth or 
fifth instar (Dana 1991, p. 15; McCabe 1979, p. 6; 1981; Royer & 
Marrone 1992a, pp. 25-26). In the spring, larvae resume feeding and 
undergo two additional molts before they pupate. During the last two 
instars, larvae shift from buried shelters to horizontal shelters at 
the soil surface (Dana 1991, p. 16). Therefore, sufficient availability 
of grasses used to form shelters at or below the ground surface is a 
physical or biological feature essential for cover and shelter for 
Dakota skipper larvae.
    As discussed above, Dakota skipper larvae are vulnerable to 
desiccation (drying out) during hot, dry weather; this vulnerability 
may increase in the western parts of the species' range (Royer et al. 
2008, p. 15). Compaction of soils in the mesic and relatively flat Type 
A habitats may alter vertical water distribution and lead to decreased 
relative humidity levels near the soil surface, Gardiner and Miller 
2007, pp. 36-40, 510-511; Frede 1985 in Royer 2008, p. 2), which would 
further increase the risk of desiccation (Royer 2008, p. 2). Soils 
associated with wet-mesic prairies are described as having a seasonally 
high water table and moderate to high permeability (Lenz 1999, pp. 4-
5). Cultivation changes the physical state of soil (Tomko and Hall 
1986, pp. 173-175; Gardiner and Miller 2007, pp. 510-511), by, for 
example, changes to bulk density (compaction) that result in slower 
water movement through the soil (e.g., Tomko and Hall 1986, pp. 173-
175). Furthermore, because Dakota skipper spend a portion of their 
larval stage underground, the soil must remain undisturbed (untilled) 
during that time. Therefore, we identify untilled glacial soils 
including, but not limited to, loam, sandy loam, loamy sand, or 
gravelly soils to be a physical feature essential to the conservation 
of the Dakota skipper.
Sites for Breeding, Reproduction, or Rearing (or Development) of 
Offspring
    The annual, single generation of adult Dakota skippers emerges from 
mid-June to early July, depending on the weather, with flights starting 
earlier farther west in the range (McCabe 1979, p. 6, 1981, p. 180, 
Dana 1991, p. 1, Royer and Marrone 1992a, p. 26, Skadsen 1997, p. 3, 
Swengel and Swengel 1999, p. 282). During this time, adult male Dakota 
skippers typically perch on tall grasses and forbs, and occasionally 
appear to patrol in search of mating opportunities (Royer and Marrone 
1992a, p. 25). Therefore, the physical or biological features essential 
to the conservation of the Dakota skipper include above-ground parts of 
grasses and forbs for perching that are available during the adult 
flight period.
    The local flight period lasts two to four weeks and mating occurs 
throughout this period (McCabe 1979, p. 6, 1981, p. 180, Dana 1991, p. 
15). Adults are thought to disperse a maximum of 1.0 mi (1.6 km) in 
search of a mate or nectar sources (Cochrane and Delphey 2002, p. 6). 
During this time, adult Dakota skippers depend on nectar plants for 
food and water. Therefore, it is important that nectar plants are 
available in close proximity to areas suitable for oviposition and 
larval feeding.
    Dakota skippers lay eggs on broadleaf plants such as Astragalus 
spp. (McCabe 1981, p. 180) and grasses such as little bluestem, big 
bluestem (Andropogon gerardii), sideoats gramma, prairie dropseed, 
porcupine grass (Hesperostipa spartea), and Wilcox's Panic Grass 
(Dichanthelium wilcoxianum) (Dana 1991, p. 17), although larvae feed 
only on native grasses, such as little bluestem (Dana 1991, p. 17; 
Royer and Marrone 1992a, p. 25) and prairie dropseed (Royer and Marrone 
1992a, p. 25). After hatching, Dakota skipper larvae crawl to the bases 
of grasses where they form shelters at or below the ground surface 
(Dana 1991, p. 16) and emerge at night from their shelters to forage 
(McCabe 1979, p. 6, 1981, p. 181, Royer and Marrone 1992a, p. 25). 
Dakota skippers overwinter in their ground-level or subsurface shelters 
during either the fourth or fifth instar (McCabe 1979, p. 6, 1981, p. 
181, Dana 1991, p. 15, Royer and Marrone 1992a, pp. 25-26). In the 
spring, larvae resume feeding and undergo two additional molts before 
they pupate. During the last two instars, larvae shift from buried 
shelters to horizontal shelters at the soil surface (Dana 1991, p. 16). 
Therefore, the physical or biological features essential to the 
conservation of the Dakota skipper include above- and below-ground 
parts of grasses for oviposition and larval shelters and foraging; 
these grasses should be in close proximity to nectar plants where the 
adults are feeding during the short flight period.
    Dakota skipper larvae spend most of the summer at or near the soil 
surface (McCabe 1981, p. 181, Dana 1991, p. 15), therefore, biological 
factors such as availability of nectar and larval food sources, edaphic 
features such as bulk density (an indicator of soil compaction) and 
soil moisture, as well as related non-biotic factors such as 
temperature and relative humidity at and near (to a 2.0 cm depth; 0.79 
in) the soil surface may limit the survival of the sensitive larval and 
pupal stages of Dakota skippers (Royer et al. 2008, p. 2). Soil 
evaporation rates in the north-central United States are substantially 
affected by microtopography (variations of the soil surface on a small 
scale) (Cooper 1960 in Royer et al. 2008, p. 2). For example, removal 
of vegetation due to heavy livestock grazing, plowing, fire, and soil 
compaction alters evaporation and water movement through the soil, 
thereby altering the humidity of soil near the surface (e.g., Tomko and 
Hall 1986, pp. 173-175; Zhao et al. 2010, pp. 93-96), although the 
timing and intensity of these operations may affect the results. 
Livestock grazing can increase soil bulk density (an indicator of soil 
compaction) (Greenwood et al. 1997, pp. 413, 416-418; Gardiner and

[[Page 63632]]

Miller 2007, pp. 510-511; Zhao et al. 2007, p. 248), particularly when 
the soil is wet (Gardiner and Miller 2008, p. 510), and these increases 
have been correlated with decreased soil water content and movement of 
water through the soil (Zhao et al. 2007, p. 248). The loss of porosity 
results in higher bulk densities, thereby decreasing water movement 
through the soil (Warren et al. 1986, pp. 493-494).
    Similarly, vehicle traffic (including tilling and harvesting) 
increases compaction (Gardiner and Miller 2008, pp. 36, 510), and 
tilled land increases bulk densities (e.g., Tomko and Hall 1986, pp. 
173-175). During the hot and dry summer months, these changes in the 
soil restrict the movement of shallow groundwater to the soil surface, 
thus resulting in a dry soil layer during the time when Dakota skipper 
larvae are vulnerable to desiccation (Royer et al. 2008, p. 2). 
Furthermore, bulk density affects plant growth (Gardiner and Miller 
2008, p. 36) and, therefore, can alter the plant community. For 
example, Dakota skippers appear to be generally absent from Type A 
habitat in North Dakota when it is grazed due to a shift away from a 
plant community that is suitable for the species (McCabe 1979, p. 17; 
McCabe 1981, p. 179). The shift in plant community composition and 
adverse effects to Dakota skipper populations may occur rapidly (McCabe 
1981, p. 179; Royer and Royer 1998, p. 23).
    The following are acceptable levels for microclimatological 
(climate in a small space, such as at or near the soil surface) 
variables between the soil surface and 2.0 cm (0.79 in) deep throughout 
the range of Dakota skippers during the summer season (from when eggs 
are laid through when larvae enter diapause near the end of September); 
mean temperature range of 17.8 to 20.5 [deg]C (64.0 to 68.9 [deg]F), 
mean dew point ranging from 13.9 to 16.8 [deg]C (57.0 to 62.2 [deg]F), 
and mean relative humidity between 72.5 and 85.1 percent (Royer 2008, 
pp. 7, 14-15). Type A habitats, as discussed above, are topographically 
of low relief (little change in elevation) (less than l m (3.2 ft)), 
with sandy soils that are relatively free of gravel at least to depths 
of 60 cm (23.6 in) and nearly saturated at depths between 40 and 60 cm 
(15.7 to 23.6 in). In these habitat types, soil bulk density exceeds 
1.0 gram/cubic centimeter (g/cm\3\) (0.8 ounce/cubic inch (oz/in\3\) 
(Royer et al. 2008, p. 14). Type A habitat has a high water table (0.3 
to 1.8 m (1 to 6 ft)) and is subject to intermittent flooding in the 
spring, but provides some habitat that is not flooded during the spring 
larval growth period (Royer et al. 2008, p. 15). Bulk density at Dakota 
skipper sites (including Type A and Type B habitats) ranged from 
approximately 0.9 g/cm\3\ to 1.3 g/cm\3\ (0.5 oz/in\3\ to 0.7 oz/
in\3\), bulk density in Type A habitat ranged from 1.0 g/cm\3\ to 1.3 
g/cm\3\ (0.6 oz/in\3\ to 0.7 oz/in\3\), whereas mean bulk densities in 
Type B habitat are below 1.0g/cm\3\ (0.8 oz/in\3\) (Royer et al. 2008, 
p. 10). The gravelly soils of type B habitats are considerably more 
compact at all depths than the bulk density of Type A habitat, perhaps 
due to the presence of gravel and its effect on the accuracy of the 
instrument (Royer 2008, p. 15). Soil textures in Dakota skipper Type A 
habitats are classified as loam, sandy loam, or loamy sand (Royer et 
al. 2008, pp. 3-5, 14-15). Type B habitats are associated with gravelly 
glacial landscapes of predominantly sandy loams and loamy sand soils 
with relatively higher relief, more variable soil moisture, and 
slightly higher soil temperatures than Type A habitats (Royer et al. 
2008, p. 15).
    Edaphic features that allow for micro-climate (between the soil 
surface and 2.0 cm (0.8 in) deep) conditions that are conducive to 
Dakota skipper larvae survival during the summer months include, 
specifically, mean summer temperatures from 17.8 to 20.5 [deg]C (64.0 
to 68.9 [deg]F), mean dew point ranging from 13.9 to 16.8 [deg]C (57.0 
to 62.2 [deg]F), mean relative humidity between 72.5 and 85.1 percent, 
and bulk densities between 0.86 g/cm\3\ and 1.28 g/cm\3\ (0.5 oz/in\3\ 
to 0.74 oz/in\3\). These microclimatological levels are characteristic 
of untilled glacial soils. Furthermore, as described above, intensive 
livestock grazing can increase soil bulk density (an indicator of soil 
compaction)--the effects of grazing are dependent on the intensity and 
timing of grazing and soil type. The increases in soil bulk density 
increases have been correlated with decreased soil water content and 
movement of water through the soil. Therefore, untilled glacial soils 
that are not subject to intensive grazing pressure are physical or 
biological features essential to the conservation of the Dakota 
skipper.
Habitats Protected From Disturbance or Representative of the 
Historical, Geographic, and Ecological Distributions of the Species
    The Dakota skipper has a restricted geographic distribution. 
Species whose populations exhibit a high degree of isolation are 
extremely susceptible to extinction from both random and nonrandom 
catastrophic natural or human-caused events. Therefore, it is essential 
to maintain the native tallgrass prairies and native mixed-grass 
prairies upon which the Dakota skipper depends. This means protection 
from destruction or conversion, disturbance caused by exposure to land 
management actions (e.g., intense grazing, fire management, early 
haying, and herbicide or pesticide use), flooding, lack of management, 
and nonnative species that may degrade the availability of native 
grasses and flowering forbs. The Dakota skipper must, at a minimum, 
sustain its current distribution for the species to continue to 
persist. Introduced nonnative species are a serious threat to native 
tallgrass prairies and native mixed-grass prairies on which Dakota 
skipper depends ((Orwig 1997, pp. 4 and 8, Skadsen 2002, p. 52, Royer 
and Royer 2012b, p. 15-16, 22-23); see both Factor C: Disease and 
Predation, and Factor E: Other Natural or Manmade Factors Affecting Its 
Continued Existence sections of our proposed listing rule published 
elsewhere in today's Federal Register). Because the distribution of the 
Dakota skipper is isolated and its habitat so restricted, introduction 
of certain nonnative species into its habitat could have significant 
negative consequences. Dakota skipper typically occur at sites embedded 
in agricultural or developed landscapes, which makes them more 
susceptible to nonnative or woody plant invasion.
    Potentially harmful nonnative species include leafy spurge 
(Euphorbia esula), Kentucky bluegrass, alfalfa (Medicago sativa), 
glossy buckthorn (Frangula alnus), smooth brome, purple loosestrife 
(Lythrum salicaria), Canada thistle (Cirsium arvense), reed canary 
grass (Phalaris arundinacea), gray dogwood (Cornus racemosa), and 
others (Orwig 1997, pp. 4 and 8, Skadsen 2002, p. 52, Royer and Royer 
2012b, pp. 15-16, 22-23). Once these plants invade a site, they replace 
or reduce the coverage of native forbs and grasses used by adults and 
larvae of both butterflies. Leafy spurge displaces native plant species 
and its invasion is facilitated by actions that remove native plant 
cover and expose mineral soil (Belcher and Wilson 1989, p. 172). The 
threat from nonnative invasive species is compounded by the 
encroachment of native woody species into native-prairie habitat. 
Invasion of tallgrass and mixed-grass prairie by woody vegetation such 
as glossy buckthorn reduces light availability, total plant cover, and 
the coverage of grasses and sedges (Fiedler and Landis 2012, pp. 44, 
50-51). This in turn reduces the availability of both nectar and larval 
host plants for Dakota skipper.
    Dakota skippers are obligate residents of undisturbed high-quality 
prairie,

[[Page 63633]]

ranging from wet-mesic tallgrass prairie to dry-mesic mixed-grass 
prairie (Royer and Marrone 1992a, pp. 8, 21). High-quality prairie 
contains a high diversity of native species, including flowering 
herbaceous species (forbs). Degraded habitat consists of a high 
abundance of nonnative plants, woody vegetation, and a low abundance of 
native grasses and flowering forbs available during the larval growth 
period and a low abundance of native flowering forbs available during 
adult nectaring periods. Intensive grazing or fire management 
practices, early haying, flooding, as well as lack of management create 
such degraded habitats. Conversion to agriculture or other development 
also degrades or destroys native-prairie habitat. Therefore, based on 
the information above, we identify the necessary physical or biological 
features for the Dakota skipper as nondegraded native tallgrass prairie 
and native mixed-grass prairie habitat devoid of nonnative plant 
species, or habitat in which nonnative plant species and nonnative 
woody vegetation are at levels that allow persistence of Dakota 
skipper.

 Poweshiek Skipperling

    We derived the specific physical or biological features required 
for the Poweshiek skipperling from studies of the species' habitat, 
ecology, and life history as described below. Additional information 
can be found in the Background section of the proposed listing rule, 
published elsewhere in today's Federal Register. We have determined 
that the following physical or biological features are essential for 
the Poweshiek skipperling:
Space for Individual and Population Growth and for Normal Behavior
    The full range of habitat preferences for Poweshiek skipperling 
includes high-quality prairie fens, grassy lake and stream margins, 
remnant moist meadows, and wet-mesic to dry tallgrass remnant 
(untilled) prairies. These areas are dominated by native-prairie 
grasses, such as little bluestem and prairie dropseed (Sporobolus 
heterolepis), but also contain a high diversity of native forbs, 
including black-eyed Susan (Rudbeckia hirta) and palespike lobelia 
(Lobelia spicata). The disjunct populations of Poweshiek skipperling in 
Michigan occur in prairie fens, specifically, in peat domes within 
larger prairie fen complexes in areas co-dominated by mat muhly 
(Muhlenbergia richardsonis) and prairie dropseed (Cuthrell 2011, pers. 
comm.).
    Dry prairies are described to have a sparse shrub layer (less than 
5 percent of cover) composed mainly of leadplant, with prairie rose and 
wormwood sage often present (Minnesota Department of Natural Resources 
2012a, p. 1). Taller shrubs, such as smooth sumac, may also be present. 
Occasional trees, such as bur oak or black oak, may also be present but 
remain less than 5 percent cover (Minnesota Department of Natural 
Resources 2012a, p. 1). Similarly, wet-mesic prairies are described to 
have a sparse shrub layer (less than 5-25 percent cover) of leadplant, 
prairie rose, wolfberry, and other native shrubs such as gray dogwood, 
American hazelnut, and wild plum (Minnesota Department of Natural 
Resources 2012b, p. 1).
    Nonnative invasive plant species, such as Kentucky bluegrass and 
smooth brome, may outcompete native plants that are necessary for the 
survival of Poweshiek skipperling and lead to the deterioration or 
elimination of native vegetation. Poweshiek skipperling depend on a 
diversity of native plants endemic to tallgrass prairies and prairie 
fens; therefore, when nonnative or woody plant species become dominant, 
Poweshiek skipperling populations decline due to insufficient sources 
of larval food and nectar for adults. Therefore, native prairies as 
defined above, with an absence or only sparse presence of nonnative 
invasive plant species is a physical or biological feature essential to 
the conservation of the Poweshiek skipperling.
    The vegetative structure of prairie fens is a result of their 
unique hydrology and consists of plants that thrive in wetlands and 
calcium-rich soils mixed with tallgrass prairie and sedge meadow 
species (Michigan Natural Features Inventory 2012, p. 1). Three or four 
vegetation zones are often present in prairie fens, including diverse 
sedge meadows, wooded fen often dominated by tamarack (Larix laricina), 
and an area of calcareous groundwater seepage with sparsely vegetated 
marl precipitate (clay- or lime-rich soils that formed from solids that 
separated from water) at the surface (Michigan Natural Features 
Inventory 2012, p. 3). Shrubs and trees that may be present include 
shrubby cinquefoil (Potentilla fruticosa), bog birch (Betula pumila), 
and others (Michigan Natural Features Inventory 2012, p. 3).
    Based on the information above, we identify high-quality remnant 
(untilled) wet-mesic to dry tallgrass prairies, moist meadows, or 
prairie fen habitat, as described above, containing a high diversity of 
native plant species and sparse tree and shrub cover to be a physical 
or biological feature essential to the conservation of the Poweshiek 
skipperling. These native prairies should have no or low coverage of 
nonnative invasive plant species.
    Poweshiek skipperling are not known to disperse widely. The maximum 
dispersal distance for male Poweshiek skipperling travelling across 
contiguous suitable habitat is estimated to be approximately 1.6 km 
(1.0 mi) (Dana 2012a, pers. comm.). The species was evaluated among 291 
butterfly species in Canada and is thought to have relatively low 
mobility, lower mobility than that of the Dakota skipper (Burke et al. 
2011; Fitzsimmons 2012, pers. comm.). Therefore, a more conservative 
estimated dispersal distance would be that of the Dakota skipper, 
approximately 1 km (0.6 mi) (Cochrane and Delphey 2002, p. 6). 
Poweshiek skipperling frequently perch on vegetation, but males will 
occasionally patrol in search of mating opportunities (Royer and 
Marrone 1992b, p. 15). Poweshiek skipperling may move between patches 
of prairie habitat separated by structurally similar habitats (e.g., 
perennial grasslands but not necessarily native prairie); small 
populations need immigration corridors for dispersal from nearby 
populations to prevent genetic drift and to reestablish a population 
after local extirpation. The species will not likely disperse across 
unsuitable habitat, such as certain types of row crops, or anywhere not 
dominated by grasses (Westwood 2012, pers. comm.; Dana 2012a, pers. 
comm.).
    Poweshiek skipperling may move in response to local nectar sources, 
disturbance, or in search of a mate. The tallgrass prairie that once 
made up a vast ecosystem prior to European settlement has now been 
reduced to fragmented remnants that make up less than 1 to 15 percent 
of the original land area across the species' range (Samson and Knopf 
1994, p. 419). Before the range-wide fragmentation of prairie habitat, 
the species could move freely across suitable tallgrass prairie and 
between high-quality prairies through suitable dispersal habitat. Now, 
these fragmented populations need immigration corridors for dispersal 
from nearby populations to prevent genetic drift and perhaps to 
reestablish a population after local extirpation. Therefore, based on 
the information above, we identify undeveloped dispersal habitat, 
structurally similar to suitable high-quality prairie habitat, as 
described above, to be a physical or biological feature essential to 
the conservation of the Poweshiek skipperling. These dispersal habitats 
should be adjacent to or between high-quality prairie patches and 
within the known dispersal distance of Poweshiek skipperling; within 1 
km (0.6 mi) from

[[Page 63634]]

suitable high-quality tallgrass prairie or prairie fen and should have 
limited shrub and tree cover, and not consist of certain row crops 
(e.g., corn, beets), which may act as barriers to dispersal.
Food, Water, Air, Light, Minerals, or Other Nutritional or 
Physiological Requirements
    Preferred nectar plants vary across the geographic range of 
Poweshiek skipperling. Smooth ox-eye (Heliopsis helianthoides) and 
purple coneflower were noted as the preferred nectar plants in North 
Dakota, Iowa, and Minnesota (Swengel and Swengel 1999, p. 280, Selby 
2005, p. 5). In Wisconsin, other documented nectar species include 
stiff tickseed (Coreopsis palmata), black-eyed Susan, and palespike 
lobelia (Borkin 1995b, p. 6). On the relatively wet prairie habitats of 
Canada and prairie fens in Michigan, preferred nectar plants are black-
eyed Susan, palespike lobelia, sticky tofieldia (Triantha glutinosa), 
and shrubby cinquefoil (Dasiphora fruticosa ssp. floribunda) (Bess 
1988, p. 13; Catling and Lafontaine 1986, p. 65; Holzman 1972, p. 111; 
Nielsen 1970, p. 46; Summerville and Clampitt 1999, p. 231). Flowering 
forbs also provide water necessary to avoid desiccation during the 
flight period (Dana 2013, pers. comm.). Therefore, based on the 
information above, we identify the presence of native nectar plants, as 
listed above, that are flowering during the adult flight period of 
Poweshiek skipperling to be a physical or biological feature essential 
to the conservation of the Poweshiek skipperling.
    Poweshiek skipperling larvae may not rely on a single species of 
grass for food, but instead may be able to use a narrow range of 
acceptable plant species at a site (Dana 2005, pers. comm.). Dana 
(2005, pers. comm.) noted that larvae and ovipositing females prefer 
grasses with ``very fine, threadlike structures.'' Recent observations 
indicate that prairie dropseed is the preferred larval food plant for 
some Poweshiek skipperling populations (Borkin 1995b, pp. 5-6); larval 
feeding has also been observed on little bluestem (Borkin 1995b, pp. 5-
6) and sideoats grama (Bouteloua curtipendula) (Dana 2005, pers. 
comm.). Oviposition has been also observed on mat muhly (Cuthrell 2012, 
pers. comm.), a grass found in Michigan's prairie fens (Penskar and 
Higman 1999, p. 1). In general, to sustain all larval instars 
(developmental stages) and metamorphosis, Poweshiek skipperling require 
the availability of native, fine-stemmed grasses. Therefore, based on 
the information above, we identify native, fine-stemmed grasses, 
including but not limited to prairie dropseed, little bluestem, 
sideoats grama, and mat muhly to be a physical or biological feature 
essential to the conservation of the Poweshiek skipperling. These 
native grasses should be available during the larval stage of Poweshiek 
skipperling.
    Soil textures in areas that overlap with Poweshiek skipperling 
sites are classified as loam, sandy loam, or loamy sand (Royer et al. 
2008, pp. 3, 10); soils in moraine deposits are described as gravelly, 
but the deposits associated with glacial lakes are not described as 
gravelly. Michigan prairie fen habitat soils are described as saturated 
organic soils (sedge peat and wood peat) and marl, a calcium carbonate 
(CaCO3) precipitate (Michigan Natural Features Inventory Web 
site accessed August 3, 2012). The native-prairie grasses and flowering 
forbs detailed above are typically found on these types of soils (Royer 
et al. 2008, p. 4, Michigan Natural Features Inventory 2012, pp. 1-3). 
As discussed above, plant species community composition is generally 
higher in remnant prairies where the soils have never been plowed 
(Higgins et al. 2000, pp. 23-24) and certain native prairie plants are 
found only in prairies that lack a tillage history (Higgins et al. 
2000, p. 23). The physical state of cultivated soil can result in 
slower water movement, which can hamper root growth and seed 
germination (e.g., Tomko and Hall 1986, pp. 173-175). Therefore, we 
identify loam, sandy loam, loamy sand, gravel, organic peat or marl 
soils that have never been plowed or tilled to be a physical feature 
essential to the conservation of the Poweshiek skipperling.
Cover or Shelter
    Poweshiek skipperlings lay their eggs near native-grasses leaf-
blade tips (McAlpine 1972, pp. 85-93); McAlpine did not identify the 
grasses, but Dana (2005, pers. comm.) noted that larvae and ovipositing 
females prefer grasses with ``very fine, threadlike structures'' such 
as prairie dropseed (Borkin 1995b, pp. 5-6); little bluestem (Borkin 
1995b, pp. 5-6), sideoats grama (Bouteloua curtipendula) (Dana 2005, 
pers. comm.), and mat muhly (Cuthrell 2012, pers. comm.). After 
hatching, Poweshiek larvae crawl to the base of native grasses. Larvae 
emerge at night to forage, clip off blades of grass, and then crawl 
back to consume the grass (Dana 2012b, pers. comm.). Unlike Dakota 
skippers, Poweshiek skipperling do not burrow into the soil surface 
(McAlpine 1972, pp. 88-92, Borkin 1995b, p. 9). Therefore, sufficient 
availability of grasses used to form shelters at the ground surface is 
a physical or biological feature essential for cover and shelter for 
Poweshiek skipperling larvae.
    Similar to Dakota skipper, as discussed above, Poweshiek 
skipperling larvae are vulnerable to desiccation during hot, dry 
weather and may require wet low areas to provide relief from high 
summer temperatures or fire (Borkin 1994, p. 8, 1995a, p. 10). 
Poweshiek skipperling adults also require low wet areas to provide 
refugia from fire (Borkin 1994, p. 8, 1995a, p. 10). Therefore, based 
on the information above, we identify the presence of low wet areas 
that provide shelter and relief from high summer temperatures and fire 
for both larvae and adults, to be a physical or biological feature for 
the Poweshiek skipperling.
Sites for Breeding, Reproduction, or Rearing (or Development) of 
Offspring
    The annual, single generation of adult Poweshiek skipperling 
emerges from mid-June to early July, although the actual flight period 
varies somewhat across the species' range and can also vary 
significantly from year-to-year depending on weather patterns (Royer 
and Marrone 1992b, p. 15, Skadsen 1997, Swengel and Swengel 1999, p. 
282). The flight period in a locality lasts two to four weeks, and 
mating occurs throughout this period (McCabe and Post 1977a, p. 38, 
Swengel and Swengel 1999, p. 282). During this time, adult Poweshiek 
skipperling depend on nectar plants for food and water. Therefore, it 
is important that nectar plants are available in close proximity to 
areas suitable for oviposition and larval feeding. Adult male Poweshiek 
skipperling perch on tall grasses and forbs, and appear to patrol in 
search of mating opportunities (Royer and Marrone 1992b, p. 15). 
Therefore, the physical or biological features essential to the 
conservation of Poweshiek skipperling include above-ground parts of 
grasses and forbs for perching.
    As described above, Poweshiek skipperling lay their eggs near the 
tips of leaf blades (McAlpine 1972, pp. 85-93). Poweshiek skipperling 
larvae crawl to the base of grasses and emerge at night to forage, clip 
off blades of grass, and then crawl back down to consume the grass 
(Dana 2012b, pers. comm.). Therefore, the physical or biological 
features essential to the conservation of Poweshiek skipperling include 
above-ground parts of grasses for oviposition and larval foraging and 
shelter; these grasses should be in close proximity to nectar plants, 
where the adults are feeding during the short flight period.

[[Page 63635]]

    Poweshiek skipperling larvae are vulnerable to desiccation during 
hot, dry weather (Borkin 1994, p. 8, 1995a, p. 10). After hatching, 
Poweshiek larvae crawl to the base of grasses, but unlike Dakota 
skippers, Poweshiek skipperling do not form shelters underground, 
therefore, nonbiotic factors such as temperature and relative humidity 
at and near (to a 2.0 cm depth; 0.79 in) the soil surface may limit the 
survival of the sensitive larval and pupal stages of Poweshiek 
skipperling, as has been suggested for Dakota skippers (Royer et al. 
2008, p. 2). Soil evaporation rates in the north-central United States 
are substantially affected by microtopography (evenness of the soil 
surface on a small scale) (Cooper 1960 in Royer et al. 2008, p. 2). For 
example, removal of vegetation due to livestock grazing, plowing, fire, 
and soil compaction alters evaporation and water movement through the 
soil, thereby altering the humidity of soil near the surface (e.g., 
Tomko and Hall 1986, pp. 173-175; Zhao et al. 2010, pp. 93-96). 
Livestock grazing increases soil bulk density (an indicator of soil 
compaction) (Greenwood et al. 1997, p. -- Zhao et al. 2007, p. 248), 
and these increases have been correlated with decreased soil water 
content and movement of water through the soil (Zhao et al. 2007, p. 
248). The loss of porosity results in higher bulk densities, thereby 
decreasing water movement through the soil (Warren et al. 1986, pp. 
493-494). Furthermore, bulk density affects plant growth (Gardiner and 
Miller 2008, p. 36) and, therefore, can alter the plant community. For 
example, a rapid shift in plant community was documented in wet-mesic 
habitats in North Dakota that were grazed (McCabe 1979, p. 17, 1981, p. 
179). The shift in plant community due to intensive grazing composition 
may occur rapidly (McCabe 1981, p. 179; Royer and Royer 1998, p. 23). 
Similarly, tilled land increases bulk densities (e.g., Tomko and Hall 
1986, pp. 173-175). During the hot and dry summer months, these changes 
in the soil restrict the movement of shallow groundwater to the soil 
surface (Royer et al. 2008, p. 2), thus resulting in a dry soil layer 
during the summer months (Royer et al. 2008, p. 2), when Poweshiek 
skipperling larvae are vulnerable to desiccation (Borkin 1994, p. 8; 
Borkin 1995a, p. 10).
    Although Poweshiek skipperling habitats have not been studied 
extensively in terms of micro-climate, Royer (2008, pp. 4-5) studied 
six sites throughout the range of Dakota skipper that overlap with 
Poweshiek skipperling sites. The six sites represent Type B habitats, 
which are described as rolling native prairie terrain over gravelly 
glacial moraine deposits (Royer and Marrone 1992a, pp. 21-22). Royer 
(2008, pp. 7, 14-15) found the following acceptable levels for 
microclimatological (climate in a small space, such as at or near the 
soil surface) variables between the soil surface and 2.0 cm (0.79 in) 
deep throughout the range of Dakota skippers during the summer season 
(from when eggs are laid through when larvae enter diapause near the 
end of September): mean temperature range of 17.8 to 20.5 [deg]C (64.0 
to 68.9 [deg]F), mean dew point ranging from 13.9 to 16.8 [deg]C (57.0 
to 62.2 [deg]F), and mean relative humidity between 72.5 and 85.1 
percent. Bulk density at the six sites ranged from 0.86g/cm\3\ to 0.96 
g/cm\3\ (0.5 oz/in\3\; to 0.55 oz/in\3\); mean bulk density was below 
1.0 g/cm\3\ (0.8 oz/in\3\). Type B habitat are associated with gravelly 
glacial landscapes of predominantly sandy loams and loamy sand soils 
with relatively higher relief, more variable soil moisture, and 
slightly higher soil temperatures than Type A habitats (Royer et al. 
2008, p. 15). These variables have not been studied in Iowa, Michigan, 
and Wisconsin sites.
    Micro-climate conditions near the soil surface conducive to 
Poweshiek skipperling larvae survival are characteristic of untilled 
glacial soils without intense grazing pressure. Therefore, untilled 
glacial soils that are not subject to intense grazing pressure are 
physical or biological features essential to the conservation of the 
Poweshiek skipperling.
Habitats Protected From Disturbance or Representative of the 
Historical, Geographic, and Ecological Distributions of the Species
    The Poweshiek skipperling has a restricted geographic distribution. 
Species whose populations exhibit a high degree of isolation are 
extremely susceptible to extinction from both random and nonrandom 
catastrophic natural or human-caused events. Therefore, it is essential 
to maintain the native tallgrass prairies and prairie fens upon which 
the Poweshiek skipperling depends. This means protection from 
disturbance caused by exposure to land management actions (cattle 
grazing, fire management, destruction or conversion, early haying, and 
herbicide or pesticide use), flooding, water withdrawal or depletion, 
water contamination, lack of management, and nonnative species that may 
degrade the availability of native grasses and flowering forbs. The 
Poweshiek skipperling must, at a minimum, sustain its current 
distribution for the species to continue to persist. Introduced 
nonnative species are a serious threat to native tallgrass prairies and 
prairie fens on which Poweshiek skipperling depends ((Orwig 1997, pp. 
4, 8, MNFI unpubl. data 2011, Skadsen 2002, p. 52, Royer and Royer 
2012b, pp. 15-16, 22-23); see both Factor C: Disease and Predation, and 
Factor E: Other Natural or Manmade Factors Affecting Its Continued 
Existence sections of our proposed listing rule published elsewhere in 
today's Federal Register).
    Because the distribution of the Poweshiek skipperling is isolated 
and its habitat so restricted, introduction of certain nonnative 
species into its habitat could be devastating. Poweshiek skipperling 
typically occur at sites embedded in agricultural or developed 
landscapes, which makes them more susceptible to nonnative or woody 
plant invasion. Potentially harmful nonnative species include leafy 
spurge (Euphorbia esula), Kentucky bluegrass, alfalfa (Medicago 
sativa), glossy buckthorn (Frangula alnus), smooth brome, purple 
loosestrife (Lythrum salicaria), Canada thistle (Cirsium arvense), reed 
canary grass (Phalaris arundinacea), gray dogwood (Cornus racemosa), 
and others (Orwig 1997, p. 4, 8, MNFI unpubl. data 2011, Skadsen 2002, 
p. 52, Royer and Royer 2012b, pp. 15-16, 22-23). Once these plants 
invade a site, they replace or reduce the coverage of native forbs and 
grasses used by adults and larvae of both butterflies. Leafy spurge 
displaces native plant species and its invasion is facilitated by 
actions that remove native plant cover and expose mineral soil (Belcher 
and Wilson 1989, p. 172). The threat from nonnative invasive species is 
compounded by the encroachment of native woody species into native 
prairie habitat. Invasion of tallgrass prairie by woody vegetation such 
as glossy buckthorn reduces light availability, total plant cover, and 
the coverage of grasses and sedges (Fiedler and Landis 2012, pp. 44, 
50-51). This in turn reduces the availability of both nectar and larval 
host plants for Poweshiek skipperling.
    In Michigan, Poweshiek skipperling live on prairie fens, which 
occur on the lower slopes of glacial moraines or ice contact ridges 
(Albert 1995 in Michigan Natural Features Inventory 2012, p. 1) where 
coarse glacial deposits provide high hydraulic connectivity that forces 
groundwater to the surface (Moran 1981 in Michigan Natural Features 
Inventory 2012, p. 1). Small lakes, headwater streams, or rivers are 
often associated with prairie fens. The sapric peat (partially 
decomposed vegetation with less than one-third recognizable plant

[[Page 63636]]

fibers) substrate typical of prairie fens is saturated with calcareous 
(rich in calcium in magnesium bicarbonate) groundwater as a result of 
its filtration through glacial deposits. These bicarbonates often 
precipitate as marl at the soil surface. The typical pH ranges from 6.8 
to 8.2 (Michigan Natural Features Inventory 2012, p. 1). As described 
above, prairie fens may include some low shrubs and trees, but the 
amount of tree and shrub cover should not cause a barrier to dispersal 
(i.e., >15% trees or shrubs). Prior to European settlement, fires on 
upland habitats likely spread to adjacent prairie fens, which inhibited 
shrub invasion and maintained the open prairie fen plant community 
(Michigan Natural Features Inventory 2012, pp. 1-3). Now, the 
vegetation is largely a result of the unique hydrology; the plant 
community consists of obligate wetland and calcicolous species (species 
that thrive in lime-rich soils) mixed with tallgrass prairie and sedge 
meadow species (Michigan Natural Features Inventory 2012, pp. 1-3). The 
hydraulic processes connecting groundwater to the surface are essential 
to maintain the vegetative structure of prairie fens and are, 
therefore, a physical or biological feature essential to the 
conservation of the Poweshiek skipperling.
    Poweshiek skipperling are obligate residents of untilled high-
quality prairie, ranging from wet-mesic tallgrass prairie to dry-mesic 
mixed-grass prairie to prairie fens (Royer and Marrone 1992a, pp. 8, 
21). High-quality remnant tallgrass prairies and prairie fens contain a 
high diversity of native species, including flowering herbaceous 
species (forbs) (Dana 2001, pers. comm.). Degraded habitat consists of 
a high abundance of nonnative plants, woody vegetation, and a low 
abundance of native grasses and flowering forbs available during the 
larval growth period and a low abundance of native flowering forbs 
available during adult nectaring periods. Intense grazing or fire 
management practices, early haying, flooding, as well as lack of 
management create such degraded habitats. Conversion to agriculture or 
other development also degrades or destroys native prairie habitat. 
Therefore, based on the information above, we identify the necessary 
physical or biological features for the Poweshiek skipperling as 
nondegraded habitat devoid of nonnative plant species, or habitat in 
which nonnative plant species and nonnative woody vegetation are at 
levels that allow persistence of Poweshiek skipperling.

Summary

    We identify high-quality remnant untilled tallgrass prairies, moist 
meadows, or prairie fen habitat containing a high diversity of native 
plant species including a mosaic of native grasses and flowering forbs 
to be a physical or biological feature necessary for population growth 
and normal behavior of Poweshiek skipperling. These prairies have 
edaphic features that support the development and survival of larval 
Poweshiek skipperling and soil textures that are loam, sandy loam, 
loamy sand, gravel, or peat. Biological features that provide food 
sources for larvae are native fine-stemmed grass species, such as 
prairie dropseed, little bluestem, sideoats grama or mat muhly, and 
native forb plant species for adult nectar and water sources, such as 
purple coneflower, black-eyed Susan, stiff tickseed, palespike lobelia, 
sticky tofieldia, and shrubby cinquefoil. Physical or biological 
features for breeding, reproduction and offspring include grasses and 
forbs at or above the ground surface used for perching by adults and 
grasses at or above the ground surface used for oviposition as well as 
for larval shelter. Physical or biological features that provide cover 
or shelter dispersed within or adjacent to native prairies include 
areas for relief from high summer temperatures and fire, such as 
depressional wetlands, low wet areas, within or adjacent to prairies 
and edaphic features that are conducive to the development and survival 
of larval Poweshiek skipperling.
    These high-quality native tallgrass prairies and prairie fens have 
limited tree and low shrub coverage that may act as barriers to 
dispersal. These habitats also have limited or no invasive plant 
species that may lead to a change in the plant community. Physical or 
biological features that provide cover or shelter and relief from high 
summer temperatures include depressional wetlands, low wet areas, as 
well as undisturbed glacial soils. Contiguous prairie habitat that once 
characterized the historical distribution of the species has been 
severely fragmented; therefore, dispersal habitat, structurally similar 
to suitable high-quality prairie habitat and adjacent to or between 
high-quality prairie patches within the known dispersal distance of 
Poweshiek skipperling (within 1 km from suitable high-quality prairie 
or prairie fens) is another physical and biological feature identified 
for the Poweshiek skipperling to help maintain genetics and to provide 
refuges from disturbance. The unique hydrology that supports prairie 
fen vegetation is an essential physical and biological feature for 
Poweshiek skipperling in Michigan prairie fens.
Primary Constituent Elements
Dakota Skipper
    Under the Act and its implementing regulations, we are required to 
identify the physical or biological features essential to the 
conservation of Dakota skipper in areas occupied at the time of 
listing, focusing on the features' primary constituent elements. We 
consider primary constituent elements to be the elements of physical or 
biological features that provide for a species' life-history processes 
and are essential to the conservation of the species.
    Based on our current knowledge of the physical or biological 
features and habitat characteristics required to sustain the species' 
life-history processes, we determine that the primary constituent 
elements specific to the Dakota skipper are:
    (1) Primary Constituent Element 1--Wet-mesic tallgrass or mixed-
grass remnant untilled prairie that occurs on near-shore glacial lake 
soil deposits or high-quality dry-mesic remnant untilled prairie on 
rolling terrain consisting of gravelly glacial moraine soil deposits, 
containing:
    a. A predominance of native grasses and native flowering forbs,
    b. Glacial soils that provide the soil surface or near surface 
(between soil surface and 2 cm depth) micro-climate conditions 
conducive to Dakota skipper larval survival and native prairie 
vegetation such as, mean soil surface summer temperatures from 17.8 to 
20.5 [deg]C (64.0 to 68.9[emsp14][deg]F), mean near soil surface dew 
point ranging from 13.9 to 16.8 [deg]C (57.0 to 62.2[emsp14][deg]F), 
mean near soil surface relative humidity between 72.5 and 85.1 percent, 
and soil bulk densities between 0.86g/cm\3\ and 1.28 g/cm\3\ (0.5 oz/
in\3\ to 0.74 oz/in\3\);
    c. If present, trees or large shrub cover of less than 5 percent of 
area in dry prairies and less than 25 percent in wet-mesic prairies; 
and
    d. If present, nonnative invasive plant species occurring in less 
than 5 percent of area.
    (2) Primary Constituent Element 2--Native grasses and native 
flowering forbs for larval and adult food and shelter, specifically;
    a. At least one of the following native grasses to provide larval 
food and shelter sources during Dakota skipper larval stages: Prairie 
dropseed (Sporobolus heterolepis) or little bluestem (Schizachyrium 
scoparium); and
    b. One or more of the following forbs in bloom to provide nectar 
and water

[[Page 63637]]

sources during the Dakota skipper flight period: Purple coneflower 
(Echinacea angustifolia), bluebell bellflower (Campanula rotundifolia), 
white prairie clover (Dalea candida), upright prairie coneflower 
(Ratibida columnifera), fleabane (Erigeron spp.), blanketflower 
(Gaillardia spp.), black-eyed Susan (Rudbeckia hirta), yellow sundrops 
(Calylophus serrulatus), groundplum milkvetch (Astragalus 
crassicarpus), common gaillardia (Gaillardia aristata), or tooth-leaved 
primrose (Calylophus serrulata).
    (3) Primary Constituent Element 3--Dispersal grassland habitat that 
is within 1 km (0.6 mi) of native high-quality remnant prairie (as 
defined in Primary Constituent Element 1) that connects high-quality 
wet-mesic to dry tallgrass prairies or moist meadow habitats. Dispersal 
grassland habitat consists of undeveloped open areas dominated by 
perennial grassland with limited or no barriers to dispersal including 
tree or shrub cover less than 25 percent of the area and no row crops 
such as corn, beans, potatoes, or sunflowers.
    With this proposed designation of critical habitat, we intend to 
identify the physical or biological features essential to the 
conservation of the species, through the identification of the 
features' primary constituent elements sufficient to support the life-
history processes of the species.
    All units and subunits proposed to be designated as critical 
habitat that are currently occupied by the Dakota skipper contain the 
primary constituent elements sufficient to support the life-history 
needs of the species. Additional unoccupied units that we determine are 
essential for the conservation of the species also contain the primary 
constituent elements sufficient to support the life-history needs of 
the species.
Poweshiek Skipperling
    Under the Act and its implementing regulations, we are required to 
identify the physical or biological features essential to the 
conservation of Poweshiek skipperling in areas occupied at the time of 
listing, focusing on the features' primary constituent elements. We 
consider primary constituent elements to be the elements of physical or 
biological features that provide for a species' life-history processes 
and are essential to the conservation of the species.
    Based on our current knowledge of the physical or biological 
features and habitat characteristics required to sustain the species' 
life-history processes, we determine that the primary constituent 
elements specific to the Poweshiek skipperling are:
    (1) Primary Constituent Element 1--Wet-mesic to dry tallgrass 
remnant untilled prairies or remnant moist meadows containing:
    a. A predominance of native grasses and native flowering forbs;
    b. Undisturbed (untilled) glacial soil types including, but not 
limited to, loam, sandy loam, loamy sand, gravel, organic soils (peat), 
or marl that provide the edaphic features conducive to Poweshiek 
skipperling larval survival and native prairie vegetation;
    c. Depressional wetlands or low wet areas, within or adjacent to 
prairies that provide shelter from high summer temperatures and fire;
    d. If present, trees or large shrub cover less than 5 percent of 
area in dry prairies and less than 25 percent in wet-mesic prairies and 
prairie fens; and
    e. If present, nonnative invasive plant species occurring in less 
than 5 percent of area.
    (2) Primary Constituent Element 2--Prairie fen habitats containing:
    a. A predominance of native grasses and native flowering forbs;
    b. Undisturbed (untilled) glacial soil types including, but not 
limited to, organic soils (peat), or marl that provide the edaphic 
features conducive to Poweshiek skipperling larval survival and native 
prairie vegetation;
    c. Depressional wetlands or low wet areas, within or adjacent to 
prairies that provide shelter from high summer temperatures and fire;
    d. Hydraulic features necessary to maintain prairie fen groundwater 
flow and prairie fen plant communities;
    e. If present, trees or large shrub cover less than 25 percent of 
the unit; and
    f. If present, nonnative invasive plant species occurring in less 
than 5 percent of area.
    (3) Primary Constituent Element 3--Native grasses and native 
flowering forbs for larval and adult food and shelter, specifically;
    a. At least one of the following native grasses available to 
provide larval food and shelter sources during Poweshiek skipperling 
larval stages: prairie dropseed (Sporobolus heterolepis), little 
bluestem (Schizachyrium scoparium), sideoats grama (Bouteloua 
curtipendula), or mat muhly (Muhlenbergia richardsonis); and
    b. At least one of the following forbs in bloom to provide nectar 
and water sources during the Poweshiek skipperling flight period: 
purple coneflower (Echinacea angustifolia), black-eyed Susan (Rudbeckia 
hirta), smooth ox-eye (Heliopsis helianthoides), stiff tickseed 
(Coreopsis palmata), palespike lobelia (Lobelia spicata), sticky 
tofieldia (Triantha glutinosa), or shrubby cinquefoil (Dasiphora 
fruticosa ssp. floribunda).
    (4) Primary Constituent Element 4--Dispersal grassland habitat that 
is within 1 km (0.6 mi) of native high-quality remnant prairie (as 
defined in Primary Constituent Element 1) that connects high quality 
wet-mesic to dry tallgrass prairies, moist meadows, or prairie fen 
habitats. Dispersal grassland habitat consists of the following 
physical characteristics appropriate for supporting Poweshiek 
skipperling dispersal: undeveloped open areas dominated by perennial 
grassland with limited or no barriers to dispersal including tree or 
shrub cover less than 25 percent of the area and no row crops such as 
corn, beans, potatoes, or sunflowers.
    With this proposed designation of critical habitat, we intend to 
identify the physical or biological features essential to the 
conservation of the species, through the identification of the 
features' primary constituent elements sufficient to support the life-
history processes of the species. Many of the units proposed to be 
designated as critical habitat are currently occupied by the Poweshiek 
skipperling and contain the primary constituent elements sufficient to 
support the life-history needs of the species. Additional unoccupied 
units also contain the primary constituent elements sufficient to 
support the life-history needs of the species.

Special Management Considerations or Protection

    When designating critical habitat, we assess whether the specific 
areas within the geographical area occupied by the species at the time 
of listing contain features that are essential to the conservation of 
the species and which may require special management considerations or 
protection. All areas proposed for designation as critical habitat as 
described below may require some level of management to address the 
current and future threats to the physical or biological features 
essential to the conservation of Dakota skipper and Poweshiek 
skipperling. In all of the described units, special management may be 
required to ensure that the habitat is able to provide for the 
biological needs of both species.
    A detailed discussion of the current and future threats to Dakota 
skipper and Poweshiek skipperling can found in the proposed listing 
rule to list each species as an endangered species, which is published 
elsewhere in today's Federal Register. In general, the features

[[Page 63638]]

essential to the conservation of Dakota skipper and Poweshiek 
skipperling may require special management considerations or protection 
to reduce the following individual threats and their interactions:
    (1) The direct and indirect impacts of land use conversions, 
primarily from urban and energy development, gravel mining, and 
conversion to agriculture;
    (2) invasive species encroachment and secondary succession of woody 
plants;
    (3) grazing that reduces or continues to suppress the availability 
or predominance of native plants that provide larval food and adult 
nectar;
    (4) wetland destruction and degradation such that the affected area 
is flooded or drained of water permanently or over a long term such 
that it increases the risk of invasive species invasion, changes the 
prairie plant community, or eliminates wet areas used as relief from 
high temperatures and fire;
    (5) herbicide application; and
    (6) the stochastic effects of drought or floods.
    The greatest, overarching threat to Dakota skipper and Poweshiek 
skipperling are habitat curtailment, destruction, and fragmentation. 
The aforementioned activities will require special management 
consideration not only for the direct effects of the activities on the 
species and their habitat, but also for their indirect effects and how 
they are cumulatively and individually increasing habitat curtailment, 
destruction, and fragmentation.
    Based on our analysis of threats to Dakota skipper and Poweshiek 
skipperling, special management activities that could ameliorate these 
threats include, but are not limited to, habitat maintenance or 
restoration activities that occur at an intensity, duration, spatial 
arrangement or timing that is not detrimental to the species. These 
activities include, but are not limited to:
    (1) Prescribed fire,
    (2) late-season haying (after August 1),
    (3) brush or tree removal,
    (4) prescribed low-intensity rotational grazing,
    (5) invasive species control, and
    (6) habitat preservation.
    Management activities should be of the appropriate timing, 
intensity, and extent to be protective of Dakota skipper and Poweshiek 
skipperling during all life stages (e.g., pupae, larvae, and adults) 
and to maximize habitat quality and quantity. Some management 
activities, depending on how they are implemented, can have intensive 
impacts to the species, its habitat, or both. Depending on site-
specific conditions, management that includes prescribed fire and some 
low-intensity grazing must affect no more than one-quarter to one-third 
of the occupied habitat at a site in any single year to ensure that the 
resulting mortality or effects to reproduction do not have undue 
impacts on population viability. Management activities should protect 
the primary constituent elements for the species by conserving the 
extent of the habitat patches, the quality of habitat within the 
patches, and connectivity among occupied patches (e.g., see Schmitt, 
2003). Appropriate management helps increase the number of individuals 
reproducing each year by minimizing the activities that may harm Dakota 
skippers or Poweshiek skipperling during adult, larval, or pupal 
stages.
    Such special management activities may be required to protect the 
physical or biological features and support the conservation of Dakota 
skipper and Poweshiek skipperling by preventing or reducing the loss, 
degradation, and fragmentation of native prairie landscapes. 
Additionally, management of critical habitat lands can increase the 
amount of suitable habitat and enhance connectivity among Dakota 
skipper and Poweshiek skipperling populations through the restoration 
of areas that were previously composed of native tallgrass and mixed-
grass prairie communities. The limited extent of native tallgrass and 
mixed-grass prairie habitats, particularly the eastern portion of the 
Poweshiek skipperling range, emphasizes the need for additional habitat 
into which the Poweshiek skipperling could expand to survive and 
recover as well as to allow for adjustment to changes in habitat 
availability that may result from climate change.

Criteria Used To Identify Critical Habitat

    As required by section 4(b)(2) of the Act, we use the best 
scientific data available to designate critical habitat. We review 
available information pertaining to the habitat requirements of the 
species. In accordance with the Act and its implementing regulation at 
50 CFR 424.12(e), we consider whether designating additional areas--
outside those currently occupied at the time of listing--are necessary 
to ensure the conservation of the species. We are proposing to 
designate critical habitat in areas within the geographical area 
currently occupied by Dakota skipper and Poweshiek skipperling as 
described in detail below. We also are proposing to designate specific 
areas outside the geographical area occupied by the Dakota skipper and 
Poweshiek skipperling at the time of listing that were historically 
occupied, but where we are uncertain of the current occupancy, and 
areas that are presently unoccupied, because such areas are essential 
for the conservation of the species.

Species Occupancy

    We generally considered a species to be ``present'' at sites where 
it was detected during the most recent survey, if the survey was 
conducted in 2002 or more recently and no evidence suggests that the 
species is now extirpated from the site, (e.g., no destruction or 
obvious and significant degradation of the species' habitat), with the 
exception of one Poweshiek skipperling site and four Dakota skipper 
sites, which are discussed in detail in the listing rule published 
elsewhere in this Federal Register. At these five sites, there is no 
evidence to suggest the species is not still present because the 
habitat and management is still considered to be conducive to the 
species, the occupancy status was supported by the species expert 
review of the site, and at least one of these sites had a 2012 habitat 
assessment that concluded that the habitat was suitable for the 
species.
    We assigned a status of ``unknown'' if the species was found in 
1993 or more recently, but not in the most recent one to two sequential 
survey year(s) since 1993 and we found no evidence to suggest the 
species is now extirpated from the site (e.g., no destruction or 
obvious and significant degradation of the species' habitat). We 
considered a species to be ``possibly extirpated'' at sites where it 
was detected at least once prior to 1993, but not in the most recent 
one to two sequential survey years(s). A species is also considered 
``possibly extirpated'' at sites where it was found prior to 1993 and 
no surveys have been conducted in 1993 or more recently. At least three 
sequential years of negative surveys were necessary for us to consider 
the species ``extirpated'' from a site, because of the difficulty of 
detecting these species, as explained further in this section. A 
species is also considered ``extirpated'' at sites where habitat for 
the species is no longer present.
    When determining whether the species occupancy is unknown, possibly 
extirpated, or extirpated at a particular site, we used the survey year 
1993 as a cut-off date, because most known sites (more than 75 percent 
of known Poweshiek skipperling sites and more than 89 percent of known 
Dakota

[[Page 63639]]

skipper sites) have been surveyed at least once since 1993 and survey 
data more than 20 years old may not reflect the current status of a 
species or its habitat at a site (for example, due to habitat loss from 
secondary succession of woody vegetation or a change in plant 
communities due to invasive species). Although it cannot be presumed 
that the species is absent at sites not surveyed since 1993, the 
likelihood of occupancy of these sites should be considered differently 
than sites with more recent survey data (e.g., due to woody vegetation 
succession over time). When analyzing survey results, we disregarded 
negative surveys conducted outside of the species' flight period or 
under unsuitable conditions (e.g., high wind speeds).
    After we applied these standards to initially ascertain the status 
of the species, we asked species experts and Service personnel to help 
verify, modify, or correct species' occupancy at each site 
(particularly for sites with questionable habitat quality or those that 
have not been surveyed recently). In most cases, we used the status 
confirmed during expert review, unless we received additional 
information (e.g., additional survey or habitat data provided after the 
expert reviews) that suggests a different status at a particular site.
    Timing of surveys is based on initial field checks of nectar plant 
blooms and sightings of butterfly species with synchronous emergence 
(sightings of butterfly species that emerge at the same time as Dakota 
skipper and Poweshiek skipperling), and, more recently, emergence 
estimated by a degree-day emergence model using high and low daily 
temperature data from weather stations near the survey sites (Selby, 
undated, unpublished dissertation). Surveys are conducted during flight 
periods when the species' abundance is expected to be at levels at 
which the species can be detected. However, as with many rare species, 
detection probabilities are imperfect and some uncertainty remains 
between non-detection and true absence (Gross et al. 2007, pp. 192, 
197-198; Pellet 2008, pp. 155-156). Three sequential years of negative 
surveys is sufficient to capture variable detection probabilities, 
since each survey year typically encompasses more than one visit (e.g., 
the average number of visits per Dakota skipper site per year ranges 
from 1 to 11) and the probability of false absence after 5-6 visits 
drops below 5 percent for studied butterfly species with varying 
average detection probabilities (Pellet 2008, p. 159). Therefore, the 
site is considered ``extirpated'' if there are three sequential years 
of negative surveys.
    It cannot be presumed that the species is not persisting at a site 
only because there have not been recent surveys. At several sites, the 
species has persisted for longer than 20 years; for example, Dakota 
skipper was first recorded at Scarlet Fawn Prairie in South Dakota in 
1985 and has had positive detections every survey since that date-the 
most recent detection was in 2012. The year 1993 was chosen based on 
habitat-related inferences, specifically, the estimated time for 
prairie habitat to degrade to non-habitat due to woody encroachment and 
invasive species. For example, native prairies with previous light-
grazing management that were subsequently left idle transitioned from 
mixed grass to a mix of woody vegetation and mixed grass in 13 years 
and it was predicted that these idle prairies would be completely lost 
due to woody succession in a 30-year timeframe (Penfound 1964, pp. 260-
261). The time for succession of idle prairie depends on numerous 
factors, such as the size of the site, edge effects (the changes that 
occur on the boundary of two habitat types), and the plant composition 
of adjacent areas.
    This approach is the most objective way to evaluate the data range-
wide. Most sites have been surveyed over multiple years, although the 
frequency and type of surveys varied among sites and years. In several 
cases, species experts provided input on occupancy based on their 
familiarity with the habitat quality and stressors to populations at 
particular sites.
    We determined current occupancy using occurrence data from the 
Service's Dakota skipper geodatabase (Service 2013, unpubl, 
geodatabase) and Poweshiek skipperling database (Service 2013, unpubl. 
data), which were built based on survey reports from throughout the 
range of the species and expert input. Areas with occurrence records or 
sites classified as ``present'' (see Background of the proposed listing 
rule and above for definitions) are considered occupied, while areas 
where the species is presumed extirpated or possibly extirpated are 
considered currently unoccupied, but occupied historically.
    Several proposed critical habitat units contain several nearby 
survey sites (or point occurrences) that occur within the maximum 
estimated dispersal distance of Dakota skipper and Poweshiek 
skipperling. Because the species could move between these sites (or 
occurrences), if several sites are contained within one CH unit, we 
used the ``best'' status for the species to determine occupancy in 
areas where the habitat was contiguous. For example, if there are two 
sites (or occurrences) within a proposed critical habitat unit and one 
site has a status of present and the other status is unknown, we used 
the status of present and considered the unit to be occupied. We did 
this because we found it reasonable to assume that the species could 
travel between sites (or point occurrence locations) if they were 
within the maximum dispersal distance of each other and if we 
determined that the habitat between point locations was, at the 
minimum, suitable for dispersal. Furthermore, the delineation of what 
constituted a ``site'' by surveyors was often not ecologically based, 
but was instead based on ownership or political boundaries and may only 
roughly approximate the extent of a suitable habitat patch.
    The status of the species is unknown at a number of sites--in other 
words, we are not certain whether the species may be extant at 
densities that are so low that it has not been recently detected, or if 
it is truly absent at these sites. Therefore, we are uncertain of the 
occupancy in units where the best species status is unknown. Areas with 
an uncertain occupancy were examined to determine if such areas were 
essential for the conservation of the species. In other words, for the 
purposes of these critical habitat designations, we are considering 
these areas to be unoccupied at the time of listing and we examined 
these areas with uncertain occupancy using the same criteria as we used 
for unoccupied areas. We also examined lands where the status of the 
species is considered to be possibly extirpated or extirpated to 
determine if such areas are essential for the conservation of the 
species.

Areas Occupied at Time of Listing

    We reviewed available information that pertains to the ecology, 
natural history, and habitat requirements of each species and evaluated 
all known species locations using data from the following sources: 
Spatial data for known species locations from the Minnesota Natural 
Heritage Program (MN DNR, 2012, entire data set), Michigan Natural 
Heritage Program (MI DNR 2011, entire data set), Michigan Natural 
Features Inventory (MNFI), regional Geographic Information System (GIS) 
coverages, recent biological surveys and reports; site visits and site-
specific habitat evaluations; research published in peer-reviewed 
articles and presented in academic theses or reports; and discussions 
with species experts.
    Criteria for selecting critical habitat units are based on species 
survey data

[[Page 63640]]

and the extent and distribution of essential habitat features. Our 
criteria are based on the available scientific information on habitat 
and distribution of the species (see ``Background'' section of the 
proposed listing rule). The criteria for selecting the occupied sites 
are: (1) Type, amount, and quality of habitat associated with occupied 
areas; (2) presence of the physical or biological features essential 
for the species; and (3) estimated population viability of the species 
in a particular area, if known.
    We considered occupied areas containing plant communities 
classified as (or based on the best available information and recent 
aerial photography) dry prairie, dry-mesic prairie, mesic prairie, or 
wet-mesic remnant (untilled) prairie as potential suitable habitat for 
Dakota skipper and Poweshiek skipperling. Prairie fens, as defined by 
the MNFI, were also considered as potential suitable habitat for 
Poweshiek skipperling in Michigan. Using state natural heritage 
rankings, habitat information from recent reports, and expert 
knowledge, we selected areas with habitat quality ratings of fair to 
excellent because these areas are most likely to contain the physical 
or biological features essential for the conservation of the species. 
In some cases the habitat was not given a quality rating, but instead 
the site was given an estimated population viability rating, in recent 
reports or heritage databases, which directly reflect the quality of 
the habitat (e.g., excellent population viability rating indicates the 
presence of high-quality native prairie habitat). Therefore, we 
selected sites with viability ranks of fair to excellent from the most 
recent reports available because these areas are most likely to contain 
the physical or biological features essential for the conservation of 
the species. Another physical or biological feature essential for the 
conservation of the species is grassland-dominated areas that are 
necessary for dispersal between higher quality prairies. Therefore, we 
also considered including areas that contain potential dispersal 
habitat to connect patches of higher quality native prairies that are 
(1) lesser quality (or unrated) native dry-mesic prairie, mesic 
prairie, or wet-mesic remnant prairies or other habitat types such as 
wet meadow, oak savannas, and other types of grassland-dominated areas 
(e.g., not row crops or dense forests) suitable for dispersal and (2) 
within 1 km (0.6 mi) of higher (fair to excellent) quality native 
prairie. In other words, more than one site may be contained in a 
single unit if the habitats are connected by areas that contain the 
physical or biological features essential for the conservation of the 
species (nearby sites may have been named as different sites, for 
example, in survey reports, due to changes in landownership, dispersal 
barriers that may have existed at the time of the survey, or other 
situations).

Why Occupied Areas Are Not Sufficient for the Conservation of Dakota 
Skippers and Why Unoccupied Areas Are Essential for the Conservation of 
the Species

    The Dakota skipper has experienced recent declines in large parts 
of its historical range. The species is now considered to be present at 
46 sites in the United States, including 14 sites in Minnesota, 18 
sites in North Dakota, and 14 sites in South Dakota. More than one site 
can be contained in a single proposed critical habitat unit; 
consequently, we are proposing a total of 31 occupied units (i.e., 6 
occupied units in Minnesota, 10 occupied units in North Dakota, and 10 
occupied units in South Dakota). The remaining sites where the species 
is considered to be present are located in Canada (45 of total 91), 
mostly within three isolated complexes, and were observed in either 
2002 or 2007 with no subsequent surveys.
    The areas of unoccupied habitat that we are proposing as critical 
habitat were recently occupied (had positive records in 1993 or more 
recently) and are within the historical range of the species. The areas 
of habitat where we are uncertain of the occupancy that we are 
proposing as critical habitat were recently occupied (generally, a site 
with an unknown occupancy had positive records in 1993 or more recently 
but may have had one or two years of negative surveys or were 
determined by a species expert in the state to have an unknown 
occupancy), and are within the historical range of the species. We 
determine that these unoccupied areas are essential for the Dakota 
skipper's conservation because the range of the species has been 
severely curtailed, occupied habitats are limited and isolated, 
population sizes are small, and additional lands will be necessary to 
recover the species.
    Furthermore, the unoccupied units and units where we are uncertain 
of the occupancy are needed to satisfy the conservation principles of 
redundancy, resiliency, and representation for the Dakota skipper, as 
there may be too few occupied areas remaining to ensure conservation of 
the species--the species having been extirpated from substantial 
portions of its range. The inclusion of unoccupied habitat and habitat 
where we are uncertain of the occupancy as proposed critical habitat is 
essential for the species' conservation in three ways: (1) It would 
substantially increase the diversity of historically occupied habitats 
and geographic areas to increase the chances of the species persisting 
despite demographic and environmental stressors that are not uniformly 
distributed; (2) it would ensure that at least some populations may be 
sufficiently large to withstand stochastic events; and, (3) it would 
help to ensure that geographic areas of recent importance to the 
species contain sufficient numbers of populations to maintain the 
species.
    Specifically, we are proposing unoccupied critical habitat units 
and units with uncertain occupancy to conserve habitat that may hold 
potential genetic representation of the species that is necessary for 
the species to conserve its adaptive capabilities across portions of 
its highly fragmented historical ranges. A 2002 study of Dakota skipper 
genetics showed that each Dakota skipper population studied had 
evidence of inbreeding and was subject to genetic drift that may erode 
its genetic variability over time (Britten and Glasford 2002, pp. 371-
372). Therefore, it is essential to conserve the range-wide genetic 
diversity we have for the species (and the habitats that may contain 
that diversity) to help safeguard the genetic representation necessary 
for the species to maintain its adaptive capabilities. The 
fragmentation of Dakota skipper's genetic diversity and limited 
detectability during low population densities further argue for the 
conservation value of populations currently defined as unknown. We are 
certain of the species' presence at relatively few sites and there 
remains some likelihood of Dakota skipper presence at sites where they 
have not been detected during recent surveys. In light of the species' 
fragmentation and the need to preserve any remaining genetic diversity, 
we believe it is also essential to conserve Dakota skipper at units 
where the occupancy of the species is unknown.
    Since a species' genetics is shaped by its environment, successful 
conservation should aim to preserve a species across the array of 
environments in which it occurs (Shaffer and Stein 2000, p. 308), 
especially if much remains unknown about the nature and extent of its 
genetic diversity. Conservation of habitat and genetic material is 
vital in the core of the species' range, but it is also critical to 
preserve the species in less typical habitats on the periphery of its 
range, for example, wet-mesic prairies in North

[[Page 63641]]

Dakota, to preserve the adaptive capabilities of the species over the 
long term.
    Genetic variation allows populations to tolerate a range of 
environmental stressors such as new infectious diseases, parasites, 
pollution, food sources, predators, and changes in climate. 
Fragmentation of a species' habitat across its range can ``exacerbate 
genetic drift and random fluctuations in allele frequencies, causing 
the genetic variation originally present within a large population to 
become redistributed among the remaining subpopulations'' (Redford et 
al. 2011, p. 41). Furthermore, a ``fully representative sample of 
founders is required, if the population is to encompass the genetic 
diversity in the wild and minimize subsequent inbreeding'' (Frankham et 
al. 2009, p. 434). Because there is evidence of range-wide genetic 
isolation and inbreeding, the Dakota skipper's historical genetic 
variation may be fragmented unevenly among the remaining 
subpopulations. As a basis of future reintroductions, a sample of 
founders representative of appropriate types and levels of genetic 
diversity (e.g., to minimize inbreeding) is essential to conserve the 
genetic material at units where we are uncertain of the occupancy.
    We are also proposing critical habitat units with uncertain 
occupancy and unoccupied units to help capture the habitats necessary 
for population persistence despite stochastic events--in other words, 
we would increase the likelihood that units would contain large enough 
populations to be resilient to those stressors. We do not know the 
minimum population size needed to attain an acceptable likelihood of 
population persistence of Dakota skipper, but we make inferences using 
data from populations for which we have some evidence of persistence--
in general, the chances of maintaining a species is thought to increase 
with the size of the sites. Insects may need a population size of more 
than 10,000 individuals to maintain population viability for 40 
generations (Trail et al. 2007 in Frankham et al. 2009, pp. 518-519). 
By increasing the resiliency of each unit (e.g., by ensuring an 
appropriate size), we are hoping to increase the chance of species 
persistence in individual units. In systematic surveys on Minnesota 
prairies, Swengel and Swengel (1997; 1999) found no Dakota skippers on 
the smallest remnants (< 20 ha (49 ac)), and significantly lower 
abundance on intermediate size (30-130 ha (74-321 ac)) than on larger 
tracts (>140 ha (346 ac)). We did not specify a minimum size for 
proposed critical habitat units; however, almost all of the proposed 
Dakota skipper critical habitat units are larger than 30 ha (74 ac) and 
are, therefore, more resilient to stochastic events. In general, 
researchers have made consistent observations of relatively small 
proposed critical habitat units that demonstrate persistence of the 
species or are one of a few units representative of a specific eco-
region or eco-region subsection (see the redundancy discussion below in 
this section), or a combination of these factors.
    Furthermore, the importance of conserving habitats with uncertain 
occupancy and unoccupied areas is vital in proposed units that contain 
sites that were, until recently, considered some of the best 
populations of the species range-wide. For example, some of the areas 
where we are uncertain of the species occupancy have had positive 
detections as recently as 2009. Other unoccupied units also had 
relatively recent detections; for example, one unoccupied unit in South 
Dakota had positive detections of the species in 2008, but the species 
is now extirpated at the site. In addition, some of these areas were 
considered to have, until recently, some of the best populations of 
Dakota skipper, but the populations have apparently suddenly 
disappeared or have been reduced to undetectable numbers, not due to 
habitat degradation or destruction, but instead due to unknown 
stressors (see further discussion in Factor E of the proposed listing 
rule published elsewhere in this Federal Register). These unoccupied 
units and units with uncertain occupancy are essential for the 
conservation of the Dakota skipper, particularly for future 
reintroduction efforts to aid species recovery, because they contain 
the habitat that is conducive to the species.
    Finally, by proposing unoccupied units and units where we are 
uncertain of the occupancy, we include areas that help to provide 
adequate redundancy within the Dakota skipperling's recent geographic 
distributions and full variety of habitat types. By including 
unoccupied units and units with uncertain occupancy, we will help to 
ensure that geographic areas of recent importance to the species 
contain sufficient numbers of populations to maintain the species. In 
order to conserve the Dakota skipper across the array of environments 
in which it occurs, we capture habitat redundancy by including a number 
of sites within each Bailey's eco-region (i.e., Bailey 1983, entire) 
section and subsection of critical habitat units that is roughly 
proportional to the number of sites with recent records within those 
areas. The Dakota skipper historically ranged across at least 10 eco-
region sections and 18 eco-region subsections, with the majority of 
historically documented sites from the Red River Valley, North Central 
Glaciated Plains, and North East Glaciated Plains eco-region sections 
(Service 2013, unpubl. geodatabase; Service 2013, unpubl.). Occupied 
units occur on 9 eco-region subsections within 5 eco-regions, the Red 
River Valley, North Central Glaciated Plains, North West Great Plains 
sections, and two sections with the same name (North East Glaciated 
Plains). By including unoccupied units and units with uncertain 
occupancy, we are capturing areas in 3 additional eco-region 
subsections within 2 sections (i.e., Lake Agassiz-Aspen Parklands and 
North East Glaciated Plains eco-region sections). Furthermore, by 
including unoccupied units and units with uncertain occupancy, we are 
including more areas within the eco-regions where a larger number of 
sites are located (e.g., Red River Valley, North Central Glaciated 
Plains, and North East Glaciated Plains eco-region sections); 
therefore, the number of units within each section and subsection is 
roughly proportional to the number of sites with recent records within 
those areas. These unoccupied units and units with uncertain occupancy 
are essential for the conservation of the Dakota skipper, particularly 
for future reintroduction efforts to aid species recovery, because they 
contain the habitat that is conducive to the species and help capture 
the environmental variability across the range of the species.
    In summary, representation, resiliency, and redundancy are the 
three conservation principles important to threatened and endangered 
species recovery (Shaffer and Stein 2000, p. 307) (USFWS 2004, p 89). 
Representation involves conserving the breadth of the genetic makeup of 
the species to conserve its adaptive capabilities; resiliency involves 
ensuring that each population is sufficiently large to withstand 
stochastic events; and redundancy involves ensuring a sufficient number 
of populations to provide a margin of safety for the species to 
withstand catastrophic events (USFWS 2004, p. 89). Both the occupied 
and unoccupied units are needed to satisfy the conservation principles 
of redundancy, resiliency, and representation for the Dakota skipper 
because there may be too few occupied areas remaining to ensure the 
species' conservation. The concepts

[[Page 63642]]

of representation, resiliency, and redundancy are not mutually 
exclusive; populations that contribute to the resiliency of a species 
may also contribute to its redundancy or representation. Furthermore, 
it may not be necessary for a single population to contribute to all 
three conservation principles to be important for maintaining the 
species across its range in the long term--because the Dakota skipper 
is being evaluated across its range, a particular population may not 
meet the strictest test of one of the three conservation principles yet 
contribute to the others.

Why Occupied Areas Are Not Sufficient for the Conservation of the 
Poweshiek Skipperling and Why Unoccupied Areas Are Essential for the 
Conservation of the Species

    The Poweshiek skipperling has experienced recent declines in large 
parts of its historical range. The species is now considered to be 
present at 10 sites in Michigan, 3 sites in Wisconsin, and 1 site in 
Manitoba. More than 1 site can be contained in a single proposed 
critical habitat unit; consequently, we are proposing a total of 10 
occupied units (i.e., 8 occupied units in Michigan and 2 occupied units 
in Wisconsin). Until relatively recently, Poweshiek skipperling was 
also present in native prairies in Iowa, Minnesota, North Dakota and 
South Dakota--none of these areas are included in occupied areas.
    The areas of unoccupied habitat that we are proposing as critical 
habitat were recently occupied (had positive records in 1993 or more 
recently) and are within the historical range of the species. The areas 
of habitat where we are uncertain of the occupancy that we are 
proposing as critical habitat were recently occupied (generally, a site 
with an unknown occupancy had positive records in 1993 or more recently 
but may have had one or two years of negative surveys or were 
determined by a species expert in the state to have an unknown 
occupancy), and are within the historical range of the species. We 
determine that these unoccupied areas are essential for the Poweshiek 
skipperling's conservation because the range of the species has been 
severely curtailed, occupied habitats are limited and isolated, 
population sizes are small, and additional lands will be necessary to 
recover the species.
    Furthermore, the unoccupied units and units where we are uncertain 
of the occupancy are needed to satisfy the conservation principles of 
redundancy, resiliency, and representation for the Poweshiek 
skipperling, as there may be too few occupied areas remaining to ensure 
conservation of the species--the species having been extirpated from 
substantial portions of its range. The inclusion of unoccupied habitat 
and habitat where we are uncertain of the occupancy as proposed 
critical habitat is essential for the species' conservation in three 
ways: (1) It would substantially increase the diversity of historically 
occupied habitats and geographic areas to increase the chances of the 
species persisting despite demographic and environmental stressors that 
are not uniformly distributed; (2) it would ensure that at least some 
populations may be sufficiently large to withstand stochastic events; 
and (3) it would help to ensure that geographic areas of recent 
importance to the species contain sufficient numbers of populations to 
maintain the species.
    Specifically, we are proposing unoccupied critical habitat units 
and units with uncertain occupancy to conserve habitat that may hold 
potential genetic representation of the species that is necessary for 
the species to conserve its adaptive capabilities across portions of 
its highly fragmented historical ranges. Poweshiek skipperling 
populations are small and fragmented, and thus are subject to genetic 
drift and inbreeding (Frankham et al. 2009, p. 309). Therefore, it is 
essential to conserve the range-wide genetic diversity we have for the 
species (and the habitats that may contain that diversity) to help 
safeguard the genetic representation necessary for the species to 
maintain its adaptive capabilities. The fragmentation of Poweshiek 
skipperling's genetic diversity and limited detectability during low 
population densities further argue for the conservation value of 
populations currently defined as unknown. We are certain of the 
species' presence at relatively few sites and there remains some 
likelihood of Poweshiek skipperling presence at sites where they have 
not been detected during recent surveys. In light of the species' 
fragmentation and the need to preserve any remaining genetic diversity, 
we believe it is also essential to conserve Poweshiek skipperling at 
units where the occupancy of the species is unknown.
    Since a species' genetics is shaped by its environment, successful 
conservation should aim to preserve a species across the array of 
environments in which it occurs (Shaffer and Stein 2000, p. 308), 
especially if much remains unknown about the nature and extent of its 
genetic diversity. Conservation of habitat and genetic material is 
vital in the core of the species' range, but it is also critical to 
preserve the species in less typical habitats on the periphery of its 
range, for example, prairie fens in Michigan, to preserve the adaptive 
capabilities of the species over the long term.
    Genetic variation allows populations to tolerate a range of 
environmental stressors such as new infectious diseases, parasites, 
pollution, food sources, predators, and changes in climate. 
Fragmentation of a species' habitat across its range can ``exacerbate 
genetic drift and random fluctuations in allele frequencies, causing 
the genetic variation originally present within a large population to 
become redistributed among the remaining subpopulations'' (Redford et 
al. 2011, p. 41). Furthermore, a ``fully representative sample of 
founders is required, if the population is to encompass the genetic 
diversity in the wild and minimize subsequent inbreeding'' (Frankham et 
al. 2009, p. 434). Because there is evidence of range-wide genetic 
isolation and inbreeding, the species' historical genetic variation may 
be fragmented unevenly among the remaining subpopulations. As a basis 
of future reintroductions, a sample of founders representative of 
appropriate types and levels of genetic diversity (e.g., to minimize 
inbreeding) is essential to conserve the genetic material at units 
where we are uncertain of the occupancy.
    We are also proposing critical habitat units with uncertain 
occupancy and unoccupied units to help capture the habitats necessary 
for population persistence despite stochastic events--in other words, 
we would increase the likelihood that units would contain large enough 
populations to be resilient to those stressors. We do not know the 
minimum population size needed to attain an acceptable likelihood of 
population persistence for either species, but we make inferences using 
data from populations for which we have some evidence of persistence--
in general, the chances of maintaining a species is thought to increase 
with the size of the sites. Insects may need a population size of more 
than 10,000 individuals to maintain population viability for 40 
generations (Trail et al. 2007 in Frankham et al. 2009, pp. 518-519). 
By increasing the resiliency of each unit (e.g., by ensuring an 
appropriate size), we are hoping to increase the chance of species 
persistence in individual units. Based on ten years of surveys in Iowa, 
Minnesota, and North Dakota, Poweshiek skipperling was found to peak in 
numbers in ``undegraded (never tilled)'' upland prairie sites that were

[[Page 63643]]

greater than 30 ha (74 ac) with some topographic diversity (referenced 
within Swengel and Swengel 2012, p. 3). Systematic surveys on Minnesota 
prairies show that Dakota skipper abundances increased with increasing 
size of sites (Swengel and Swengel 1999, pp. 278, 284). We did not 
specify a minimum size for proposed critical habitat units; however, 
almost all of the proposed Poweshiek skipperling critical habitat units 
in Minnesota, Iowa, South Dakota, North Dakota, and Wisconsin are much 
larger than 30 ha (74 ac) and are, therefore, more resilient to 
stochastic events. In general, relatively small proposed critical 
habitat units have had consistent observations that demonstrate 
persistence of the species or are one of a few units representative of 
a specific eco-region or eco-region subsection (see the redundancy 
discussion below in this section), or a combination of these factors.
    Furthermore, the importance of conserving habitats with uncertain 
occupancy and unoccupied units is vital in proposed units that contain 
sites that were, until recently, considered some of the best 
populations of the species range-wide. For example, some of the areas 
where we are uncertain of the species occupancy have had positive 
detections as recently as 2007. Other unoccupied units also had 
relatively recent detections, for example, as one unoccupied unit in 
Iowa and two unoccupied units in South Dakota contain sites that had 
positive detections of the species in 2008, but where the species is 
now extirpated. In addition, some of these areas were considered to 
have, until recently, some of the best populations of Poweshiek 
skipperlings, but the populations have apparently suddenly disappeared 
or have been reduced to undetectable numbers, not due to habitat 
degradation or destruction, but instead due to unknown stressors (see 
further discussion in Factor E of the proposed listing rule published 
in this Federal Register). These unoccupied units and units with 
uncertain occupancy are essential for the conservation of the Poweshiek 
skipperling, particularly for future reintroduction efforts to aid 
species recovery, because they contain the habitat that is conducive to 
the species.
    Finally, by proposing unoccupied units and units where we are 
uncertain of the occupancy, we include areas that help to provide 
adequate redundancy within the Poweshiek skipperling's recent 
geographic distributions and full variety of habitat types. By 
including unoccupied units and units with uncertain occupancy, we will 
help to ensure that geographic areas of recent importance to the 
species contain sufficient numbers of populations to maintain the 
species. In order to conserve the Poweshiek skipperling across the 
array of environments in which it occurs, we capture habitat redundancy 
by including a number of sites within each Bailey's eco-region (Bailey 
1983) section and subsection critical habitat units that is roughly 
proportional to the number of sites with recent records within those 
areas. The Poweshiek skipperling historically ranged across at least 12 
eco-regions sections and 21 eco-region subsections, with the majority 
of historically documented sites from the Red River Valley and North 
Central Glaciated Plains eco-region sections (Service 2013, unpubl. 
geodatabase; Service 2013, unpubl.). Occupied units occur on 3 eco-
region subsections within 2 eco-regions, the Jackson Interlobate 
Moraine and the Southwest Great Lakes Morainal sections. By including 
unoccupied units and units with uncertain occupancy, we are capturing 6 
additional eco-region subsections within 3 sections (i.e., Red River 
Valley, North Central Glaciated Plains, and the Minnesota and Northwest 
Iowa Morainal-Oak Savannah eco-region sections) roughly proportional to 
the number of sites with recent records within those areas. These 
additional eco-region subsections include core areas of the species 
range. These unoccupied units and units with uncertain occupancy are 
essential for the conservation of the Poweshiek skipperling, 
particularly for future reintroduction efforts to aid species recovery, 
because they contain the habitat that is conducive to the species and 
help capture the environmental variability across the range of the 
species.
    In summary, representation, resiliency, and redundancy are the 
three conservation principles important to threatened and endangered 
species recovery (Shaffer and Stein 2000, p. 307) (USFWS 2004, p 89). 
Representation involves conserving the breadth of the genetic makeup of 
the species to conserve its adaptive capabilities; resiliency involves 
ensuring that each population is sufficiently large to withstand 
stochastic events; and redundancy involves ensuring a sufficient number 
of populations to provide a margin of safety for the species to 
withstand catastrophic events (USFWS 2004, p. 89). Both the occupied 
and unoccupied units are needed to satisfy the conservation principles 
of redundancy, resiliency, and representation for the Poweshiek 
skipperling because there may be too few occupied areas remaining to 
ensure the species' conservation. The concepts of representation, 
resiliency, and redundancy are not mutually exclusive; populations that 
contribute to the resiliency of a species may also contribute to its 
redundancy or representation. Furthermore, it may not be necessary for 
a single population to contribute to all three conservation principles 
to be important for maintaining the species across its range in the 
long term--because the Poweshiek skipperling is being evaluated across 
its range, a particular population may not meet the strictest test of 
one of the three conservation principles yet contribute to the others.

Areas Unoccupied at Time of Listing

    We also examined lands that were historically occupied by both 
species, but where we are uncertain of the current occupancy, or that 
are currently unoccupied. These units were all occupied within the past 
20 years (had records in 1993 or more recently) and are essential for 
the conservation of the species. Some units may have multiple landowner 
types.
    The criteria for selecting unoccupied sites and areas where we are 
uncertain of the occupancy as critical habitat are: (1) Type, amount, 
and quality of habitat associated with those occurrences (e.g., high-
quality native remnant prairies); (2) presence of the physical or 
biological features essential for the species; (3) no known appreciable 
degradation in habitat quality since the species was last detected; (4) 
prairies where known threats to the species are few and could feasibly 
be alleviated (e.g., by modifying grazing practices or controlling 
invasive species) through conservation measures; (5) prairies where 
there is reasonable potential for survival of the species if 
reoccupation were to occur, either by natural means through dispersal 
from currently occupied sites or by future reintroduction efforts; and 
(6) prairies currently occupied by other remnant prairie-dependent 
butterfly species, (e.g., Dakota skipper, Poweshiek skipperling, Ottoe 
skipper, Leonard's skipper, or regal fritillary) that share essential 
habitat features with the species. These areas outside the geographical 
area currently occupied by the Dakota skipper and Poweshiek skipperling 
that were historically occupied are essential for the conservation of 
the species.
    For unoccupied areas, and areas where we are uncertain of the 
occupancy of the species, we considered areas containing plant 
communities

[[Page 63644]]

classified as (or based on the best available information and recent 
aerial photography) dry prairie, dry-mesic prairie, mesic prairie, or 
wet-mesic remnant (untilled) prairie as potential suitable habitat for 
Dakota skipper and Poweshiek skipperling. Prairie fens, as defined by 
the MNFI, were also considered as potential suitable habitat for 
Poweshiek skipperling in Michigan. Using state natural heritage 
rankings, habitat information from recent reports, and expert 
knowledge, we selected areas with habitat quality ratings of fair to 
excellent because these areas are most likely to contain the physical 
or biological features essential for the conservation of the species. 
In some cases the habitat was not given a quality rating, but instead 
the site was given an estimated population viability rating, in recent 
reports or heritage databases, which directly reflect the quality of 
the habitat (e.g., excellent population viability rating indicates the 
presence of hig- quality native-prairie habitat). Therefore, we 
selected sites with viability ranks of fair to excellent from the most 
recent reports available because these areas are recognized to contain 
the physical or biological features essential for the conservation of 
the species. As discussed above in the Physical or Biological Features 
section of this proposal, one physical or biological feature essential 
for the conservation of the species is grassland-dominated areas that 
are necessary for dispersal between higher quality prairies. Therefore, 
we also considered including areas that contain potential dispersal 
habitat to connect patches of higher quality native prairies that are 
(1) lesser quality (or unrated) native dry-mesic prairie, mesic 
prairie, or wet-mesic remnant prairies or other habitat types such as 
wet meadow, oak savannas, and other types of grassland-dominated areas 
(e.g., not row crops or dense forests) suitable for dispersal and (2) 
within 1 km (0.6 mi) of higher (fair to excellent) quality native 
prairie.

Mapping of Proposed Critical Habitat Units

    The following steps to map potential critical habitat areas were 
taken separately for each species. First we mapped all known locations 
(points and polygons) of each species in ArcGIS and divided them into 
occupied and other (either unoccupied (areas with extirpated or 
possibly extirpated occupancy) or areas where we were uncertain of the 
occupancy (areas with unknown occupancy) using the definitions above 
and the population status provided in the ``Background'' section of the 
proposed listing rule.

Mapping of Occupied Critical Habitat Units

    Mapping occupied units was conducted separately for the two 
species; however, the general procedure was the same for both species. 
The following describes our mapping procedure for occupied areas. 
Occupied areas contain the physical and biological features essential 
for the conservation of the Dakota skipper or Poweshiek skipperling.
    Using state natural heritage rankings, habitat information from 
recent reports and expert knowledge, as described in more detail above, 
we chose occupied sites with quality prairie habitat ratings of fair to 
excellent or population viability ratings of fair to excellent, which 
directly reflects the habitat quality. If habitat at a site was not 
previously defined (e.g., we had a point or transect location for the 
butterfly survey, but the boundaries of the suitable habitat were not 
mapped in such a way to define the entire area of suitable habitat such 
as a mapped polygon in a survey report), a circle with a radius of 1 km 
(0.6 mi) [776 ac (314 ha)] (estimated dispersal distance) was 
circumscribed around each occurrence point location; the area within 
the circle was then examined for possible suitable habitat. Polygons 
were drawn around areas that contain the features essential to the 
conservation of the species. We conducted aerial photograph 
interpretation using the National Agriculture Imagery Program (NAIP) 
aerial imagery, which was acquired during the 2010-2011 agricultural 
growing seasons, to draw and refine polygons around areas that contain 
the physical or biological features essential for the conservation of 
the species. If available, we also used state natural heritage plant 
community, natural feature polygons, and other habitat mapping 
information to help refine habitat polygons.
    Areas containing plant communities classified as dry prairie, dry-
mesic prairie, mesic prairie, or wet-mesic prairie as defined by the 
MNFI, Minnesota Department of Natural Resources (MN DNR) (Michigan 
Natural Features Inventory 2012, Minnesota Department of Natural 
Resources 2012b, a), recent reports, and expert knowledge are mapped as 
potentially suitable habitat for Dakota skipper and Poweshiek 
skipperling, and these areas with fair to excellent quality habitat in 
particular contain the features essential to the conservation of the 
species and were included in polygons. Prairie fens, as defined by the 
MNFI (Michigan Natural Features Inventory 2012), also contain the 
features essential for the conservation of Poweshiek skipperling in 
Michigan; these areas with fair to excellent quality habitat in 
particular contain the features essential to the conservation of the 
species. Patches of wet meadow, oak savannas, and other grassland-
dominated prairies contain features essential to the conservation of 
the species because they provide dispersal habitat between patches of 
higher quality habitat and, therefore, were also included in the 
polygons. Patches of grassland-dominated habitats that are lower 
quality or have not been given a habitat quality rating also contain 
features essential to the conservation of the species--these areas 
provide for dispersal between higher quality prairies. To the maximum 
extent possible, converted areas (e.g., row crops and housing 
developments) were excluded from the suitable habitat mapped polygons, 
as described below in this section.
    Dakota skipper and Poweshiek skipperling may move between patches 
of prairie habitat separated by structurally similar habitats (e.g., 
perennial grasslands but not necessarily native prairie); small 
populations need immigration corridors for dispersal from nearby 
populations to prevent genetic drift and to reestablish a population 
after local extirpation. Thus, a Poweshiek skipperling or Dakota 
skipper population may require a sufficient amount of undeveloped 
dispersal habitat to ensure immigration of adults to the population 
from nearby native prairies. For this reason, if polygons were in close 
proximity to each other, buffer zones between polygons were examined 
for suitable dispersal habitat and were combined to create areas 
containing multiple prairies connected to each other by dispersal 
habitat corridors.
    After initial suitable habitat polygons were refined, we applied a 
0.5-km (0.3-mile) radius buffer (half the estimated dispersal distance) 
to each polygon. If the polygons of two or more buffers overlapped, we 
examined the areas within the buffers for potential areas of 
overlapping, contiguous dispersal habitat (e.g., prairies dominated by 
grasses, not row-crop), which was defined above as one of the essential 
physical or biological features essential to the conservation of the 
species, through aerial photograph (NAIP) interpretation and overlaying 
state natural heritage plant community and natural feature polygons, 
where available. We then combined overlapping areas of suitable 
dispersal habitat to form the proposed critical habitat polygons. 
Generally, polygons

[[Page 63645]]

separated by less than 0.6 mi (1 km) were defined as subunits of a 
larger unit encompassing those subunits, if there was a barrier to 
dispersal between the polygons. Polygons and thus critical habitat 
subunits of units may have multiple landowners. Units or subunits were 
named and numbered separately for each state.
    When determining proposed critical habitat boundaries, we made 
every effort to avoid including developed areas such as buildings, 
paved areas, and other structures that lack PCEs for the Dakota skipper 
or Poweshiek skipperling. The scale of the maps prepared under the 
parameters for publication within the Code of Federal Regulations may 
not reflect the exclusion of such developed lands. Any such lands 
inadvertently left inside critical habitat boundaries shown on the maps 
of this proposed rule have been excluded by text in the proposed rule 
and are not proposed for designation as critical habitat. Therefore, if 
the critical habitat is finalized as proposed, a Federal action 
involving these developed lands would not trigger section 7 
consultation with respect to critical habitat and the requirement of no 
adverse modification unless the specific action would affect physical 
or biological features in the adjacent critical habitat.

Mapping of Unoccupied Critical Habitat Units

    Mapping unoccupied units (and units with uncertain occupancy) was 
conducted separately for the two species; however, the general 
procedure was the same for both species. The following describes our 
mapping procedure for unoccupied units (and units with uncertain 
occupancy). As described above, we analyzed areas with uncertain 
occupancy as if they were unoccupied, in other words, using the 
standard of ``necessary for the conservation of the species'' as 
defined in the Act. Both unoccupied areas and areas where we are 
uncertain of the occupancy are necessary for the conservation of the 
Dakota skipper or Poweshiek skipperling.
    Using state natural heritage rankings, habitat information from 
recent reports and expert knowledge, as described in more detail above, 
we chose unoccupied sites (and sites with uncertain occupancy) with 
fair to excellent quality prairie habitat ratings of fair to excellent 
or population viability ratings of fair to excellent, which directly 
reflects the habitat quality, and that met our criteria as discussed 
above. If habitat at a site was not previously defined (e.g., we had a 
point or transect location for the butterfly survey, but the boundaries 
of the suitable habitat were not mapped in such a way to define the 
entire area of suitable habitat such as a mapped polygon in a survey 
report), a circle with a radius of 1 km (0.6 mi) [776 ac (314 ha)] 
(estimated dispersal distance) was circumscribed around each occurrence 
point location; the area within the circle was then examined for 
possible suitable habitat. Polygons were drawn around areas that were 
considered to be essential to the conservation of the species. We 
conducted aerial photograph interpretation using the National 
Agriculture Imagery Program (NAIP) aerial imagery, which was acquired 
during the 2010-2011 agricultural growing seasons, to draw and refine 
polygons around areas considered to be essential to the conservation of 
the species. If available, we also used state natural heritage plant 
community, natural feature polygons, and other habitat mapping 
information to help refine habitat polygons. Areas containing plant 
communities classified as dry prairie, dry-mesic prairie, mesic 
prairie, or wet-mesic prairie as defined by the MNFI, MN DNR (Michigan 
Natural Features Inventory 2012, Minnesota Department of Natural 
Resources 2012b, a), recent reports, and expert knowledge are mapped as 
potentially suitable habitat for Dakota skipper and Poweshiek 
skipperling, and these areas with fair to excellent quality habitat in 
particular were considered to be essential to the conservation of the 
species. Prairie fens, as defined by the MNFI (Michigan Natural 
Features Inventory 2012), are essential for the conservation of the 
Poweshiek skipperling in Michigan, particularly these areas with fair 
to excellent quality habitat.
    Patches of wet meadow, oak savannas, and other grassland-dominated 
prairies are also considered to be essential to the conservation of the 
species, primarily because these areas provide the species with 
dispersal habitat between patches of higher quality prairie; therefore, 
these areas were also included in the mapped polygons. Patches of 
grassland-dominated habitats that are lower quality or have not been 
given a habitat quality rating are also considered to be essential to 
the conservation of the species, primarily because these areas provide 
the species with patches of dispersal habitat between patches of higher 
quality habitat. To the maximum extent possible, converted areas (e.g., 
row crops and housing developments) were excluded from the mapped 
polygons, as described below in this section.
    Dakota skipper and Poweshiek skipperling may move between patches 
of prairie habitat separated by structurally similar habitats (e.g., 
perennial grasslands but not necessarily native prairie); small 
populations need immigration corridors for dispersal from nearby 
populations to prevent genetic drift and to reestablish a population 
after local extirpation. Thus, a Poweshiek skipperling or Dakota 
skipper population may require a sufficient amount of undeveloped 
dispersal habitat to ensure immigration of adults to the population 
from nearby native prairies. For this reason, if polygons were in close 
proximity to each other, buffer zones between polygons were examined 
for suitable dispersal habitat and were combined to create areas 
containing multiple prairies connected to each other by dispersal 
habitat corridors. Dispersal areas, which connect native-prairie 
habitats, are essential to the conservation of the species.
    After initial suitable habitat polygons were refined, we applied a 
0.5-km (0.3-mile) radius buffer (half the estimated dispersal distance) 
to each polygon. If two or more buffer polygons overlapped, we examined 
the areas within the buffers for potential areas of overlapping, 
contiguous dispersal habitat (e.g., prairies dominated by grasses, not 
row-crop) through aerial photograph (NAIP) interpretation and 
overlaying state natural heritage plant community and natural feature 
polygons, where available. We then combined overlapping areas of 
suitable dispersal habitat to form the proposed critical habitat 
polygons.
    Generally, polygons separated by less than 0.6 mi (1 km) were 
defined as subunits of a larger unit encompassing those subunits, if 
there was a barrier to dispersal between the polygons. Polygons and 
thus critical habitat subunits of units may have multiple landowners. 
Units or subunits were named and numbered separately for each state.
    When determining proposed critical habitat boundaries, we made 
every effort to avoid including developed areas such as buildings, 
paved areas, and other structures that lack PCEs for the Dakota skipper 
or Poweshiek skipperling. The scale of the maps prepared under the 
parameters for publication within the Code of Federal Regulations may 
not reflect the exclusion of such developed lands. Any such lands 
inadvertently left inside critical habitat boundaries shown on the maps 
of this proposed rule have been

[[Page 63646]]

excluded by text in the proposed rule and are not proposed for 
designation as critical habitat. Therefore, if the critical habitat is 
finalized as proposed, a Federal action involving these developed lands 
would not trigger section 7 consultation with respect to critical 
habitat and the requirement of no adverse modification unless the 
specific action would affect physical or biological features in the 
adjacent critical habitat.
    We are proposing for designation of critical habitat lands that we 
have determined are occupied at the time of listing and contain 
sufficient elements of physical or biological features to support life-
history processes essential for the conservation of the species, and 
lands outside of the geographical area occupied at the time of listing 
that we have determined are essential for the conservation of Dakota 
skipper and Poweshiek skipperling.
    Units were proposed for designation based on sufficient elements of 
physical or biological features being present to support Dakota skipper 
and Poweshiek skipperling life-history processes. Some units contained 
all of the identified elements of physical or biological features and 
supported multiple life-history processes. Some units contained only 
some elements of the physical or biological features necessary to 
support the Dakota skipper and Poweshiek skipperling particular use of 
that habitat.
    The critical habitat designation is defined by the map or maps, as 
modified by any accompanying regulatory text, presented at the end of 
this document in the rule portion. We include more detailed information 
on the boundaries of the critical habitat designation in the preamble 
of this document. We will make the coordinates or plot points or both 
on which each map is based and detailed textual descriptions of each 
unit or subunit available to the public on https://www.regulations.gov 
at Docket No. FWS-R3-ES-2013-0017, on our Internet site https://www.fws.gov/midwest/Endangered, and at the Twin Cities Field Office 
(see FOR FURTHER INFORMATION CONTACT above).

Proposed Critical Habitat Designation

Dakota Skipper

    For the Dakota skipper, we are proposing for designation of 
critical habitat lands that we have determined are occupied at the time 
of listing and contain sufficient elements of the physical or 
biological features necessary to support life-history processes 
essential for the conservation of the species. We are also proposing 
lands outside of the geographical area occupied at the time of listing 
that we have determined are essential for the conservation of Dakota 
skipper. Due to their small numbers of individuals or low population 
sizes, suitable habitat and space for expansion or reintroduction are 
essential to achieve population levels necessary for recovery.
    We are proposing 51 areas as critical habitat for the Dakota 
skipper: (1) DS Minnesota Units 1 through 15, (2) DS North Dakota Units 
1 through 14, and (3) DS South Dakota Units 1 through 22. The occupancy 
status of all units is listed in Table 1. Table 1 shows the primary 
type of ownership and approximate area of each proposed critical 
habitat unit. Each unit contains all of the primary constituent 
elements of the physical or biological features essential to the 
conservation of the Dakota skipper, unless otherwise noted.

 Table 1--Proposed Critical Habitat Units for Dakota Skipper--Area Estimates Reflect All Land Within Critical Habitat Unit Boundaries--Note: Area Sizes
  May Not Sum Due to Rounding--Detailed Unit Descriptions Are Posted at https://www.regulations.gov and Can Be Found at Docket No. FWS-R3-ES-2013-0017--
  Some Units May Have Multiple Landowner Types; the Primary Landowner Column Gives the Type of Owner With the Most Land Area in Each Unit--Occupancy of
Each Proposed Unit Is Noted as Either Occupied (Yes) or Unoccupied (No)--Units With Uncertain Occupancy Are Noted as Unoccupied (No) as They Are Treated
         as Such for the Purposes of This Critical Habitat Proposal--The Primary Constituent Elements (PCEs) Present in Each Unit Are Also Given
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                         Primary
                  State                               County               Critical habitat unit name       Area in     landowner     Occupied     PCE
                                                                                                           acres (ha)     (type)
--------------------------------------------------------------------------------------------------------------------------------------------------------
MN.......................................  Pope.......................  DS Minnesota Unit 1.............        2,887        State          Yes  1, 2, 3
                                                                                                              (1,168)
MN.......................................  Murray.....................  DS Minnesota Unit 2.............    905 (366)      Private          Yes  1, 2, 3
MN.......................................  Murray.....................  DS Minnesota Unit 3.............     126 (51)      Private           No     1, 2
MN.......................................  Clay.......................  DS Minnesota Unit 4.............  1,875 (759)  Consv. Org.          Yes     1, 2
MN.......................................  Clay.......................  DS Minnesota Unit 5.............  1,470 (595)      Private          Yes  1, 2, 3
MN.......................................  Norman.....................  DS Minnesota Unit 6.............    275 (111)  Consv. Org.           No     1, 2
MN.......................................  Lincoln....................  DS Minnesota Unit 7A............  1,312 (531)        State           No     1, 2
MN.......................................  Lincoln....................  DS Minnesota Unit 7B............      92 (37)  Consv. Org.           No     1, 2
MN.......................................  Lincoln....................  DS Minnesota Unit 7C............     149 (60)  Consv. Org.           No     1, 2
MN.......................................  Pipestone..................  DS Minnesota Unit 8.............    352 (143)        State           No     1, 2
MN.......................................  Pipestone..................  DS Minnesota Unit 9.............    416 (168)        State          Yes     1, 2
MN.......................................  Swift/Chippewa.............  DS Minnesota Unit 10............    967 (392)        State           No  1, 2, 3
MN.......................................  Pipestone..................  DS Minnesota Unit 11............     197 (80)        State           No     1, 2
MN.......................................  Lincoln....................  DS Minnesota Unit 12............    549 (222)      Private          Yes     1, 2
MN.......................................  Kittison...................  DS Minnesota Unit 13A...........      38 (16)        State           No     1, 2
MN.......................................  Kittison...................  DS Minnesota Unit 13B...........     224 (91)        State           No     1, 2
MN.......................................  Polk.......................  DS Minnesota Unit 14............    842 (341)        State           No     1, 2
MN.......................................  Polk.......................  DS Minnesota Unit 15............    268 (108)  Consv. Org.           No     1, 2
ND.......................................  Richland...................  DS North Dakota Unit 1..........     119 (48)      Federal           No     1, 2
ND.......................................  Ransom.....................  DS North Dakota Unit 2..........    949 (348)      Federal           No  1, 2, 3
ND.......................................  McHenry....................  DS North Dakota Unit 3..........  1,526 (618)      Private          Yes  1, 2, 3
ND.......................................  McHenry....................  DS North Dakota Unit 4..........     197 (80)      Private          Yes     1, 2
ND.......................................  McHenry....................  DS North Dakota Unit 5..........  2,446 (990)      Private          Yes  1, 2, 3
ND.......................................  McHenry....................  DS North Dakota Unit 6..........      80 (33)        State          Yes     1, 2
ND.......................................  McHenry....................  DS North Dakota Unit 7..........    280 (113)      Private          Yes     1, 2

[[Page 63647]]

 
ND.......................................  McHenry....................  DS North Dakota Unit 8..........    448 (181)        State          Yes  1, 2, 3
ND.......................................  Rolette....................  DS North Dakota Unit 9..........    514 (208)      Private           No  1, 2, 3
ND.......................................  McKenzie...................  DS North Dakota Unit 10.........    639 (259)       Tribal           No  1, 2, 3
ND.......................................  McKenzie...................  DS North Dakota Unit 11.........    418 (169)      Federal          Yes     1, 2
ND.......................................  McKenzie...................  DS North Dakota Unit 12.........    309 (125)      Federal          Yes     1, 2
ND.......................................  Ransom.....................  DS North Dakota Unit 13.........    727 (294)      Federal          Yes     1, 2
ND.......................................  Wells......................  DS North Dakota Unit 14.........     242 (98)      Private          Yes     1, 2
SD.......................................  Marshall...................  DS South Dakota Unit 1..........    451 (183)      Federal           No     1, 2
SD.......................................  Brookings..................  DS South Dakota Unit 2..........     169 (68)        State          Yes     1, 2
SD.......................................  Deuel......................  DS South Dakota Unit 3..........    516 (209)        State           No     1, 2
SD.......................................  Grant......................  DS South Dakota Unit 4..........    292 (118)      Federal          Yes     1, 2
SD.......................................  Deuel......................  DS South Dakota Unit 5..........     119 (48)      Federal           No     1, 2
SD.......................................  Roberts....................  DS South Dakota Unit 6..........      31 (13)        State          Yes     1, 2
SD.......................................  Roberts....................  DS South Dakota Unit 7..........    470 (190)       Tribal          Yes  1, 2, 3
SD.......................................  Roberts....................  DS South Dakota Unit 8..........    501 (203)      Federal          Yes  1, 2, 3
SD.......................................  Roberts....................  DS South Dakota Unit 9..........     160 (65)       Tribal          Yes  1, 2, 3
SD.......................................  Roberts....................  DS South Dakota Unit 10.........     117 (47)       Tribal          Yes     1, 2
SD.......................................  Roberts....................  DS South Dakota Unit 11.........      89 (36)       Tribal          Yes     1, 2
SD.......................................  Day........................  DS South Dakota Unit 12.........    531 (215)       Tribal          Yes  1, 2, 3
SD.......................................  Day........................  DS South Dakota Unit 13.........      56 (23)      Private           No     1, 2
SD.......................................  Day........................  DS South Dakota Unit 14.........     189 (76)       Tribal          Yes     1, 2
SD.......................................  Day........................  DS South Dakota Unit 15.........     188 (76)        State           No  1, 2, 3
SD.......................................  Roberts....................  DS South Dakota Unit 16.........    348 (141)      Federal           No  1, 2, 3
SD.......................................  Roberts....................  DS South Dakota Unit 17.........    552 (223)      Federal          Yes     1, 2
SD.......................................  Marshall/..................  DS South Dakota Unit 18.........     216 (87)      Federal           No     1, 2
                                           Roberts....................
SD.......................................  Roberts....................  DS South Dakota Unit 19.........    363 (147)      Private          Yes     1, 2
SD.......................................  Brookings..................  DS South Dakota Unit 20.........    255 (103)      Private          Yes     1, 2
SD.......................................  Brookings..................  DS South Dakota Unit 21.........     198 (80)      Private          Yes     1, 2
SD.......................................  Brookings..................  DS South Dakota Unit 22.........     133 (54)      Private          Yes     1, 2
--------------------------------------------------------------------------------------------------------------------------------------------------------

Poweshiek Skipperling

    For the Poweshiek skipperling, we are proposing for designation as 
critical habitat lands that we have determined are occupied at the time 
of listing and contain sufficient elements of the physical or 
biological features necessary to support life-history processes 
essential for the conservation of the species. We are also proposing 
lands outside of the geographical area occupied at the time of listing 
(unoccupied lands) that we have determined are essential for the 
conservation of the Poweshiek skipperling because it provides the 
features necessary for the reestablishment of wild populations within 
their historical range. Due to their small numbers of individuals or 
low population sizes, suitable habitat and space for expansion or 
reintroduction are essential to achieving population levels necessary 
for recovery of the species.
    We are proposing 61 areas as critical habitat for the Poweshiek 
skipperling: (1) PS Iowa Units 1 through 11, (2) PS Michigan Units 1 
through 9, (3) PS Minnesota Units 1 through 18, (4) PS North Dakota 
Units 1 through 3, (5) PS South Dakota Units 1 through 18, and (6) PS 
Wisconsin Units 1 and 2. All critical habitat units are occupied by 
Poweshiek skipperling unless otherwise stated. Table 2 shows the 
primary type of ownership and approximate area of each proposed 
critical habitat unit.

[[Page 63648]]



Table 2--Proposed Critical Habitat Units for Poweshiek Skipperling, With Occupancy and Size Information--Area Estimates Reflect All Land Within Critical
Habitat Unit Boundaries--Note: Area Sizes May Not Sum Due to Rounding--Detailed Unit Descriptions Are Posted at https://www.regulations.gov in Docket No.
 FWS-R3-ES-2013-0017--Some Units May Have Multiple Landowner Types--The Primary Landowner Column Gives the Type of Owner With the Most Land Area in Each
Unit--Occupancy of Each Proposed Unit Is Noted as Either Occupied (Yes), Unoccupied (No)--Units With Uncertain Occupancy Are Noted as Unoccupied (No) as
They Are Treated as Such for the Purposes of This Critical Habitat Proposal--The Primary Constituent Elements (PCEs) Present in Each Unit Are Also Given
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                         Primary
                  State                               County               Critical habitat unit name       Area in     landowner     Occupied     PCE
                                                                                                           acres (ha)     (type)
--------------------------------------------------------------------------------------------------------------------------------------------------------
IA.......................................  Howard.....................  PS Iowa Unit 1..................     237 (96)        State           No     1, 3
IA.......................................  Cerro Gordo................  PS Iowa Unit 2..................      34 (14)  Consv. Org.           No     1, 3
IA.......................................  Dickinson..................  PS Iowa Unit 3..................     136 (55)  Consv. Org.           No     1, 3
IA.......................................  Dickinson..................  PS Iowa Unit 4..................    755 (306)        State           No  1, 3, 4
IA.......................................  Osceola....................  PS Iowa Unit 5..................      75 (30)      Private           No  1, 3, 4
IA.......................................  Dickinson..................  PS Iowa Unit 6..................      79 (32)        State           No     1, 3
IA.......................................  Dickinson..................  PS Iowa Unit 7..................     146 (59)        State           No     1, 3
IA.......................................  Osceola....................  PS Iowa Unit 8..................     205 (83)      Private           No     1, 3
IA.......................................  Dickinson..................  PS Iowa Unit 9..................    312 (126)      Private           No     1, 3
IA.......................................  Kossuth....................  PS Iowa Unit 10.................     139 (56)      Private           No     1, 3
IA.......................................  Emmet......................  PS Iowa Unit 11.................    272 (110)        State           No     1, 3
MI.......................................  Oakland....................  PS Michigan Unit 1..............      25 (10)        State          Yes     2, 3
MI.......................................  Oakland....................  PS Michigan Unit 2..............      66 (27)        State          Yes     2, 3
MI.......................................  Oakland....................  PS Michigan Unit 3..............    456 (184)      Private          Yes  2, 3, 4
MI.......................................  Oakland....................  PS Michigan Unit 4..............    369 (149)      Private          Yes     2, 3
MI.......................................  Livingston.................  PS Michigan Unit 5..............      23 (10)      Private           No     2, 3
MI.......................................  Washtenaw..................  PS Michigan Unit 6..............    268 (109)       County          Yes     2, 3
MI.......................................  Lenawee....................  PS Michigan Unit 7..............     123 (50)  Consv. Org.          Yes     2, 3
MI.......................................  Jackson/Hilsdale...........  PS Michigan Unit 8..............    363 (147)      Private          Yes  2, 3, 4
MI.......................................  Jackson....................  PS Michigan Unit 9..............      34 (14)      Private          Yes     2, 3
MN.......................................  Pope.......................  PS Minnesota Unit 1.............        2,887        State           No  1, 3, 4
                                                                                                               (1168)
MN.......................................  Murray.....................  PS Minnesota Unit 2.............    905 (366)      Private           No  1, 3, 4
MN.......................................  Murray.....................  PS Minnesota Unit 3.............     126 (51)      Private           No     1, 3
MN.......................................  Clay.......................  PS Minnesota Unit 4.............  1,875 (759)  Consv. Org.           No     1, 3
MN.......................................  Clay.......................  PS Minnesota Unit 5.............  1,470 (595)      Private           No  1, 3, 4
MN.......................................  Norman.....................  PS Minnesota Unit 6.............    275 (111)        State           No     1, 3
MN.......................................  Lincoln....................  PS Minnesota Unit 7.............  1,312 (531)        State           No  1, 3, 4
MN.......................................  Pipestone..................  PS Minnesota Unit 8.............    352 (143)        State           No     1, 3
MN.......................................  Pipestone..................  PS Minnesota Unit 9.............    416 (168)        State           No     1, 3
MN.......................................  Swift/Chippewa.............  DS Minnesota Unit 10............    967 (392)        State           No  1, 3, 4
MN.......................................  Wilkin.....................  PS Minnesota Unit 11............    437 (177)  Consv. Org.           No  1, 3, 4
MN.......................................  Lyon.......................  PS Minnesota Unit 12............    274 (111)        State           No     1, 3
MN.......................................  La Qui Parle...............  PS Minnesota Unit 13............    525 (212)  Consv. Org.           No     1, 3
MN.......................................  Douglas....................  PS Minnesota Unit 14............      90 (36)  Consv. Org.           No     1, 3
MN.......................................  Mahnomen...................  PS Minnesota Unit 15............  1,369 (554)        State           No     1, 3
MN.......................................  Cottonwood.................  PS Minnesota Unit 16............     239 (97)        State           No     1, 3
MN.......................................  Pope.......................  PS Minnesota Unit 17............    431 (174)  Consv. Org.           No     1, 3
MN.......................................  Clay.......................  PS Minnesota Unit 18............    466 (189)  Consv. Org.           No     1, 3
ND.......................................  Richland...................  PS North Dakota Unit 1..........     119 (48)      Federal           No     1, 3
ND.......................................  Richland...................  PS North Dakota Unit 2..........      47 (19)      Federal           No     1, 3
ND.......................................  Sargent....................  PS North Dakota Unit 3..........     117 (47)      Federal           No     1, 3
SD.......................................  Marshall...................  PS South Dakota Unit 1..........     451(183)      Federal           No     1, 3
SD.......................................  Brookings..................  PS South Dakota Unit 2..........     169 (68)        State           No     1, 3
SD.......................................  Deuel......................  PS South Dakota Unit 3A.........    516 (209)        State           No     1, 3
SD.......................................  Deuel......................  PS South Dakota Unit 3B.........    582 (236)        State           No     1, 3
SD.......................................  Grant......................  PS South Dakota Unit 4..........    292 (118)      Federal           No     1, 3
SD.......................................  Deuel......................  PS South Dakota Unit 5..........     119 (48)      Federal           No     1, 3
SD.......................................  Roberts....................  PS South Dakota Unit 6..........      31 (13)        State           No     1, 3
SD.......................................  Roberts....................  PS South Dakota Unit 7..........    470 (190)       Tribal           No  1, 3, 4
SD.......................................  Roberts....................  PS South Dakota Unit 8..........    501 (203)      Federal           No  1, 3, 4
SD.......................................  Roberts....................  PS South Dakota Unit 9..........     160 (65)       Tribal           No  1, 3, 4
SD.......................................  Roberts....................  PS South Dakota Unit 10.........     117 (47)       Tribal           No     1, 3
SD.......................................  Roberts....................  PS South Dakota Unit 11.........      89 (36)       Tribal           No     1, 3
SD.......................................  Day........................  PS South Dakota Unit 12.........    676 (274)       Tribal           No  1, 3, 4
SD.......................................  Day........................  PS South Dakota Unit 13.........      56 (23)      Private           No     1, 3
SD.......................................  Day........................  PS South Dakota Unit 14.........     189 (76)       Tribal           No     1, 3
SD.......................................  Day........................  PS South Dakota Unit 15.........     188 (76)        State           No  1, 3, 4
SD.......................................  Day........................  PS South Dakota Unit 16.........    348 (141)      Federal           No  1, 3, 4
SD.......................................  Moody......................  PS South Dakota Unit 17.........     198 (80)  Consv. Org.           No     1, 3
SD.......................................  Marshall...................  PS South Dakota Unit 18.........    401 (162)      Federal           No     1, 3
WI.......................................  Waukesha...................  PS Wisconsin Unit 1.............  1,535 (621)        State          Yes  1, 3, 4

[[Page 63649]]

 
WI.......................................  Green Lake.................  PS Wisconsin Unit 2.............    280 (113)        State          Yes     1, 3
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note: Area sizes may not sum due to rounding.

Effects of Critical Habitat Designation

Section 7 Consultation

    Section 7(a)(2) of the Act requires Federal agencies, including the 
Service, to ensure that any action they fund, authorize, or carry out 
is not likely to jeopardize the continued existence of any endangered 
species or threatened species or result in the destruction or adverse 
modification of designated critical habitat of such species. In 
addition, section 7(a)(4) of the Act requires Federal agencies to 
confer with the Service on any agency action that is likely to 
jeopardize the continued existence of any species proposed to be listed 
under the Act or result in the destruction or adverse modification of 
proposed critical habitat.
    Decisions by the 5th and 9th Circuit Courts of Appeals have 
invalidated our regulatory definition of ``destruction or adverse 
modification'' (50 CFR 402.02) (see Gifford Pinchot Task Force v. U.S. 
Fish and Wildlife Service, 378 F. 3d 1059 (9th Cir. 2004) and Sierra 
Club v. U.S. Fish and Wildlife Service et al., 245 F.3d 434, 442 (5th 
Cir. 2001)), and we do not rely on this regulatory definition when 
analyzing whether an action is likely to destroy or adversely modify 
critical habitat. Under the statutory provisions of the Act, we 
determine destruction or adverse modification on the basis of whether, 
with implementation of the proposed Federal action, the affected 
critical habitat would continue to serve its intended conservation role 
for the species.
    If a Federal action may affect a listed species or its critical 
habitat, the responsible Federal agency (action agency) must enter into 
consultation with us. Examples of actions that are subject to the 
section 7 consultation process are actions on State, tribal, local, or 
private lands that require a Federal permit (such as a permit from the 
U.S. Army Corps of Engineers under section 404 of the Clean Water Act 
(33 U.S.C. 1251 et seq.) or a permit from the Service under section 10 
of the Act) or that involve some other Federal action (such as funding 
from the U.S. Department of Agriculture, Natural Resources Conservation 
Service, Farm Service Agency, Rural Development, Rural Utilities 
Service, Federal Highway Administration, Federal Aviation 
Administration, or the Federal Emergency Management Agency). Federal 
actions not affecting listed species or critical habitat, and actions 
on State, tribal, local, or private lands that are not federally funded 
or authorized, do not require section 7 consultation.
    As a result of section 7 consultation, we document compliance with 
the requirements of section 7(a)(2) through our issuance of:
    (1) A concurrence letter for Federal actions that may affect, but 
are not likely to adversely affect, listed species or critical habitat; 
or
    (2) A biological opinion for Federal actions that may affect, or 
are likely to adversely affect, listed species or critical habitat.
    When we issue a biological opinion concluding that a project is 
likely to jeopardize the continued existence of a listed species and/or 
destroy or adversely modify critical habitat, we provide reasonable and 
prudent alternatives to the project, if any are identifiable, that 
would avoid the likelihood of jeopardy and/or destruction or adverse 
modification of critical habitat. We define ``reasonable and prudent 
alternatives'' (at 50 CFR 402.02) as alternative actions identified 
during consultation that:
    (1) Can be implemented in a manner consistent with the intended 
purpose of the action,
    (2) Can be implemented consistent with the scope of the Federal 
agency's legal authority and jurisdiction,
    (3) Are economically and technologically feasible, and
    (4) Would, in the Director's opinion, avoid the likelihood of 
jeopardizing the continued existence of the listed species and/or avoid 
the likelihood of destroying or adversely modifying critical habitat.
    Reasonable and prudent alternatives can vary from slight project 
modifications to extensive redesign or relocation of the project. Costs 
associated with implementing a reasonable and prudent alternative are 
similarly variable.
    Regulations at 50 CFR 402.16 require Federal agencies to reinitiate 
consultation on previously reviewed actions in instances where we have 
listed a new species or subsequently designated critical habitat that 
may be affected and the Federal agency has retained discretionary 
involvement or control over the action (or the agency's discretionary 
involvement or control is authorized by law). Consequently, Federal 
agencies sometimes may need to request reinitiation of consultation 
with us on actions for which formal consultation has been completed, if 
those actions with discretionary involvement or control may affect 
subsequently listed species or designated critical habitat.

Application of the ``Adverse Modification'' Standard

    The key factor related to the adverse modification determination is 
whether, with implementation of the proposed Federal action, the 
affected critical habitat would continue to serve its intended 
conservation role for the species. Activities that may destroy or 
adversely modify critical habitat are those that alter the physical or 
biological features to an extent that appreciably reduces the 
conservation value of critical habitat for the Dakota skipper and 
Poweshiek skipperling. As discussed above, the role of critical habitat 
is to support life-history needs of

[[Page 63650]]

the species and provide for the conservation of these species.
    Section 4(b)(8) of the Act requires us to briefly evaluate and 
describe, in any proposed or final regulation that designates critical 
habitat, activities involving a Federal action that may destroy or 
adversely modify such habitat, or that may be affected by such 
designation.
    Activities that may affect critical habitat, when carried out, 
funded, or authorized by a Federal agency, should result in 
consultation for the Dakota skipper and Poweshiek skipperling. These 
activities include, but are not limited to:
    (1) Actions that would significantly alter the native plant 
community such that native grasses or flowering forbs are not readily 
available during the adult flight period or larval stages in the life 
cycle of the species. Such activities could include, but are not 
limited to, conversion to agriculture or other nonagricultural 
development, heavy grazing, haying prior to July 15, spraying of 
herbicides or pesticides, and fire. These activities could eliminate or 
reduce the habitat necessary for the growth and reproduction of these 
species by reducing larval and adult food sources that could result in 
direct or indirect adverse effects to individuals and their life 
cycles.
    (2) Actions that would significantly disturb the unplowed 
(untilled) soils and thereby reduce the native plant community and 
increase the nonnative plant and woody vegetation within the prairie 
habitat. Such activities could include, but are not limited to, plowing 
(tilling), heavy grazing, mining, development, and other disturbances 
to the soil such that the native plant community is reduced and the 
encroachment of nonnative plants and woody vegetation can outcompete 
native plants. These activities can result in the loss of the native 
plant community necessary for adult and larval food sources to levels 
below the tolerances of the species.
    (3) Actions that would significantly alter the hydrology of the 
prairie or prairie fen habitat. Such activities could include but are 
not limited to water withdrawal or diversion, agricultural tilling, 
urban development, mining, and dredging. These activities may lead to 
changes in water levels that would degrade or eliminate the native-
prairie plants and their habitats to levels that are beyond the 
tolerances of the species.

Exemptions

Application of Section 4(a)(3) of the Act

    Section 4(a)(3)(B)(i) of the Act (16 U.S.C. 1533(a)(3)(B)(i)) 
provides that: ``The Secretary shall not designate as critical habitat 
any lands or other geographic areas owned or controlled by the 
Department of Defense, or designated for its use, that are subject to 
an integrated natural resources management plan [INRMP] prepared under 
section 101 of the Sikes Act (16 U.S.C. 670a), if the Secretary 
determines in writing that such plan provides a benefit to the species 
for which critical habitat is proposed for designation.'' There are no 
Department of Defense lands with a completed INRMP within the proposed 
critical habitat designation.

Exclusions

Application of Section 4(b)(2) of the Act

    Section 4(b)(2) of the Act states that the Secretary shall 
designate and make revisions to critical habitat on the basis of the 
best available scientific data after taking into consideration the 
economic impact, the impact on national security, and any other 
relevant impact of specifying any particular area as critical habitat. 
The Secretary may exclude an area from critical habitat if she 
determines that the benefits of such exclusion outweigh the benefits of 
specifying such area as part of the critical habitat, unless she 
determines, based on the best scientific data available, that the 
failure to designate such area as critical habitat will result in the 
extinction of the species. In making that determination, the statute on 
its face, as well as the legislative history, are clear that the 
Secretary has broad discretion regarding which factor(s) to use and how 
much weight to give to any factor.
    Under section 4(b)(2) of the Act, we may exclude an area from 
designated critical habitat based on economic impacts, impacts on 
national security, or any other relevant impacts. In considering 
whether to exclude a particular area from the designation, we identify 
the benefits of including the area in the designation, identify the 
benefits of excluding the area from the designation, and evaluate 
whether the benefits of exclusion outweigh the benefits of inclusion. 
If the analysis indicates that the benefits of exclusion outweigh the 
benefits of inclusion, the Secretary may exercise her discretion to 
exclude the area only if such exclusion would not result in the 
extinction of the species. Therefore, and as discussed in more detail 
below, we are seeking any and all relevant information relating to the 
possible exclusion of any particular proposed critical habitat unit. 
The potential exclusion of any number of the proposed critical habitat 
units is one logical outgrowth of this proposed rule.
Exclusions Based on Economic Impacts
    Under section 4(b)(2) of the Act, we consider the economic impacts 
of specifying any particular area as critical habitat. In order to 
consider economic impacts, we are preparing an analysis of the probable 
economic impacts of the proposed critical habitat designation and 
related factors.
    Sectors that may be affected by the proposed designation include, 
but are not limited to, private developers of residential, 
recreational, and commercial property; city, county, and State 
governments that construct and maintain roads and other infrastructure; 
private and public entities that use land for grazing and other 
agricultural purposes; Native American Tribal governments; energy 
developers, private conservation organizations; entities that mine 
gravel or other products; and wind power developers.
    We will announce the availability of the draft economic analysis as 
soon as it is completed, at which time we will seek public review and 
comment. At that time, copies of the draft economic analysis will be 
available for downloading from the Internet at https://www.regulations.gov, or by contacting the Twin Cities Ecological 
Services Field Office directly (see FOR FURTHER INFORMATION CONTACT 
section). During the development of a final designation, we will 
consider the probable economic impacts, public comments, and other new 
information, and areas may be excluded from the final critical habitat 
designation under section 4(b)(2) of the Act and our implementing 
regulations at 50 CFR 424.19.
Exclusions Based on National Security Impacts
    Under section 4(b)(2) of the Act, we consider whether there are 
lands owned or managed by the Department of Defense where a national 
security impact might exist. In preparing this proposal, we have 
determined that the lands within the proposed designation of critical 
habitat for the Dakota Skipper and Poweshiek skipperling are not owned 
or managed by the Department of Defense, and, therefore, we anticipate 
no impact on national security. Consequently, the Secretary does not 
propose to exert her discretion to exclude any areas from the final

[[Page 63651]]

designation based on impacts on national security.
Exclusions Based on Other Relevant Impacts
    Under section 4(b)(2) of the Act, we consider any other relevant 
impacts, in addition to economic impacts and impacts on national 
security. We consider a number of factors, including whether the 
landowners have developed any HCPs or other management plans for the 
area, or whether there are conservation partnerships that would be 
encouraged by designation of, or exclusion from, critical habitat. In 
addition, we look at any tribal issues, and consider the government-to-
government relationship of the United States with tribal entities. We 
also consider any social impacts that might occur because of the 
designation.
    To determine whether any non-Federal lands should be excluded from 
the final designation, we compare the benefits of designating them as 
critical habitat to the benefits to the conservation of the species and 
the physical or biological features that would likely occur as a result 
of implementing and maintaining existing and functioning management 
plans and conservation partnerships, respectively. Partnerships between 
the Service and private landowners, state conservation agencies, and 
others that are likely to facilitate the continued implementation of 
management actions that benefit the species and its habitat may provide 
as much or more benefit than might be realized as a result of 
consultation carried out under section 7(a)(2) of the Endangered 
Species Act. We must evaluate each potential exclusion on a case-by-
case basis to determine whether the benefits of exclusion may outweigh 
the benefits of inclusion with regard to the conservation and recovery 
of the listed species in question.
    When we evaluate a management plan during our consideration of the 
benefits of exclusion, we assess a variety of factors, including but 
not limited to, whether the plan is finalized, how it provides for the 
conservation of the essential physical or biological features, whether 
there is a reasonable expectation that the conservation management 
strategies and actions contained in the plan will be implemented into 
the future, whether the conservation strategies in the plan are likely 
to be effective, and whether the plan contains a monitoring program or 
adaptive management to ensure that the conservation measures are 
effective and can be adapted in the future in response to new 
information.
    Based on the information provided by entities seeking exclusion, as 
well as any additional public comments received, we will evaluate 
whether certain lands in the proposed critical habitat are appropriate 
for exclusion from the final designation under section 4(b)(2) of the 
Act. If the analysis indicates that the benefits of excluding lands 
from the final designation outweigh the benefits of designating those 
lands as critical habitat, then the Secretary may exercise her 
discretion to exclude the lands from the final designation.
    For example, some stakeholders and conservation agencies are 
concerned that designating critical habitat on private lands may harm 
existing or future conservation partnerships necessary to conserve a 
range of prairie species, including these butterflies, especially in 
light of the factors that may be relaxing some of the ``natural 
constraints'' (e.g., soil quality and slope) on conversion of prairie 
to cropland (Sylvester et al. 2013, p. 14). Continued private landowner 
acceptance of conservation programs has been identified as one of the 
most important factors that will determine whether or not efforts to 
protect prairie from conversion will succeed--more than 90 percent of 
land in the range of the Dakota skipper may be privately owned, and 
protection of remaining grassland by conservation easements is now the 
primary tool used to slow their conversion to cropland (Doherty et al. 
2013, p. 13). In an era of high commodity prices and expanding 
agricultural technological innovations, critical habitat may influence 
some owners to sell or plow their grasslands or it may erode landowner 
interest and acceptance of conservation programs, which would undermine 
butterfly and prairie conservation. At this time, we are requesting 
specific information on this topic so that we may weigh the relative 
benefits of critical habitat designation versus exclusion to the 
conservation of the species and the physical or biological features 
essential to the conservation of the species.
    We seek information regarding any and all types of conservation 
programs and plans relevant to the protection of proposed critical 
habitat units for the Dakota skipper and Poweshiek skipperling. Such 
programs and plans may include conservation easements, management 
agreements, tax incentive programs, or any other plan or program, 
particularly those programs that include specific grazing regimes and 
other management actions that benefit these species. We also note that 
the Service is not the only agency with active conservation programs 
throughout the range of these two butterflies; landowners interested in 
conserving native prairie should also consider contacting their State 
and Tribal conservation offices, as well as offices of the U.S. 
Department of Agriculture, Natural Resources Conservation Service, and 
other agencies in your area. Some examples of existing conservation 
programs and plans are provided below, though these are not intended to 
present an exhaustive list of programs that may be relevant to 
potential exclusion of proposed critical habitat from the final 
designation.
    Grassland Easements: The Service's grassland easement program began 
in 1989. With the continued conversion of grassland to cropland and 
consistent declines in the populations of grassland-dependent birds, 
the need to protect grassland habitats became evident. A grassland 
easement transfers limited perpetual rights to the Service for a one-
time, lump-sum payment; perpetual easements are bought from willing 
landowners. The program was developed and is carried out by managers, 
biologists, and realty specialists with an interest in protecting 
resources at the landscape scale. Grassland easements generally 
prohibit the cultivation of grassland habitat, while still permitting 
the landowner traditional livestock uses. Grassland easements restrict 
the landowner from altering the grass by digging, plowing, disking, or 
otherwise destroying the vegetative cover. Haying, mowing, and seed 
harvest are restricted until July 16 of each year. Grassland easements 
are inspected yearly for possible violations of the easement contract.
    The grassland easement program further advanced the philosophy of 
protecting working landscapes that provide conservation benefits in the 
agricultural environment. The Service intended the grassland easement 
and management policy to reflect a partnership between the Service and 
the surface owner of the property. Each potential easement is evaluated 
for its value to wildlife. Large native grass tracts with good wetland 
complexes are given the highest priority when Migratory Bird Treaty Act 
funds are used to purchase the easement. Land and Water Conservation 
Funds are also used to preserve northern tallgrass prairie. This 
program may benefit the Dakota skipper and Poweshiek skipperling to the 
extent that native prairie meeting the habitat needs of these species 
is protected; parcels covered by a grassland easement will be examined 
on a case-by-case basis to determine the conservation benefits of

[[Page 63652]]

this program for these two butterfly species. Landowners interested in 
participating in this program should contact the Service's Partners for 
Fish and Wildlife program in their particular state.
    Voluntary Grazing Agreements: Native prairie grasslands are the 
foundation of the ranching and livestock industry, but are increasingly 
being destroyed through conversion to row crops, such as corn and 
soybeans. Voluntary conservation programs that focus on helping 
ranchers manage their native-prairie grasslands to stay economically 
viable and preserve grassland condition are vitally important to 
maintaining grassland-dominated landscapes in North Dakota and South 
Dakota. Such conservation programs provide financial cost-share 
assistance and prescribe managed grazing on native prairie grasslands 
for periods of time varying from 3 to 10 years and provide incentives 
for ranchers to conserve wildlife habitat; this can be a benefit for 
the ranching community and the Dakota skipper and Poweshiek skipperling 
populations. Therefore, we will consider voluntary grazing agreements 
as one relevant type of conservation plan or program that may support 
excluding native-prairie grasslands from our final critical habitat 
designation. These voluntary grazing programs may benefit the Dakota 
skipper and Poweshiek skipperling to the extent that native prairie 
that meets the habitat needs of these species is protected; parcels 
covered by voluntary grazing agreements will be examined on a case-by-
case basis to determine conservation benefits of the particular grazing 
agreement to these two butterfly species. Landowners interested in 
participating in this program should contact the Service's Partners for 
Fish and Wildlife program or the USDA's Natural Resources Conservation 
Service office in their particular state.
    Minnesota's Native Prairie Tax Exemption: The Prairie Tax Exemption 
program exempts eligible lands from property taxes and is administered 
by the MN DNR in cooperation with local County Tax Assessors. To be 
considered for enrollment, landowners complete a one-page Prairie Tax 
Exemption application and submit it to the local County Assessor's 
Office with an aerial photo of the property. After a landowner has 
submitted an application, the County Assessor will contact the MN DNR, 
who will visit the property to evaluate and certify qualifying acres.
    To be eligible for Native Prairie Tax Exemption, a parcel of land 
must meet several criteria, including that it:
     Has never been plowed, cultivated, or reseeded;
     Has not been severely altered by heavy grazing or 
herbicides;
     Is dominated throughout by native-prairie vegetation with 
no, or limited, tree cover;
     Has at least 5 native-prairie species of grasses or sedges 
and 12 native-prairie forb species present;
     Is not in use as pasture (annually hayed tracts may still 
qualify); and
     Has at least 5 acres (smaller tracts with important rare 
species habitat or other significant prairie features may still 
qualify).
    This program may benefit the Dakota skipper and Poweshiek 
skipperling by providing a financial incentive to protect native 
prairie that meets habitat needs of these species. Each parcel would be 
examined on its own merits to determine the conservation benefits of 
this program.
    Minnesota Native Prairie Bank Program: This Program allows 
landowners, through a conservation easement with the MN DNR, to protect 
native prairie on their property that has never been plowed. Landowners 
receive payment for their native-prairie land while keeping it in 
private ownership. Certain agricultural practices are included in some 
easements, such as livestock grazing, mowing for hay, or harvesting of 
native seed. Because funding for the program is limited, the MN DNR 
prioritizes tracts for funding based on the quality of the prairie, the 
variety of plants and animals present, and its proximity to other 
prairie units. Payments for permanent Prairie Bank easements are based 
on a percentage of the average value of cropland in the township as 
recorded in tax assessment records. To be considered for this program, 
landowners should contact MN DNR's Statewide Acquisition Coordinator, 
one of the MN DNR's three Regional Prairie Specialists. This program 
may benefit the Dakota skipper and Poweshiek skipperling to the extent 
that native prairie that meets the habitat needs of these species is 
protected; parcels protected by the prairie bank program will be 
examined on a case-by-case basis to determine the conservation benefits 
of this program for these two butterfly species.
    At the time of publication of this proposed rule, we have not yet 
identified any specific conservation agreements that would fulfill the 
above criteria, but will work to identify any such agreements and 
conservation partnerships before publication of the final rule. Again, 
however, we are explicitly noting that every type of conservation plan 
and program applicable or available to each proposed unit will be 
considered within the context of whether specific units should be 
excluded from the final critical habitat designation. We encourage any 
non-Federal landowners who are interested in being excluded from a 
final designation to contact us (see ADDRESSES section of this proposed 
rule) to obtain our assistance with crafting and evaluating 
conservation agreements. We are also seeking additional information 
with regard to how designating specific areas as critical habitat would 
affect landowner interest and acceptance of programs that protect 
Dakota skipper or Poweshiek skipperling habitat via conservation 
easements. Continued interest and acceptance of easement programs has 
been identified as one of three factors that are important to the 
conservation of prairie on private lands, in addition to continued 
funding of these programs and other public policy initiatives that 
conserve prairie habitats (Doherty et al. 2013, p. 13).

Peer Review

    In accordance with our joint policy on peer review published in the 
Federal Register on July 1, 1994 (59 FR 34270), we will seek the expert 
opinions of at least three appropriate and independent specialists 
regarding this proposed rule. The purpose of peer review is to ensure 
that our critical habitat designation is based on scientifically sound 
data, assumptions, and analyses. We have invited these peer reviewers 
to comment during this public comment period on our specific 
assumptions and conclusions in this proposed designation of critical 
habitat.
    We will consider all comments and information received during this 
comment period on this proposed rule during our preparation of a final 
determination. Accordingly, the final decision may differ from this 
proposal.

Public Hearings and Informational Meetings

    Section 4(b)(5) of the Act provides for one or more public hearings 
on this proposal, if requested. Requests must be received within 45 
days after the date of publication of this proposed rule in the Federal 
Register. Such requests must be sent to the address shown in FOR 
FURTHER INFORMATION CONTACT. We will schedule public hearings on this 
proposal, if any are requested, and announce the dates, times, and 
places of those hearings, as well as how to obtain reasonable 
accommodations, in the Federal Register and local newspapers at least 
15 days before the hearing.

[[Page 63653]]

    We have scheduled informational meetings regarding the proposed 
rule in the following locations: Minot, North Dakota, on November 5, 
2013, at the Souris Valley Suites, 800 37th Avenue SW.; Milbank, South 
Dakota, on November 6, 2013, at the Milbank Chamber of Commerce, 1001 
East 4th Avenue; Milford, Iowa, on November 7, 2013, at the Iowa 
Lakeside Laboratory, 1838 Highway 86; Holly, Michigan, on November 13, 
2013, at the Rose Pioneer Elementary School, 7110 Milford Road; and, in 
Berlin, Wisconsin, on November 14, 2013, at the Berlin Public Library, 
121 West Park Avenue. Except for the meeting in Berlin, Wisconsin, each 
informational meeting will be from 5:30 p.m. to 8:00 p.m.; the meeting 
in Berlin, Wisconsin will be from 4:30 p.m. to 7:00 p.m.
    Any interested individuals or potentially affected parties seeking 
additional information on the public informational meetings should 
contact the Twin Cities Ecological Services Office (See FOR FURTHER 
INFORMATION CONTACT). The U.S. Fish and Wildlife Service is committed 
to providing access to this event for all participants. Please direct 
all requests for interpreters, closed captioning, or other 
accommodation to the Twin Cities Ecological Services Office (See FOR 
FURTHER INFORMATION CONTACT).

Required Determinations

Regulatory Planning and Review (Executive Order 12866 and 13563)

    Executive Order 12866 provides that the Office of Information and 
Regulatory Affairs (OIRA) in the Office of Management and Budget will 
review all significant rules. The Office of Information and Regulatory 
Affairs has determined that this rule is not significant.
    Executive Order (E.O.) 13563 reaffirms the principles of E.O. 12866 
while calling for improvements in the nation's regulatory system to 
promote predictability, to reduce uncertainty, and to use the best, 
most innovative, and least burdensome tools for achieving regulatory 
ends. The executive order directs agencies to consider regulatory 
approaches that reduce burdens and maintain flexibility and freedom of 
choice for the public where these approaches are relevant, feasible, 
and consistent with regulatory objectives. E.O. 13563 emphasizes 
further that regulations must be based on the best available science 
and that the rulemaking process must allow for public participation and 
an open exchange of ideas. We have developed this rule in a manner 
consistent with these requirements.

Regulatory Flexibility Act (5 U.S.C. 601 et seq.)

    Under the Regulatory Flexibility Act (RFA; 5 U.S.C. 601 et seq.), 
as amended by the Small Business Regulatory Enforcement Fairness Act of 
1996 (SBREFA; 5 U.S.C 801 et seq.), whenever an agency is required to 
publish a notice of rulemaking for any proposed or final rule, it must 
prepare and make available for public comment a regulatory flexibility 
analysis that describes the effects of the rule on small entities 
(small businesses, small organizations, and small government 
jurisdictions). However, no regulatory flexibility analysis is required 
if the head of the agency certifies the rule will not have a 
significant economic impact on a substantial number of small entities. 
The SBREFA amended the RFA to require Federal agencies to provide a 
certification statement of the factual basis for certifying that the 
rule will not have a significant economic impact on a substantial 
number of small entities.
    According to the Small Business Administration, small entities 
include small organizations such as independent nonprofit 
organizations; small governmental jurisdictions, including school 
boards and city and town governments that serve fewer than 50,000 
residents; and small businesses (13 CFR 121.201). Small businesses 
include such businesses as manufacturing and mining concerns with fewer 
than 500 employees, wholesale trade entities with fewer than 100 
employees, retail and service businesses with less than $5 million in 
annual sales, general and heavy construction businesses with less than 
$27.5 million in annual business, special trade contractors doing less 
than $11.5 million in annual business, and forestry and logging 
operations with fewer than 500 employees and annual business less than 
$7 million. To determine whether small entities may be affected, we 
will consider the types of activities that might trigger regulatory 
impacts under this designation as well as types of project 
modifications that may result. In general, the term ``significant 
economic impact'' is meant to apply to a typical small business firm's 
business operations.
    Importantly, the incremental impacts of a rule must be both 
significant and substantial to prevent certification of the rule under 
the RFA and to require the preparation of an initial regulatory 
flexibility analysis. If a substantial number of small entities are 
affected by the proposed critical habitat designation, but the per-
entity economic impact is not significant, the Service may certify. 
Likewise, if the per-entity economic impact is likely to be 
significant, but the number of affected entities is not substantial, 
the Service may also certify.
    Under the RFA, as amended, and following recent court decisions, 
Federal agencies are only required to evaluate the potential 
incremental impacts of rulemaking on those entities directly regulated 
by the rulemaking itself, and not the potential impacts to indirectly 
affected entities. The regulatory mechanism through which critical 
habitat protections are realized is section 7 of the Act, which 
requires Federal agencies, in consultation with the Service, to ensure 
that any action authorized, funded, or carried by the Agency is not 
likely to adversely modify critical habitat. Therefore, only Federal 
action agencies are directly subject to the specific regulatory 
requirement (avoiding destruction and adverse modification) imposed by 
critical habitat designation. Under these circumstances, it is our 
position that only Federal action agencies will be directly regulated 
by this designation. Therefore, because Federal agencies are not small 
entities, the Service may certify that the proposed critical habitat 
rule will not have a significant economic impact on a substantial 
number of small entities.
    We acknowledge, however, that in some cases, third-party proponents 
of the action subject to permitting or funding may participate in a 
section 7 consultation, and thus may be indirectly affected. We believe 
it is good policy to assess these impacts if we have sufficient data 
before us to complete the necessary analysis, whether or not this 
analysis is strictly required by the RFA. While this regulation does 
not directly regulate these entities, in our draft economic analysis we 
will conduct a brief evaluation of the potential number of third 
parties participating in consultations on an annual basis in order to 
ensure a more complete examination of the incremental effects of this 
proposed rule in the context of the RFA.
    In conclusion, we believe that, based on our interpretation of 
directly regulated entities under the RFA and relevant case law, this 
designation of critical habitat will directly regulate only Federal 
agencies, which are not by definition small business entities. And as 
such, we certify that, if promulgated, this designation of critical 
habitat would not have a significant economic impact on a substantial 
number of small business entities. Therefore, an initial

[[Page 63654]]

regulatory flexibility analysis is not required. However, though not 
necessarily required by the RFA, in our draft economic analysis for 
this proposal we will consider and evaluate the potential effects to 
third parties that may be involved with consultations with Federal 
action agencies related to this action.

Energy Supply, Distribution, or Use (Executive Order 13211)

    Executive Order 13211 (Actions Concerning Regulations That 
Significantly Affect Energy Supply, Distribution, or Use) requires 
agencies to prepare Statements of Energy Effects when undertaking 
certain actions. We do not expect the designation of this proposed 
critical habitat to significantly affect energy supplies, distribution, 
or use because the majority of the lands we are proposing do not have 
energy production or distribution. Therefore, this action is not a 
significant energy action, and no Statement of Energy Effects is 
required. However, we will further evaluate this issue as we conduct 
our economic analysis, and review and revise this assessment as 
warranted.

Unfunded Mandates Reform Act (2 U.S.C. 1501 et seq.)

    In accordance with the Unfunded Mandates Reform Act (2 U.S.C. 1501 
et seq.), we make the following findings:
    (1) This rule will not produce a Federal mandate. In general, a 
Federal mandate is a provision in legislation, statute, or regulation 
that would impose an enforceable duty upon State, local, or tribal 
governments, or the private sector, and includes both ``Federal 
intergovernmental mandates'' and ``Federal private sector mandates.'' 
These terms are defined in 2 U.S.C. 658(5)-(7). ``Federal 
intergovernmental mandate'' includes a regulation that ``would impose 
an enforceable duty upon State, local, or tribal governments'' with two 
exceptions. It excludes ``a condition of Federal assistance.'' It also 
excludes ``a duty arising from participation in a voluntary Federal 
program,'' unless the regulation ``relates to a then-existing Federal 
program under which $500,000,000 or more is provided annually to State, 
local, and tribal governments under entitlement authority,'' if the 
provision would ``increase the stringency of conditions of assistance'' 
or ``place caps upon, or otherwise decrease, the Federal Government's 
responsibility to provide funding,'' and the State, local, or tribal 
governments ``lack authority'' to adjust accordingly. At the time of 
enactment, these entitlement programs were: Medicaid; Aid to Families 
with Dependent Children work programs; Child Nutrition; Food Stamps; 
Social Services Block Grants; Vocational Rehabilitation State Grants; 
Foster Care, Adoption Assistance, and Independent Living; Family 
Support Welfare Services; and Child Support Enforcement. ``Federal 
private sector mandate'' includes a regulation that ``would impose an 
enforceable duty upon the private sector, except (i) a condition of 
Federal assistance or (ii) a duty arising from participation in a 
voluntary Federal program.''
    The designation of critical habitat does not impose a legally 
binding duty on non-Federal Government entities or private parties. 
Under the Act, the only regulatory effect is that Federal agencies must 
ensure that their actions do not destroy or adversely modify critical 
habitat under section 7. While non-Federal entities that receive 
Federal funding, assistance, or permits, or that otherwise require 
approval or authorization from a Federal agency for an action, may be 
indirectly impacted by the designation of critical habitat, the legally 
binding duty to avoid destruction or adverse modification of critical 
habitat rests squarely on the Federal agency. Furthermore, to the 
extent that non-Federal entities are indirectly impacted because they 
receive Federal assistance or participate in a voluntary Federal aid 
program, the Unfunded Mandates Reform Act would not apply, nor would 
critical habitat shift the costs of the large entitlement programs 
listed above onto State governments.
    (2) We do not believe that this rule will significantly or uniquely 
affect small governments because the proposed areas that cover small 
government jurisdictions are small, and there is little potential that 
the proposal would impose significant additional costs above those 
associated with the proposed listing of the species. Most lands are 
Federal, State, or privately owned, and most of the units do not occur 
within the jurisdiction of small governments. Therefore, a Small 
Government Agency Plan is not required. However, we will further 
evaluate this issue as we conduct our economic analysis, and review and 
revise this assessment if appropriate.

Takings (Executive Order 12630)

    In accordance with Executive Order 12630 (``Government Actions and 
Interference with Constitutionally Protected Private Property 
Rights''), we have analyzed the potential takings implications of 
designating critical habitat for the Dakota skipper and Poweshiek 
skipperling in a takings implications assessment. Based on the best 
available information, the takings implications assessment concludes 
that this designation of critical habitat for the Dakota skipper and 
Poweshiek skipperling does not pose significant takings implications. 
However, we will further evaluate this issue as we develop our final 
designation, and review and revise this assessment as warranted.

Federalism (Executive Order 13132)

    In accordance with Executive Order 13132 (Federalism), this 
proposed rule does not have significant Federalism effects. A 
Federalism assessment is not required. In keeping with Department of 
the Interior policy, we requested information from, and coordinated 
development of, this proposed critical habitat designation with 
appropriate State resource agencies in Iowa, Michigan, Minnesota, North 
Dakota, South Dakota, and Wisconsin. From a federalism perspective, the 
designation of critical habitat directly affects only the 
responsibilities of Federal agencies. The Act imposes no other duties 
with respect to critical habitat, either for States and local 
governments, or for anyone else. As a result, the rule does not have 
substantial direct effects either on the States, or on the relationship 
between the national government and the States, or on the distribution 
of powers and responsibilities among the various levels of government. 
The designation may have some benefit to these governments because the 
areas that contain the features essential to the conservation of the 
species are more clearly defined, and the physical or biological 
features of the habitat necessary to the conservation of the species 
are specifically identified. This information does not alter where and 
what federally sponsored activities may occur. However, it may assist 
these local governments in long-range planning (because these local 
governments no longer have to wait for case-by-case section 7 
consultations to occur).
    Where State and local governments require approval or authorization 
from a Federal agency for actions that may affect critical habitat, 
consultation under section 7(a)(2) would be required. While non-Federal 
entities that receive Federal funding, assistance, or permits, or that 
otherwise require approval or authorization from a Federal agency for 
an action, may be indirectly impacted by the designation of critical 
habitat, the legally binding duty to avoid destruction or adverse 
modification of critical habitat rests squarely on the Federal agency.

[[Page 63655]]

Civil Justice Reform (Executive Order 12988)

    In accordance with Executive Order 12988 (Civil Justice Reform), 
the Office of the Solicitor has determined that the rule does not 
unduly burden the judicial system and that it meets the requirements of 
sections 3(a) and 3(b)(2) of the Order. We have proposed designating 
critical habitat in accordance with the provisions of the Act. To 
assist the public in understanding the habitat needs of the species, 
the rule identifies the elements of physical or biological features 
essential to the conservation of the species. The designated areas of 
critical habitat are presented on maps, and the rule provides several 
options for the interested public to obtain more detailed location 
information, if desired.

Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et seq.)

    This rule does not contain any new collections of information that 
require approval by OMB under the Paperwork Reduction Act of 1995 (44 
U.S.C. 3501 et seq.). This rule will not impose recordkeeping or 
reporting requirements on State or local governments, individuals, 
businesses, or organizations. An agency may not conduct or sponsor, and 
a person is not required to respond to, a collection of information 
unless it displays a currently valid OMB control number.

National Environmental Policy Act (42 U.S.C. 4321 et seq.)

    We have determined that environmental assessments and environmental 
impact statements, as defined under the authority of the National 
Environmental Policy Act (NEPA; 42 U.S.C. 4321 et seq.), need not be 
prepared in connection with listing a species as endangered or 
threatened under the Endangered Species Act. We published a notice 
outlining our reasons for this determination in the Federal Register on 
October 25, 1983 (48 FR 49244).
    It is our position that, outside the jurisdiction of the U.S. Court 
of Appeals for the Tenth Circuit, we do not need to prepare 
environmental analyses pursuant to NEPA in connection with designating 
critical habitat under the Endangered Species Act. We published a 
notice outlining our reasons for this determination in the Federal 
Register on October 25, 1983 (48 FR 49244). This position was upheld by 
the U.S. Court of Appeals for the Ninth Circuit (Douglas County v. 
Babbitt, 48 F.3d 1495 (9th Cir. 1995), cert. denied 516 U.S. 1042 
(1996)).]

Clarity of the Rule

    We are required by Executive Orders 12866 and 12988 and by the 
Presidential Memorandum of June 1, 1998, to write all rules in plain 
language. This means that each rule we publish must:
    (1) Be logically organized;
    (2) Use the active voice to address readers directly;
    (3) Use clear language rather than jargon;
    (4) Be divided into short sections and sentences; and
    (5) Use lists and tables wherever possible.
    If you feel that we have not met these requirements, send us 
comments by one of the methods listed in the ADDRESSES section. To 
better help us revise the rule, your comments should be as specific as 
possible. For example, you should tell us the numbers of the sections 
or paragraphs that are unclearly written, which sections or sentences 
are too long, the sections where you feel lists or tables would be 
useful, etc.

Government-to-Government Relationship With Tribes

    In accordance with the President's memorandum of April 29, 1994 
(Government-to-Government Relations with Native American Tribal 
Governments; 59 FR 22951), Executive Order 13175 (Consultation and 
Coordination With Indian Tribal Governments), and the Department of the 
Interior's manual at 512 DM 2, we readily acknowledge our 
responsibility to communicate meaningfully with recognized Federal 
Tribes on a government-to-government basis. In accordance with 
Secretarial Order 3206 of June 5, 1997 (American Indian Tribal Rights, 
Federal-Tribal Trust Responsibilities, and the Endangered Species Act), 
we readily acknowledge our responsibilities to work directly with 
tribes in developing programs for healthy ecosystems, to acknowledge 
that tribal lands are not subject to the same controls as Federal 
public lands, to remain sensitive to Indian culture, and to make 
information available to tribes.
    There are tribal lands in North Dakota and South Dakota included in 
this proposed designation of critical habitat. Using the criteria found 
in the Criteria Used to Identify Critical Habitat section, we have 
determined that Tribal lands meet the definition of critical habitat 
for the Dakota skipper and Poweshiek skipperling. We will seek 
government-to-government consultation with these tribes throughout the 
proposal and development of the final designation of critical habitat. 
We will consider these areas for exclusion from final critical habitat 
designation to the extent consistent with the requirements of 4(b)(2) 
of the Act. We informed tribes of how we are evaluating areas under 
section 4(b)(2) of the Act and of our interest in consulting with them 
on a government-to-government basis.

References Cited

    A complete list of references cited in this rulemaking is available 
on the Internet at https://www.regulations.gov and upon request from the 
Twin Cities Ecological Services Field Office (see FOR FURTHER 
INFORMATION CONTACT).

Authors

    The primary authors of this package are staff of the Twin Cities 
Ecological Services Field Office.

List of Subjects in 50 CFR Part 17

    Endangered and threatened species, Exports, Imports, Reporting and 
recordkeeping requirements, Transportation.

Proposed Regulation Promulgation

    Accordingly, we propose to amend part 17, subchapter B of chapter 
I, title 50 of the Code of Federal Regulations, as set forth below:

PART 17--ENDANGERED AND THREATENED WILDLIFE AND PLANTS

0
1. The authority citation for part 17 continues to read as follows:

    Authority: 16 U.S.C. 1361-1407; 1531-1544; and 4201-4245, unless 
otherwise noted.
0
2. In Sec.  17.95, amend paragraph (i) by adding an entry for ``Dakota 
Skipper (Hesperia dacotae)'' after the entry for ``Ash Meadows Naucorid 
(Ambrysus amargosus)'' and an entry for ``Poweshiek Skipperling 
(Oarisma Poweshiek)'' after the entry for ``Laguna Mountains Skipper 
(Pyrgus ruralis lagunae)'', to read as follows:


Sec.  17.95  Critical habitat--fish and wildlife.

* * * * *
    (i) Insects.
* * * * *
Dakota Skipper (Hesperia Dacotae)
    (1) Critical habitat units are designated in Chippewa, Clay, 
Kittison, Lincoln, Murray, Norman, Pipestone, Polk, Pope, and Swift 
Counties in Minnesota; McHenry, McKenzie, Ransom, Richland, Rolette, 
and Wells Counties in North Dakota; and Brookings, Day, Deuel, Grant, 
Marshall, and Roberts Counties in South Dakota.
    (2) Within these areas, the primary constituent elements of the 
physical or

[[Page 63656]]

biological features essential to the conservation of the Dakota skipper 
are:
    (i) Primary Constituent Element 1--Wet-mesic tallgrass or mixed-
grass remnant untilled prairie that occurs on near-shore glacial lake 
soil deposits or high-quality dry-mesic remnant untilled prairie on 
rolling terrain consisting of gravelly glacial moraine soil deposits, 
containing:
    (A) A predominance of native grasses and native flowering forbs,
    (B) Glacial soils that provide the soil surface or near surface 
(between soil surface and 2 cm depth) micro-climate conditions 
conducive to Dakota skipper larval survival and native-prairie 
vegetation such as mean soil surface summer temperatures from 17.8 to 
20.5 [deg]C (64.0 to 68.9 [deg]F), mean near soil surface dew point 
ranging from 13.9 to 16.8 [deg]C (57.0 to 62.2 [deg]F), mean near soil 
surface relative humidity between 72.5 and 85.1 percent, and soil bulk 
densities between 0.86 g/cm\3\ and 1.28 g/cm\3\ (0.5 oz/in\3\ to 0.74 
oz/in\3\);
    (C) If present, trees or large shrub cover of less than 5 percent 
of area in dry prairies and less than 25 percent in wet-mesic prairies; 
and
    (D) If present, nonnative invasive plant species occurring in less 
than 5 percent of area.
    (ii) Primary Constituent Element 2--Native grasses and native 
flowering forbs for larval and adult food and shelter, specifically;
    (A) At least one of the following native grasses to provide food 
and shelter sources during Dakota skipper larval stages: prairie 
dropseed (Sporobolus heterolepis) or little bluestem (Schizachyrium 
scoparium); and
    (B) One or more of the following forbs in bloom to provide nectar 
and water sources during the Dakota skipper flight period: purple 
coneflower (Echinacea angustifolia), bluebell bellflower (Campanula 
rotundifolia), white prairie clover (Dalea candida), upright prairie 
coneflower (Ratibida columnifera), fleabane (Erigeron spp.), 
blanketflower (Gaillardia spp.), black-eyed Susan (Rudbeckia hirta), 
yellow sundrops (Calylophus serrulatus), groundplum milkvetch 
(Astragalus crassicarpus), common gaillardia (Gaillardia aristata), or 
tooth-leaved primrose (Calylophus serrulata).
    (iii) Primary Constituent Element 3--Dispersal grassland habitat 
that is within 1 km (0.6 mi) of native high-quality remnant prairie (as 
defined in Primary Constituent Element 1) that connects high-quality 
wet-mesic to dry tallgrass prairies or moist meadow habitats. Dispersal 
grassland habitat consists of undeveloped open areas dominated by 
perennial grassland with limited or no barriers to dispersal including 
tree or shrub cover less than 25 percent of the area and no row crops 
such as corn, beans, potatoes, or sunflowers.
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, runways, roads, and other paved areas) and the 
land on which they are located existing within the legal boundaries on 
[INSERT EFFECTIVE DATE OF FINAL RULE].
    (4) Critical habitat map units. Data layers defining map units were 
created and digitized using ESRI's ArcMap (version 10.0) and comparing 
USGS NAIP/FSA high-resolution orthophotography from 2010 or later and 
previously mapped skipper habitat polygons submitted by contracted 
researchers or prairie habitat polygons made available from Minnesota 
Department of Natural Resources' County Biological Survey. Critical 
habitat units then were mapped in Geographic Coordinate System WGS84. 
The maps in this entry, as modified by any accompanying regulatory 
text, establish the boundaries of the critical habitat designation. The 
coordinates or plot points or both on which each map is based are 
available to the public at the Service's internet site (https://www.fws.gov/midwest/Endangered), at https://www.regulations.gov at 
Docket No. FWS-R3-ES-2013-0017, and at the field office responsible for 
this designation. You may obtain field office location information by 
contacting one of the Service regional offices, the addresses of which 
are listed at 50 CFR 2.2.

[[Page 63657]]

    (5) Minnesota index map follows:
BILLING CODE 4310-55-P
[GRAPHIC] [TIFF OMITTED] TP24OC13.000


[[Page 63658]]


    (6) North Dakota and South Dakota index map follows:
    [GRAPHIC] [TIFF OMITTED] TP24OC13.001
    

[[Page 63659]]


    (7) DS Minnesota Unit 1, Pope County, Minnesota. Map of DS 
Minnesota Unit 1 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.002


[[Page 63660]]


    (8) DS Minnesota Units 2 and 3, Murray County, Minnesota. Map of DS 
Minnesota Units 2 and 3 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.003


[[Page 63661]]


    (9) DS Minnesota Unit 4, Clay County, Minnesota. Map of DS 
Minnesota Unit 4 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.004


[[Page 63662]]


    (10) DS Minnesota Unit 5, Clay County, Minnesota. Map of DS 
Minnesota Unit 5 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.005


[[Page 63663]]


    (11) DS Minnesota Unit 6, Norman County, Minnesota. Map of DS 
Minnesota Unit 6 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.006


[[Page 63664]]


    (12) DS Minnesota Unit 7, Lincoln County, Minnesota. Map of DS 
Minnesota Unit 7 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.007


[[Page 63665]]


    (13) DS Minnesota Units 8 and 11, Pipestone County, Minnesota. Map 
of DS Minnesota Units 8 and 11 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.008


[[Page 63666]]


    (14) DS Minnesota Unit 9, Pipestone County, Minnesota. Map of DS 
Minnesota Unit 9 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.009


[[Page 63667]]


    (15) DS Minnesota Unit 10, Chippewa County and Swift County, 
Minnesota. Map of DS Minnesota Unit 10 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.010


[[Page 63668]]


    (16) DS Minnesota Unit 12, Lincoln County, Minnesota. Map of DS 
Minnesota Unit 12 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.011


[[Page 63669]]


    (17) DS Minnesota Unit 13, Kittison County, Minnesota. Map of DS 
Minnesota Unit 13 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.012


[[Page 63670]]


    (18) DS Minnesota Units 14 and 15, Polk County, Minnesota. Map of 
DS Minnesota Units 14 and 15 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.013


[[Page 63671]]


    (19) DS North Dakota Unit 1, Richland County, North Dakota. Map of 
DS North Dakota Unit 1 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.014


[[Page 63672]]


    (20) DS North Dakota Units 2 and 13, Ransom County, North Dakota. 
Map of DS North Dakota Units 2 and 13 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.015


[[Page 63673]]


    (21) DS North Dakota Units 3, 4, and 5, McHenry County, North 
Dakota. Map of DS North Dakota Units 3, 4, and 5 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.016


[[Page 63674]]


    (22) DS North Dakota Unit 6, McHenry County, North Dakota. Map of 
DS North Dakota Unit 6 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.017


[[Page 63675]]


    (23) DS North Dakota Units 7 and 8, McHenry County, North Dakota. 
Map of DS North Dakota Units 7 and 8 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.018


[[Page 63676]]


    (24) DS North Dakota Unit 9, Rolette County, North Dakota. Map of 
DS North Dakota Unit 9 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.019


[[Page 63677]]


    (25) DS North Dakota Unit 10, McKenzie County, North Dakota. Map of 
DS North Dakota Unit 10 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.020


[[Page 63678]]


    (26) DS North Dakota Unit 11, McKenzie County, North Dakota. Map of 
DS North Dakota Unit 11 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.021


[[Page 63679]]


    (27) DS North Dakota Unit 12, McKenzie County, North Dakota. Map of 
DS North Dakota Unit 12 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.022


[[Page 63680]]


    (28) DS North Dakota Unit 14, Wells County, North Dakota. Map of DS 
North Dakota Unit 14 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.023


[[Page 63681]]


    (29) DS South Dakota Unit 1, Marshall County, South Dakota. Map of 
DS South Dakota Unit 1 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.024


[[Page 63682]]


    (30) DS South Dakota Unit 2, Brookings County, South Dakota. Map of 
DS South Dakota Unit 2 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.025


[[Page 63683]]


    (31) DS South Dakota Unit 3, Deuel County, South Dakota. Map of DS 
South Dakota Unit 3 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.026


[[Page 63684]]


    (32) DS South Dakota Unit 4, Grant County, South Dakota. Map of DS 
South Dakota Unit 4 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.027


[[Page 63685]]


    (33) DS South Dakota Unit 5, Deuel County, South Dakota. Map of DS 
South Dakota Unit 5 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.028


[[Page 63686]]


    (34) DS South Dakota Unit 6, Roberts County, South Dakota. Map of 
DS South Dakota Unit 6 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.029


[[Page 63687]]


    (35) DS South Dakota Units 7 and 18, Roberts County, South Dakota. 
Map of DS South Dakota Units 7 and 18 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.030


[[Page 63688]]


    (36) DS South Dakota Units 8, 9, 10, and 11, Roberts County, South 
Dakota. Map of DS South Dakota Unit 8, 9, 10, and 11 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.031


[[Page 63689]]


    (37) DS South Dakota Unit 12, 13, 14, and 16, Day County, South 
Dakota. Map of DS South Dakota Unit 12, 13, 14, and 16 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.032


[[Page 63690]]


    (38) DS South Dakota Unit 15, Day County, South Dakota. Map of DS 
South Dakota Unit 15 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.033


[[Page 63691]]


    (39) DS South Dakota Unit 17, Roberts County, South Dakota. Map of 
DS South Dakota Unit 17 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.034


[[Page 63692]]


    (40) DS South Dakota Unit 19, Roberts County, South Dakota. Map of 
DS South Dakota Unit 19 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.035


[[Page 63693]]


    (41) DS South Dakota Units 20, 21, and 22, Brookings County, South 
Dakota. Map of DS South Dakota Units 20, 21, and 22 follows:
[GRAPHIC] [TIFF OMITTED] TP24OC13.036

* * * * *
Poweshiek Skipperling (Oarisma poweshiek)
    (1) Critical habitat units are designated for Cerro Gordo, 
Dickinson, Emmet, Howard, Kossuth, and Osceola Counties in Iowa; in 
Hilsdale, Jackson, Lenawee, Livingston, Oakland, and Washtenaw Counties 
in Michigan; Chippewa, Clay, Cottonwood, Douglas, La Qui Parle, 
Lincoln, Lyon, Mahnomen, Murray, Norman, Pipestone, Pope, Swift, and 
Wilkin Counties in Minnesota; Ransom, Richland, and Sargent Counties in 
North Dakota; Brookings, Day, Deuel, Grant, Marshall, Moody, and 
Roberts Counties in South Dakota; and Green Lake and Waukesha Counties 
in Wisconsin.
    (2) Within these areas, the primary constituent elements of the 
physical or biological features essential to the conservation of 
Poweshiek skipperling consist of four components:
    (i) Primary Constituent Element 1--Wet-mesic to dry tallgrass 
remnant untilled prairies or remnant moist meadows containing:
    (A) A predominance of native grasses and native flowering forbs;
    (B) Undisturbed (untilled) glacial soil types including, but not 
limited to, loam, sandy loam, loamy sand, gravel, organic soils (peat), 
or marl that provide the edaphic features conducive to Poweshiek 
skipperling larval survival and native-prairie vegetation;
    (C) Depressional wetlands or low wet areas, within or adjacent to 
prairies that provide shelter from high summer temperatures and fire;
    (D) If present, trees or large shrub cover less than 5 percent of 
area in dry prairies and less than 25 percent in wet-mesic prairies and 
prairie fens; and
    (E) If present, nonnative invasive plant species occurring in less 
than 5 percent of area.
    (ii) Primary Constituent Element 2--Prairie fen habitats 
containing:
    (A) A predominance of native grasses and native flowering forbs;
    (B) Undisturbed (untilled) glacial soil types including, but not 
limited to, organic soils (peat), or marl that provide the edaphic 
features conducive to Poweshiek skipperling larval survival and native-
prairie vegetation;
    (C) Depressional wetlands or low wet areas, within or adjacent to 
prairies that provide shelter from high summer temperatures and fire;
    (D) Hydraulic features necessary to maintain prairie fen 
groundwater flow and prairie fen plant communities;
    (E) If present, trees or large shrub cover less than 25 percent of 
the unit; and

[[Page 63694]]

    (F) If present, nonnative invasive plant species occurring in less 
than 5 percent of area.
    (iii) Primary Constituent Element 3--Native grasses and native 
flowering forbs for larval and adult food and shelter, specifically:
    (A) At least one of the following native grasses available to 
provide larval food and shelter sources during Poweshiek skipperling 
larval stages: prairie dropseed (Sporobolus heterolepis), little 
bluestem (Schizachyrium scoparium), sideoats grama (Bouteloua 
curtipendula), or mat muhly (Muhlenbergia richardsonis); and
    (B) At least one of the following forbs in bloom to provide nectar 
and water sources during the Poweshiek skipperling flight period: 
purple coneflower (Echinacea angustifolia), black-eyed Susan (Rudbeckia 
hirta), smooth ox-eye (Heliopsis helianthoides), stiff tickseed 
(Coreopsis palmata), palespike lobelia (Lobelia spicata), sticky 
tofieldia (Triantha glutinosa), or shrubby cinquefoil (Dasiphora 
fruticosa ssp. floribunda).
    (iv) Primary Constituent Element 4--Dispersal grassland habitat 
that is within 1 km (0.6 mi) of native high-quality remnant prairie (as 
defined in Primary Constituent Element 1) that connects high-quality 
wet-mesic to dry tallgrass prairies, moist meadows, or prairie fen 
habitats. Dispersal grassland habitat consists of the following 
physical characteristics appropriate for supporting Poweshiek 
skipperling dispersal; undeveloped open areas dominated by perennial 
grassland with limited or no barriers to dispersal including tree or 
shrub cover less than 25 percent of the area and no row crops such as 
corn, beans, potatoes, or sunflowers.
    (3) Critical habitat does not include manmade structures (such as 
buildings, aqueducts, runways, roads, and other paved areas) and the 
land on which they are located existing within the legal boundaries on 
[INSERT EFFECTIVE DATE OF FINAL RULE].
    (4) Critical habitat map units. Data layers defining map units were 
created created and digitized using ESRI's ArcMap (version 10.0) and 
comparing USGS NAIP/FSA high-resolution orthophotography from 2010 or 
later and previously mapped skipper habitat polygons submitted by 
contracted researchers or prairie habitat polygons made available from 
Minnesota Department of Natural Resources' County Biological Survey. 
Critical habitat units then were mapped in Geographic Coordinate System 
WGS84. The maps in this entry, as modified by any accompanying 
regulatory text, establish the boundaries of the critical habitat 
designation. The coordinates or plot points or both on which each map 
is based are available to the public at the Service's internet site 
(https://www.fws.gov/midwest/Endangered/), at https://www.regulations.gov 
at Docket No. FWS-R3-ES-2013-0017, and at the field office responsible 
for this designation. You may obtain field office location information 
by contacting one of the Service regional offices, the addresses of 
which are listed at 50 CFR 2.2.
    (5) Iowa index map follows:

[[Page 63695]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.037

    (6) Michigan index map follows:

[[Page 63696]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.038

    (7) Minnesota index map follows:

[[Page 63697]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.039

    (8) North and South Dakota index map follows:

[[Page 63698]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.040

    (9) Wisconsin index map follows:

[[Page 63699]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.041

    (10) PS Iowa Unit 1, Howard County, Iowa. Map of PS Iowa Unit 1 
follows:

[[Page 63700]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.042

    (11) PS Iowa Unit 2, Cerro Gordo County, Iowa. Map of PS Iowa Unit 
2 follows:

[[Page 63701]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.043

    (12) PS Iowa Units 3, 4, and 7, Dickinson County, Iowa. Map of PS 
Iowa Units 3, 4, and 7 follows:

[[Page 63702]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.044

    (13) PS Iowa Unit 5, Dickinson County, Iowa. Map of PS Iowa Unit 5 
follows:

[[Page 63703]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.045

    (14) PS Iowa Unit 6, Dickinson County, Iowa. Map of PS Iowa Unit 6 
follows:

[[Page 63704]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.046

    (15) PS Iowa Unit 8, Osceola County, Iowa. Map of PS Iowa Unit 8 
follows:

[[Page 63705]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.047

    (16) PS Iowa Unit 9, Dickinson County, Iowa. Map of PS Iowa Unit 9 
follows:

[[Page 63706]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.048

    (17) PS Iowa Unit 10, Kossuth County, Iowa. Map of PS Iowa Unit 10 
follows:

[[Page 63707]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.049

    (18) PS Iowa Unit 11, Emmet County, Iowa. Map of PS Iowa Unit 11 
follows:

[[Page 63708]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.050

    (19) PS Michigan Unit 1, Oakland County, Michigan. Map of PS 
Michigan Unit 1 follows:

[[Page 63709]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.051

    (20) PS Michigan Units 2 and 3, Oakland County, Michigan. Map of PS 
Michigan Units 2 and 3 follows:

[[Page 63710]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.052

    (21) Unit 15: PS Michigan Unit 4, Oakland County, Michigan. Map of 
PS Michigan Unit 4 follows:

[[Page 63711]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.053

    (22) PS Michigan Unit 5, Livingston County, Michigan. Map of PS 
Michigan Unit 5 follows:

[[Page 63712]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.054

    (23) PS Michigan Unit 6, Washtenaw County, Michigan. Map of PS 
Michigan Unit 6 follows:

[[Page 63713]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.055

    (24) PS Michigan Unit 7, Lenawee County, Michigan. Map of PS 
Michigan Unit 7 follows:

[[Page 63714]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.056

    (25) PS Michigan Units 8 and 9, Hillsdale County and Jackson 
County, Michigan. Map of PS Michigan Units 8 and 9 follows:

[[Page 63715]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.057

    (26) PS Minnesota Unit 1, Pope County, Minnesota. Map of PS 
Minnesota Unit 1 follows:

[[Page 63716]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.058

    (27) PS Minnesota Units 2 and 3, Murray County, Minnesota. Map of 
PS Minnesota Units 2 and 3 follows:

[[Page 63717]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.059

    (28) PS Minnesota Units 4 and 18, Clay County, Minnesota. Map of PS 
Minnesota Units 4 and 18 follows:

[[Page 63718]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.060

    (29) PS Minnesota Unit 5, Clay County, Minnesota. Map of PS 
Minnesota Unit 5 follows:

[[Page 63719]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.061

    (30) PS Minnesota Unit 6, Norman County, Minnesota. Map of PS 
Minnesota Unit 6 follows:

[[Page 63720]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.062

    (31) PS Minnesota Unit 7, Lincoln County, Minnesota. Map of PS 
Minnesota Unit 7 follows:

[[Page 63721]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.063

    (32) PS Minnesota Units 8 and 9, Pipestone County, Minnesota. Map 
of PS Minnesota Units 8 and 9 follows:

[[Page 63722]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.064

    (33) PS Minnesota Unit 10, Chippewa County and Swift County, 
Minnesota. Map of PS Minnesota Unit 10 follows:

[[Page 63723]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.065

    (34) PS Minnesota Unit 11, Wilkin County, Minnesota. Map of PS 
Minnesota Unit 11 follows:

[[Page 63724]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.066

    (35) PS Minnesota Unit 12, Lyon County, Minnesota. Map of PS 
Minnesota Unit 12 follows:

[[Page 63725]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.067

    (36) PS Minnesota Unit 13, Lac Qui Parle County, Minnesota. Map of 
PS Minnesota Unit 13 follows:

[[Page 63726]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.068

    (37) PS Minnesota Unit 14, Douglas County, Minnesota. Map of PS 
Minnesota Unit 14 follows:

[[Page 63727]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.069

    (38) PS Minnesota Unit 15, Mahnomen County, Minnesota. Map of PS 
Minnesota Unit 15 follows:

[[Page 63728]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.070

    (39) PS Minnesota Unit 16, Cottonwood County, Minnesota. Map of PS 
Minnesota Unit 16 follows:

[[Page 63729]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.071

    (40) PS Minnesota Unit 17, Pope County, Minnesota. Map of PS 
Minnesota Unit 17 follows:

[[Page 63730]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.072

    (41) PS North Dakota Units 1 and 2, Richland County, North Dakota. 
Map of PS North Dakota Units 1 and 2 follows:

[[Page 63731]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.073

    (42) PS North Dakota Unit 3, Sargent County, North Dakota. Map of 
PS North Dakota Unit 3 follows:

[[Page 63732]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.074

    (43) PS South Dakota Unit 1, Marshall County, South Dakota. Map of 
PS South Dakota Unit 1 follows:

[[Page 63733]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.075

    (44) PS South Dakota Unit 2, Brookings County, South Dakota. Map of 
PS South Dakota Unit 2 follows:

[[Page 63734]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.076

    (45) PS South Dakota Units 3 and 5, Deuel County, South Dakota. Map 
of PS South Dakota Units 3 and 5 follows:

[[Page 63735]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.077

    (46) PS South Dakota Unit 4, Grant County, South Dakota. Map of PS 
South Dakota Unit 4 follows:

[[Page 63736]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.078

    (47) PS South Dakota Unit 6, Roberts County, South Dakota. Map of 
PS South Dakota Unit 6 follows:

[[Page 63737]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.079

    (48) Unit 48: PS South Dakota Unit 7, Roberts County, South Dakota. 
Map of PS South Dakota Unit 7 follows:

[[Page 63738]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.080

    (49) PS South Dakota Units 8, 9, 10, and 11, Roberts County, South 
Dakota. Map of PS South Dakota Units 8, 9, 10, and 11 follows:

[[Page 63739]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.081

    (50) PS South Dakota Unit 12, 13, 14, and 16, Day County, South 
Dakota. Map of PS South Dakota Units 12, 13, 14, and 16 follows:

[[Page 63740]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.082

    (51) PS South Dakota Unit 15, Day County, South Dakota. Map of PS 
South Dakota Unit 15 follows:

[[Page 63741]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.083

    (52) PS South Dakota Unit 17, Moody County, South Dakota. Map of PS 
South Dakota Unit 17 follows:

[[Page 63742]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.084

    (53) PS South Dakota Unit 18, Marshall County and Roberts County, 
South Dakota. Map of PS South Dakota Unit 18 follows:

[[Page 63743]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.085

    (54) PS Wisconsin Unit 1, Waukesha County, Wisconsin. Map of PS 
Wisconsin Unit 1 follows:

[[Page 63744]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.086

    (55) PS Wisconsin Unit 2, Green Lake County, Wisconsin. Map of PS 
Wisconsin Unit 2 follows:

[[Page 63745]]

[GRAPHIC] [TIFF OMITTED] TP24OC13.087

* * * * *

    Dated: September 27, 2013.
Rachel Jacobsen,
Principal Deputy Assistant Secretary for Fish and Wildlife and Parks.
[FR Doc. 2013-24778 Filed 10-23-13; 8:45 am]
BILLING CODE 4310-55-C