Endangered and Threatened Wildlife and Plants; Revised Proposed Designation of Critical Habitat for 12 Species of Picture-Wing Flies From the Hawaiian Islands, 67428-67522 [07-5706]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 72, Number 228 (Wednesday, November 28, 2007)]
[Proposed Rules]
[Pages 67428-67522]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 07-5706]



[[Page 67427]]

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Part III





Department of the Interior





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Fish and Wildlife Service



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50 CFR Part 17



Endangered and Threatened Wildlife and Plants; Revised Proposed 
Designation of Critical Habitat for 12 Species of Picture-Wing Flies 
From the Hawaiian Islands; Proposed Rule

Federal Register / Vol. 72, No. 228 / Wednesday, November 28, 2007 / 
Proposed Rules

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AU93


Endangered and Threatened Wildlife and Plants; Revised Proposed 
Designation of Critical Habitat for 12 Species of Picture-Wing Flies 
From the Hawaiian Islands

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), revise our 
August 15, 2006, proposal to designate critical habitat for 12 species 
of Hawaiian picture-wing flies (Drosophila aglaia, D. differens, D. 
hemipeza, D. heteroneura, D. montgomeryi, D. mulli, D. musaphilia, D. 
neoclavisetae, D. obatai, D. ochrobasis, D. substenoptera, and D. 
tarphytrichia) under the Endangered Species Act of 1973, as amended 
(Act). In total, approximately 9,238 acres (ac) (3,738 hectares (ha)) 
fall within the boundaries of this revised proposed critical habitat 
designation. The revised proposed critical habitat is located in four 
counties (City and County of Honolulu, Hawaii, Maui, and Kauai) in 
Hawaii.

DATES: We will accept comments from all interested parties until 
January 28, 2008. We must receive requests for public hearings, in 
writing, at the address shown in the ADDRESSES section by January 14, 
2008.

ADDRESSES: If you wish to comment on this revised proposed rule, you 
may submit your comments and materials by any one of several methods:
    1. By mail or hand-delivery to: Patrick Leonard, Field Supervisor, 
Pacific Islands Fish and Wildlife Office, U.S. Fish and Wildlife 
Service, 300 Ala Moana Boulevard, Room 3-122, P.O. Box 50088, Honolulu, 
HI 96850.
    2. By electronic mail (e-mail) to: fw1pie_pwfch@fws.gov. Please 
see the Public Comments Solicited section below for other information 
about electronic filing.
    3. By fax to: the attention of Patrick Leonard at 808-792-9581.
    4. Via the Federal eRulemaking Portal at: https://
www.regulations.gov. Follow the instructions for submitting comments.

FOR FURTHER INFORMATION CONTACT: Patrick Leonard, Field Supervisor, 
Pacific Islands Fish and Wildlife Office, 300 Ala Moana Boulevard, Room 
3-122, P.O. Box 50088, Honolulu, HI 96850; telephone 808-792-9400; 
facsimile 808-792-9581. If you use a telecommunications device for the 
deaf (TDD), call the Federal Information Relay Service (FIRS) at 800-
877-8339.

SUPPLEMENTARY INFORMATION:

Public Comments Solicited

    We intend that any final action resulting from this revised 
proposal will be as accurate and as effective as possible. Therefore, 
we request comments or suggestions on this revised proposed rule. We 
particularly seek comments concerning:
    (1) The reasons why we should or should not designate habitat as 
``critical habitat'' under section 4 of the Act, including whether the 
benefit of designation would outweigh threats to the species caused by 
the designation, such that the designation of critical habitat is 
prudent;
    (2) Specific information on:
     The amount and distribution of Drosophila aglaia, D. 
differens, D. hemipeza, D. heteroneura, D. montgomeryi, D. mulli, D. 
musaphilia, D. neoclavisetae, D. obatai, D. ochrobasis, D. 
substenoptera, and D. tarphytrichia habitat,
     What areas occupied at the time of listing and that 
contain the features essential for the conservation of the species we 
should include in the designation and why, and
     What areas not occupied at the time of listing are 
essential to 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) Any foreseeable economic, national security, or other potential 
impacts resulting from the proposed designation and, in particular, any 
impacts on small entities, and the benefits of including or excluding 
areas that exhibit these impacts;
    (5) 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; and
    (6) Our proposed exclusion of 78 acres (ac) (31 hectares (ha)) of 
lands currently managed under the U.S. Army's Oahu Integrated Natural 
Resources Management Plan (INRMP), and whether this INRMP provides a 
benefit to the species and should therefore exempt these lands from 
designation.
    You may submit your comments and materials concerning this revised 
proposal by any one of several methods (see ADDRESSES). If you use e-
mail to submit your comments, please include ``Attn: Hawaii picture-
wing flies critical habitat'' in your e-mail subject header, preferably 
with your name and return address in the body of your message. If you 
do not receive a confirmation from the system that we have received 
your e-mail, contact us directly by calling our Pacific Islands Fish 
and Wildlife Office at 808-792-9400. Please note that we must receive 
comments by the date specified in the DATES section in order to 
consider them in our final determination and that we will close out the 
e-mail address fw1pie_pwfch@fws.gov at the termination of the public 
comment period.
    Before including your address, phone number, e-mail address, or 
other personal identifying information in your comment, you should be 
aware that your entire comment--including your personal identifying 
information--may be made publicly available at any time. While you can 
ask us in your comment to withhold your personal identifying 
information from public review, we cannot guarantee that we will be 
able to do so.
    Comments and materials we receive, as well as supporting 
documentation we used in preparing this revised proposed rule, will be 
available for public inspection, by appointment, during normal business 
hours at the Pacific Islands Fish and Wildlife Office, 300 Ala Moana 
Boulevard, Room 3-122, P.O. Box 50088, Honolulu, HI 96850, (telephone 
808-792-9400).

Background

    It is our intent to discuss only those topics directly relevant to 
the designation of critical habitat in this revised proposed rule. For 
additional information on the 12 species of Hawaiian picture-wing flies 
for which we are proposing to designate critical habitat, refer to the 
final listing rule for the 12 species of picture-wing flies published 
in the Federal Register on May 9, 2006 (71 FR 26835).
    This revised proposal replaces our original proposal to designate 
critical habitat for the 12 species of picture-wing flies published on 
August 15, 2006 (71 FR 46994). In that rule, we proposed to designate 
approximately 18 acres (ac) (7.3 hectares (ha)) as critical habitat for 
11 of the 12 species of Hawaiian picture-wing flies. In that same 
proposal we indicated our intent to exclude several areas from the 
critical habitat designation under section 4(b)(2) of the Act and not 
to include specific areas that we believed did not meet the definition 
of critical habitat under

[[Page 67429]]

section 3(5)(A) of the Act. We did not propose critical habitat for 
Drosophila neoclavisetae, a species endemic to Maui, because we did not 
believe that Maui Pineapple Company's Puu Kukui Watershed Management 
Area met the definition of critical habitat under section 3(5)(A) of 
the Act, based on ongoing conservation efforts. These were the only 
areas identified to be essential for the conservation of D. 
neoclavisetae. Under this revised proposed rule, we are proposing to 
designate critical habitat for D. neoclavisetae. Under this revised 
proposed rule, we are proposing to designate approximately 9,238 ac 
(3,738 ha) as critical habitat for 12 species of Hawaiian picture-wing 
flies. Of these lands, we are exempting 78 ac (31 ha) of land from this 
proposed critical habitat revision under section 4(a)(3)(B)(i) of the 
Act that are covered by the U.S. Army Garrison Hawaii Oahu Training 
Areas Natural Resource Management (Final Report, August 2000) and the 
Oahu Integrated Natural Resource Management Plan 2002-2006 (Army 2000).
    We are revising our original proposal because we received comments 
from peer reviewers in response to the original proposed rule 
questioning the methodology and lack of scientific basis. The current 
revised proposal is based on the best scientific data available, 
including defining suitable habitat based on distribution and density 
of host plants. The methods section of this notice presents the 
specific details and approach used to identify the revised proposed 
critical habitat unit boundaries.

Previous Federal Actions

    For more information on previous Federal actions concerning the 12 
species of Hawaiian picture-wing flies, refer to the final listing rule 
published in the Federal Register on May 9, 2006 (71 FR 26835), and the 
original proposed designation of critical habitat published in the 
Federal Register on August 15, 2006 (71 FR 46994).
    Under the terms of a settlement agreement approved by the U.S. 
District Court for the District of Hawaii on August 31, 2005 (CBD v. 
Allen, CV-05-274-HA), we were to (1) make a final listing decision for 
the 12 picture-wing flies by May 6, 2006; (2) propose to designate 
critical habitat by September 15, 2006; and (3) finalize a critical 
habitat rule by April 17, 2007. Our determination that the designation 
of critical habitat for the 12 species of Hawaiian picture-wing flies 
was prudent was included in the final listing rule, published in the 
Federal Register on May 9, 2006 (71 FR 26849).
    On August 15, 2006, we published a proposal to designate 18 ac (7.3 
ha) of critical habitat for 11 picture-wing fly species on the islands 
of Hawaii, Kauai, Molokai, and Oahu (71 FR 46994). Publication of this 
proposed rule opened a 60-day public comment period, which closed on 
October 16, 2006. On January 4, 2007, we published a notice announcing 
the availability of the draft economic analysis for the designation of 
critical habitat for 11 species of picture-wing flies and reopening the 
public comment period on the proposal until January 19, 2007 (72 FR 
321).
    We received comments from peer reviewers expressing concern with 
the biological adequacy of the proposed 18-acre (7.3-ha) designation, 
and the need to consider host plant density and distribution 
information in determining critical habitat boundaries. In addition, 
one of the peer reviewers presented new observation data for one of the 
species addressed in the proposed rule. On April 16, 2007, we submitted 
a joint stipulation with the Center for Biological Diversity (CBD) to 
the U.S. District Court to modify the timetable of the August 31, 2005, 
settlement agreement for the proposed and final critical habitat rules 
for the 12 Hawaiian picture-wing flies, citing the need to address 
comments received during the public comment periods and to conduct 
additional review of the proposal. A joint stipulation was approved by 
the Court on April 18, 2007, to allow additional time to reconsider the 
proposed rule in light of the comments received, and to provide an 
opportunity for additional public comment. Under the terms of the 
extension, we are required to submit a proposed critical habitat rule 
to the Federal Register by November 15, 2007, and a final critical 
habitat rule by November 15, 2008.

Critical Habitat

    Critical habitat is defined in section 3 of the Act as:
    (1) The specific areas within the geographical area occupied by a 
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) that may require special management considerations or 
protection; and (2) specific areas outside the geographical area 
occupied by a 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 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 under 
the Act are no longer necessary.
    Critical habitat receives protection under section 7 of the Act 
through the prohibition against Federal agencies carrying out, funding, 
or authorizing the destruction or adverse modification of critical 
habitat. Section 7 of the Act requires consultation on Federal actions 
that may affect 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 the landowner.
    For inclusion in a critical habitat designation, habitat within the 
geographical area occupied by the species at the time it was listed 
must first contain features that are essential to the conservation of 
the species. Critical habitat designations identify, to the extent 
known using the best scientific data available, habitat areas that 
provide essential life cycle needs of the species (areas on which are 
found the primary constituent elements, as defined at 50 CFR 
424.12(b)).
    Occupied habitat that contains the features essential to the 
conservation of the species meets the definition of critical habitat 
only if those features may require special management considerations or 
protection.
    Under the Act, we can designate unoccupied areas as critical 
habitat only when we determine that the best available scientific data 
demonstrate that the designation of that area is essential to the 
conservation needs of the species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific and commercial 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

[[Page 67430]]

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 proposed as critical 
habitat, our primary source of information is generally the information 
developed during the listing process for the species. Additional 
information sources 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, or other unpublished materials and expert opinion or 
personal knowledge.
    Habitat is often dynamic, and species may move from one area to 
another over time. Furthermore, we recognize that designation of 
critical habitat may not include all of the habitat areas that may 
eventually be determined to be necessary for the recovery of the 
species, as additional scientific information may become available in 
the future. For these reasons, a critical habitat designation does not 
signal that habitat outside the designated area is unimportant or may 
not be required for recovery of the species.
    Areas that support populations, but are outside the critical 
habitat designation, will continue to be subject to conservation 
actions we implement under section 7(a)(1) of the Act. They are also 
subject to the regulatory protections afforded by the section 7(a)(2) 
jeopardy standard, as determined on the basis of the best available 
scientific information at the time of the agency action. Federally 
funded or permitted projects affecting listed species outside their 
designated critical habitat areas may still result in jeopardy findings 
in some cases. 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 to the extent any new information available to these 
planning efforts calls for a different outcome.

Methods

    As required by section 4(b) of the Act, we used the best scientific 
data available in determining areas occupied at the time of listing 
that contain the features essential to the conservation of Drosophila 
aglaia, D. differens, D. hemipeza, D. heteroneura, D. montgomeryi, D. 
mulli, D. musaphilia, D. neoclavisetae, D. obatai, D. ochrobasis, D. 
substenoptera, and D. tarphytrichia, and areas unoccupied at the time 
of listing that are essential to their conservation. Based on the best 
available information, the units being proposed in this revised 
proposed rule as critical habitat represent the only geographical areas 
known to us that provide these essential conservation features. As a 
result, we are not proposing critical habitat in any areas outside the 
geographical areas presently occupied by each of the 12 species.
    We have also reviewed the available information that pertains to 
the habitat requirements for these species. The following geospatial, 
tabular data sets were used in preparing this revised proposed critical 
habitat: Occurrence data for all 12 species (K. Kaneshiro, in litt. 
2005a, pp. 1-16); vegetation mapping data for the Hawaiian Islands (Gap 
Analysis Program (GAP) Data--Hawaiian Islands 2005); color mosaic 
1:19,000 scale digital aerial photographs for the Hawaiian Islands 
dated April to May 2005; and 1:24,000 scale digital raster graphics of 
U.S. Geological Survey (USGS) topographic quadrangles. Land ownership 
was determined from geospatial data sets associated with parcel data 
from Oahu County (2006); Hawaii County (2005); Kauai County (2005); and 
Maui County (2004).
    We reviewed a variety of peer-reviewed and other articles for this 
revised proposal, which included background information on the biology 
of each of the 12 species, (e.g., Montgomery 1975, pp. 83, 94, 96-98, 
and 100; Foote and Carson 1995, pp. 1-4; Kaneshiro and Kaneshiro 1995, 
pp. 1-47); plant ecology and biology (Wagner et al. 1999, pp. 45, 52-
53, 971, 1,314-1,315, and 1,351-1,352); and the ecology of the Hawaiian 
Islands and the areas being considered in this revised proposal (e.g., 
Smith 1985, pp. 227-233; Stone 1985, pp. 251-253, 256, and 260-263; 
Cuddihy and Stone 1990, pp. 59-66, 73-76, and 88-94). Additional 
information reviewed included the October 29, 1991, final rule listing 
the plant species Urera kaalae (a host plant for two of the fly 
species) as endangered (56 FR 55770); the May 9, 2006, final listing 
rule for the 12 species of picture-wing flies (71 FR 26835); the August 
15, 2006, proposed critical habitat designation for 11 species of 
picture-wing flies (71 FR 46994); unpublished reports by TNCH; and 
aerial photographs and satellite imagery of the Hawaiian Islands.
    We obtained additional information through personal communications 
with landowners, scientists, and land managers familiar with the 12 
species and their habitats, including individuals affiliated with the 
University of Hawaii, University of California at Berkeley, the U.S. 
Geological Survey, the Bishop Museum, Hawaii State Department of Land 
and Natural Resources, TNCH, and the U.S Army. Specific information 
from these sources included estimates of historic and current 
distribution, abundance, and territory sizes for the 12 species, as 
well as data on resources and habitat requirements.
    As described in the final listing rule (May 9, 2006, 71 FR 26835), 
each species of Hawaiian picture-wing fly addressed in this revised 
proposal is found only on a single island, and the larvae of each 
species is dependant upon only a single or a few related species of 
plants (host plant(s)) (summarized in Table 1).

   Table 1.--Distribution of 12 Hawaiian Picture-Wing Flies by Island, General Habitat Type, and Primary Host
                                                    Plant(s)
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                                                                        General habitat
            Species                    Island        Elevation range          type          Primary host plants
----------------------------------------------------------------------------------------------------------------
                                                  Oahu Species
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Drosophila aglaia..............  Oahu.............  1,400-2,900 feet   Mesic forest.....  Urera glabra.
                                                     (ft) (425-885
                                                     meters (m)).
D. hemipeza....................  Oahu.............  1,500-2,900 ft     Mesic forest.....  Cyanea sp., Lobelia
                                                     (460-885 m).                          sp., Urera kaalae
                                                                                           (E).
D. montgomeryi.................  Oahu.............  1,900-2,900 ft     Mesic forest.....  Urera kaalae (E).
                                                     (580-885 m).
D. obatai......................  Oahu.............  1,500-2,500 ft     Dry to mesic       Pleomele forbesii.
                                                     (460-760 m).       forest.

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D. substenoptera...............  Oahu.............  1,300-4,000 ft     Wet forest.......  Cheirodendron
                                                     (395-1,220 m).                        platyphyllum, C.
                                                                                           trigynum,
                                                                                           Tetraplasandra
                                                                                           kavaiensis, T.
                                                                                           oahuensis.
D. tarphytrichia...............  Oahu.............  1,900-2,900 ft     Mesic forest.....  Charpentiera obovata.
                                                     (580-885 m).
----------------------------------------------------------------------------------------------------------------
                                           Hawaii (Big Island) Species
----------------------------------------------------------------------------------------------------------------
D. heteroneura.................  Big Island.......  3,000-6,000 ft     Mesic to wet       Cheirodendron
                                                     (915-1,830 m).     forest.            trigynum, Clermontia
                                                                                           sp., Delissea
                                                                                           parviflora.
D. mulli.......................  Big Island.......  2,150-3,250 ft     Wet forest.......  Pritchardia
                                                     (655-990 m).                          beccariana.
D. ochrobasis..................  Big Island.......  3,400-5,400 ft     Mesic to wet       Clermontia sp.,
                                                     (1,035-1,645 m).   forest.            Marattia douglasii,
                                                                                           Myrsine sp.
----------------------------------------------------------------------------------------------------------------
                                                 Molokai Species
----------------------------------------------------------------------------------------------------------------
D. differens...................  Molokai..........  3,650-4,500 ft     Wet forest.......  Clermontia sp.
                                                     (1,115-1,370 m).
----------------------------------------------------------------------------------------------------------------
                                                  Kauai Species
----------------------------------------------------------------------------------------------------------------
D. musaphilia..................  Kauai............  2,600-3,700 ft     Mesic forest.....  Acacia koa.
                                                     (790-1,130 m).
----------------------------------------------------------------------------------------------------------------
                                                  Maui Species
----------------------------------------------------------------------------------------------------------------
D. neoclavisetae...............  Maui.............  3,400-4,600 ft     Wet forest.......  Cyanea kunthiana, C.
                                                     (1,040-1,400 m).                      macrostegia ssp.,
                                                                                           macrostegia.
----------------------------------------------------------------------------------------------------------------

Oahu Species

Drosophila aglaia

    Drosophila aglaia is historically known from five localities within 
the Waianae Mountains of Oahu between 1,400-2,900 feet (ft) (425-885 
meters (m)) above sea level. Drosophila aglaia is restricted to the 
natural distribution of its larval stage host plant, Urera glabra 
(family Urticaceae), which is a small shrub-like endemic tree found 
within dry to mesic, lowland, Diospyros sp., ohia and koa forest. The 
larvae of D. aglaia feed within the decomposing bark and stem of U. 
glabra. This plant does not form large stands, and is infrequently 
scattered throughout slopes and gulches within mesic forest habitat in 
the Waianae Mountains on Oahu.

Drosophila hemipeza

    Drosophila hemipeza is restricted to the island of Oahu where it is 
historically known from seven localities between 1,500-2,900 ft (460-
885 m) above sea level (not including the Pupukea site, which is 
considered an extirpated population). Montgomery (1975, p. 96) 
determined that D. hemipeza larvae feed within the decomposing portions 
of several different mesic forest plants, including the decomposing 
stems of Lobelia sp. (family Campanulaceae), and the decomposing bark 
and stems of Cyanea sp. (family Campanulaceae), on steep ridges and 
gulches within dry to mesic, lowland, ohia and koa forest (Kaneshiro 
and Kaneshiro 1995, p. 17; Science Panel 2005, p. 16). The larvae also 
feed within the decomposing bark of Urera kaalae (family Urticaceae), a 
federally endangered plant (Service 1995, pp. 81-83; October 29, 1991, 
56 FR 55770) that grows on slopes and in gulches of diverse mesic 
forest (Wagner et al. 1999, pp. 1,314-1,315). In 2004, only 41 
individuals of U. kaalae were known to remain in the wild (USFWS 2004, 
p. 9). In 2005, TNCH outplanted many seedlings of this species at 
several locations within D. hemipeza's historic range (TNCH 2005, p. 
6).

Drosophila montgomeryi

    Drosophila montgomeryi is historically known from three localities 
within the Waianae Mountains on western Oahu between 1,900-2,900 ft 
(580-885 m) above sea level. Montgomery (1975, p. 97) reported that the 
larvae of this species feed within the decaying bark of Urera kaalae, a 
federally endangered plant (USFWS 1995, pp. 81-83; October 29, 1991, 56 
FR 55770) that grows on slopes and in gulches within mesic, lowland, 
diverse ohia and koa forest (Wagner et al. 1999, pp. 1,314-1,315). As 
stated earlier, in 2004, only 41 individuals of U. kaalae were known to 
remain in the wild (USFWS 2004, p. 9). In 2005, TNCH outplanted many 
seedlings of this species at several locations within D. montgomeryi's 
historic range (TNCH 2005, p. 6).

Drosophila obatai

    Drosophila obatai is historically known from two localities between 
1,500-2,500 ft (460-760 m) above sea level on the island of Oahu. 
Drosophila obatai larvae feed within decomposing portions of Pleomele 
forbesii (family Agavaceae), a candidate for Federal listing (May 11, 
2005, 70 FR 24883) (Kaneshiro and Kaneshiro 1995, p. 27; Montgomery 
1975, p. 98). These host plants grow on slopes within dry to mesic, 
lowland, ohia and koa forest, and occur singly or in small clusters, 
rarely forming large stands (Wagner et al. 1999, pp. 1,351-1,352).

Drosophila substenoptera

    Drosophila substenoptera is historically known from seven 
localities in both the Koolau and Waianae Mountains on the island of 
Oahu at elevations between 1,300-4,000 ft (395-1,220 m) above sea 
level. Montgomery (1975, p. 100) determined that D. substenoptera 
larvae feed within the decomposing bark of Cheirodendron platyphllum 
and C. trigynum trees (family Araliaceae), and Tetraplasandra 
kavaiensis and T. oahuensis trees

[[Page 67432]]

(family Araliaceae) in localized patches within mesic to wet, lowland 
to montane, ohia and koa forest.

Drosophila tarphytrichia

    Drosophila tarphytrichia was historically known from both the 
Koolau and the Waianae Mountains between 1,900-2,900 ft (580- to 885 m) 
above sea level on the island of Oahu. Drosophila tarphytrichia is now 
apparently extirpated from the Koolau range, where it was originally 
discovered near Manoa Falls, and is presently known from four 
localities in the Waianae Mountains (Kaneshiro and Kaneshiro 1995; 
Hawaii Biodiversity and Mapping Program (HBMP), in litt. 2005; K. 
Kaneshiro, in litt. 2005a). The larvae of D. tarphytrichia feed on the 
decomposing portions of the stems and branches of Charpentiera obovata 
trees (family Amaranthaceae) within dry to mesic, lowland, ohia and koa 
forest (Montgomery 1975, p. 100).

Hawaii (Big Island) Species

Drosophila heteroneura

    Drosophila heteroneura has been the most intensely studied of the 
12 species discussed in this revised proposed rule (Kaneshiro and 
Kaneshiro 1995, p. 19). This species is restricted to the island of 
Hawaii, where historically it was known to be widely distributed 
between 3,000-6,000 ft (915-1,830 m) above sea level. Drosophila 
heteroneura has been recorded from 24 localities on 4 of the island's 5 
volcanoes (Hualalai, Mauna Kea, Mauna Loa, and Kilauea) within mesic to 
wet, montane, ohia and koa forest (K. Kaneshiro, in litt. 2005a, pp. 4-
8). D. heteroneura larvae primarily feed within the decomposing bark 
and stems of Clermontia sp. (family Campanulaceae), including C. 
clermontioides, and Delissea parviflora (family Campanulaceae), but it 
is also known to feed within decomposing portions of Cheirodendron 
trigynum (family Araliaceae) (Kaneshiro and Kaneshiro 1995, p. 19).

Drosophila mulli

    Drosophila mulli is restricted to the island of Hawaii and is 
historically known from three localities between 2,150-3,250 ft (655-
990 m) above sea level. Only adult flies of these species have ever 
been observed, and only on the leaf undersides of the endemic fan palm, 
Pritchardia beccariana (family Arecaceae), occurring within wet, 
montane, ohia forest. This is the only known association of a 
Drosophila species with a native Hawaiian palm species. The exact 
larval feeding site on this host plant remains unknown because attempts 
to rear D. mulli from decaying parts of P. beccariana have thus far 
been unsuccessful (W. P. Mull, Biologist, pers. comm. 1994, p. 1; 
Science Panel 2005, p. 21).

Drosophila ochrobasis

    Historically, Drosophila ochrobasis was widely distributed between 
3,400-5,400 ft (1,035-1,645 m) above sea level on the island of Hawaii. 
D. ochrobasis has been recorded from 11 localities on 4 of the island's 
5 volcanoes (Hualalai, Mauna Kea, Mauna Loa, and the Kohala mountains) 
(K. Kaneshiro, in litt. 2005a, p. 8; K. Magnacca, University of 
California at Berkley, in litt. 2006). The larvae of this species have 
been reported to feed within decomposing portions of three different 
host plant groups, Myrsine sp. (family Myrsinaceae), Clermontia sp. 
(family Campanulaceae), and Marattia douglasii (family Marattiaceae) 
within mesic to wet, montane, ohia, koa, and Cheirodendron sp. forest 
(Montgomery 1975, p. 98; Kaneshiro and Kaneshiro 1995, p. 29).

Kauai Species

Drosophila musaphilia

    Drosophila musaphilia is historically known from only four sites, 
one at 1,900 ft (579 m) above sea level, and three sites between 2,600-
3,700 ft (790-1,130 m) above sea level on the island of Kauai. 
Montgomery (1975, p. 97) determined that the host plant for D. 
musaphilia is Acacia koa (koa) occurring within mesic, montane, ohia 
and koa forest. The females lay their eggs on, and the larvae develop 
in, the moldy slime flux (seep) that occasionally appears on certain 
trees with injured plant tissue and seeping sap. Understanding the full 
range of D. musaphilia is difficult because its host plant is fairly 
common and stable within and surrounding its known range on Kauai; 
however, the frequency of suitable slime fluxes occurring on the host 
plant appears to be much more restricted and temporally unpredictable 
(Science Panel 2005, pp. 23-24).

Maui Species

Drosophila neoclavisetae

    Two populations of Drosophila neoclavisetae were found historically 
along the Puu Kukui Trail within montane wet Metrosideros polymorpha 
(ohia) forests on West Maui. One habitat site was discovered in 1969 at 
4,500 ft (1,370 m) and the other in 1975 at 3,500 ft (1,070 m) above 
sea level (Kaneshiro and Kaneshiro 1995, p. 26; K. Kaneshiro, in litt. 
2005a, p. 11). The larval stage host plant of D. neoclavisetae has not 
yet been confirmed, although it is likely to be one or both of the two 
Cyanea sp. (Cyanea kunthiana and C. macrostegia ssp. macrostegia) 
(family Campanulaceae) present within its range and occurring within 
wet, montane, ohia forest. Because both collections of this fly 
occurred within a small patch of Cyanea sp., and many other species in 
the Drosophila adiastola species group use plant species in this genus 
and other plants in the family Campanulaceae, researchers believe that 
one or both of the two Cyanea sp. found at Puu Kukui are the correct 
larval stage host plants for D. neoclavisetae (Science Panel 2005, pp. 
19-20; Kaneshiro and Kaneshiro 1995, p. 26).

Molokai Species

Drosophila differens

    Drosophila differens is historically known from three sites between 
3,650-4,500 ft (1,115-1,370 m) above sea level, within montane wet ohia 
forest (K. Kaneshiro, in litt. 2005a, p. 2) on the island of Molokai. 
Montgomery (1975, p. 83) found that D. differens larvae feed within the 
decomposing bark and stems of Clermontia sp. (family Campanulaceae) 
within wet, montane, ohia forest (Kaneshiro and Kaneshiro 1995, p. 16).

Primary Constituent Elements

    In accordance with section 3(5)(A)(i) of the Act and the 
regulations at 50 CFR 424.12, in determining which areas occupied at 
the time of listing to propose as critical habitat, we consider the 
primary constituent elements (PCEs) to be those physical and biological 
features that are essential to the conservation of the species and that 
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 historic geographical and ecological 
distributions of a species.
    We derived the specific primary constituent elements (PCEs) 
required for these 12 picture-wing flies from the biological needs of 
each species as described in the listing rule, published in the Federal 
Register on May 9, 2006 (71 FR 26835), and the August 15, 2006,

[[Page 67433]]

proposed critical habitat designation for 11 picture-wing flies (71 FR 
46994).

Space for Individual and Population Growth and for Normal Behavior

    The general life cycle of Hawaiian Drosophilidae is typical of that 
of most flies: After mating, females lay eggs from which larvae 
(immature stage) hatch; as larvae grow, they molt (shed their skin) 
through three successive stages (instars); and when fully grown, the 
larvae change into pupae (a transitional form) in which they 
metamorphose and emerge as adults.
    Breeding for all 12 species of flies included in this revised 
proposal generally occurs year-round, but egg laying and larval 
development increase following the rainy season as the availability of 
decaying matter, upon which the flies feed, increases in response to 
the heavy rains (K. Kaneshiro, in litt. 2005b, pp. 1-2). In general, 
Drosophila lay between 50 and 200 eggs at a single time. Eggs develop 
into adults in about a month, and adults generally become sexually 
mature one month later. Adults generally live for one to two months.
    It is unknown how much space is needed for these flies to engage in 
courtship and territorial displays, and mating activities. Adult 
behavior may be disrupted or modified by less than ideal conditions, 
such as decreased forest cover or loss of suitable food material (K. 
Kaneshiro, in litt. 2005b, pp. 1-2). Additionally, adult behavior may 
be disrupted and the flies themselves may be susceptible to the hunting 
activities of nonnative hymenoptera including yellow jacket wasps and 
ants (Kaneshiro and Kaneshiro 1995, pp. 41-42). The larvae generally 
pupate within the soil located below their host plant material, and it 
is presumed that they require relatively undisturbed and unmodified 
soil conditions to complete this stage before reaching adulthood 
(Science Panel 2005, p. 5). Lastly, it is well-known that these 12 
species and most picture-wing flies are susceptible to even slight 
temperature increases, an issue that may be exacerbated by loss of 
suitable forest cover or the impacts from global warming (K. Kaneshiro, 
in litt. 2005b, pp. 1-2).

Food

    Each species of Hawaiian picture-wing fly described in this 
document is found only on a single island, and the larvae of each are 
dependent upon only a single or a few related species of plants 
(summarized in Table 1). The adult flies feed on a variety of 
decomposing plant matter. The water or moisture requirements for all 12 
of these species is unknown; however, during drier seasons or during 
times of drought, it is expected that available adult and larval stage 
food material in the form of decaying plant matter may decrease (K. 
Kaneshiro, in litt. 2005b, pp. 1-2).

Primary Constituent Elements for Drosophila aglaia, D. differens, D. 
hemipeza, D. heteroneura, D. montgomeryi, D. mulli, D. musaphilia, D. 
neoclavisetae, D. obatai, D. ochrobasis, D. substenoptera, and D. 
tarphytrichia

    Within the geographical areas occupied by each Drosophila aglaia, 
D. differens, D. hemipeza, D. heteroneura, D. montgomeryi, D. mulli, D. 
musaphilia, D. neoclavisetae, D. obatai, D. ochrobasis, D. 
substenoptera, and D. tarphytrichia, we must identify the PCEs that may 
require special management considerations or protections.
    Based on the requisites for each species discussed above and our 
current knowledge of the life history, biology, and ecology of each 
species, and the requirements to sustain the essential life history 
functions of the 12 species, the following PCEs for larval and adult 
life stages of Drosophila aglaia, D. differens, D. hemipeza, D. 
heteroneura, D. montgomeryi, D. mulli, D. musaphilia, D. neoclavisetae, 
D. obatai, D. ochrobasis, D. substenoptera, and D. tarphytrichia are:

Oahu Species

    The PCEs for Drosophila aglaia are: (1) Dry to mesic, lowland, 
Diospyros sp., ohia and koa forest between the elevations of 1,400-
2,900 ft (425-885 m); and (2) the larval host plant Urera glabra.
    The PCEs for Drosophila hemipeza are: (1) Dry to mesic, lowland, 
ohia and koa forest between the elevations of 1,500-2,900 ft (460-885 
m); and (2) the larval host plants Cyanea angustifolia, C. calycina, C. 
grimesiana ssp. grimesiana, C. grimesiana ssp. obatae, C. membranacea, 
C. pinnatifida, C. superba ssp. superba, Lobelia hypoleuca, L. 
niihauensis, L. yuccoides, and Urera kaalae.
    The PCEs for Drosophila montgomeryi are: (1) Mesic, lowland, 
diverse ohia and koa forest between the elevations of 1,900-2,900 ft 
(580-885 m); and (2) the larval host plant Urera kaalae.
    The PCEs for Drosophila obatai are: (1) Dry to mesic, lowland, ohia 
and koa forest between the elevations of 1,500-2,500 ft (460-760 m); 
and (2) the larval host plant Pleomele forbesii.
    The PCEs for Drosophila substenoptera are: (1) Mesic to wet, 
lowland to montane, ohia and koa forest between the elevations of 
1,300-4,000 ft (395-1,220 m); and (2) the larval host plants 
Cheirodendron platyphyllum ssp. platyphyllum, C. trigynum ssp. 
trigynum, Tetraplasandra kavaiensis, and T. oahuensis.
    The PCEs for Drosophila tarphytrichia are: (1) Dry to mesic, 
lowland, ohia and koa forest between the elevations of 1,900-2,900 ft 
(580-885 m); and (2) the larval host plant Charpentiera obovata.

Hawaii (Big Island) Species

    The PCEs for Drosophila heteroneura are: (1) Mesic to wet, montane, 
ohia and koa forest between the elevations of 3,000-6,000 ft (915-1,830 
m); and (2) the larval host plants Cheirodendron trigynum ssp. 
trigynum, Clermontia clermontioides, C. clermontioides ssp. rockiana, 
C. hawaiiensis, C. kohalae, C. lindseyana, C. montis-loa, C. 
parviflora, C. peleana, C. pyrularia, and Delissea parviflora.
    The PCEs for Drosophila mulli are: (1) Wet, montane, ohia forest 
between the elevations of 3,150-3,250 ft (960-990 m); and (2) the 
larval host plant Pritchardia beccariana.
    The PCEs for Drosophila ochrobasis are: (1) Mesic to wet, montane, 
ohia, koa, and Cheirodendron sp. forest between the elevations of 
3,400-5,400 ft (1,035-1,645 m); and (2) the larval host plants 
Clermontia calophylla, C. clermontioides, C. clermontioides ssp. 
rockiana, C. drepanomorpha, C. hawaiiensis, C. kohalae, C. lindseyana, 
C. montis-loa, C. parviflora, C. peleana, C. pyrularia, C. waimeae, 
Marattia douglasii, Myrsine lanaiensis, M. lessertiana, and M. 
sandwicensis.

Kauai Species

    The PCEs for Drosophila musaphilia are: (1) Mesic, montane, ohia 
and koa forest between the elevations of 2,600-3,700 ft (790-1,130 m); 
and (2) the larval host plant Acacia koa.

Maui Species

    The PCEs for Drosophila neoclavisetae are: (1) Wet, montane, ohia 
forest between the elevations of 3,400-4,600 ft (1,040-1,400 m), and 
(2) the larval host plants Cyanea kunthiana and C. macrostegia ssp. 
macrostegia.

Molokai Species

    The PCEs for Drosophila differens are: (1) Wet, montane, ohia 
forest between the elevations of 3,650-4,500 ft (1,115-1,370 m); and 
(2) the larval host plants Clermontia arborescens ssp. waihiae, C. 
granidiflora ssp. munroi, C. kakeana, C. oblongifolia ssp. brevipes, 
and C. pallida.
    We propose units for designation based on sufficient PCEs being 
present

[[Page 67434]]

to support at least one of each of the 12 species' life history 
functions. Each of the areas proposed in this revised proposed rule 
have been determined to contain sufficient PCEs to provide for both the 
larval and adult life stage for Drosophila aglaia, D. differens, D. 
hemipeza, D. heteroneura, D. montgomeryi, D. mulli, D. musaphilia, D. 
neoclavisetae, D. obatai, D. ochrobasis, D. substenoptera, and D. 
tarphytrichia.

Special Management Considerations or Protections

    When designating critical habitat, we assess whether the occupied 
areas contain features essential to the conservation of the species 
that may require special management considerations or protections.
    Nonnative plants and animals pose the greatest threats to these 12 
picture-wing flies. In order to counter the ongoing degradation and 
loss of habitat caused by feral ungulates and invasive nonnative 
plants, active management or control of nonnative species is necessary 
for the conservation of all populations of the 12 picture-wing flies 
(Kaneshiro and Kaneshiro 1995, pp. 37-38). Without active management or 
control, native habitat containing the features that are essential for 
the conservation of the 12 picture-wing flies will continue to be 
degraded or destroyed. In addition, habitat degradation and destruction 
as a result of fire, competition with nonnative insects, and predation 
by nonnative insects, such as the western yellow-jacket wasp (Vespula 
pensylvanica), may significantly threaten many of the populations of 
the 12 picture-wing flies.
    In this revised proposed rule, all of the proposed critical habitat 
units for the 12 picture-wing flies may require special management to 
address feral ungulates, invasive nonnative plants, and yellow-jacket 
wasps. In addition, the units in dry or mesic habitats (see Table 1 
above) may also require special management to address fire and ants. 
These threats are discussed below.

Feral Ungulates

    Feral ungulates have devastated native vegetation in many areas of 
the Hawaiian Islands (Cuddihy and Stone 1990, pp. 60-66). Because the 
endemic Hawaiian flora evolved without the presence of browsing and 
grazing ungulates, many plant groups have lost their adaptive defenses 
such as spines, thorns, stinging hairs, and defensive chemicals 
(University of Hawaii Department of Geography 1998, p. 138). Pigs (Sus 
scrofa), goats (Capra hircus), and cattle (Bos taurus) disturb the 
soil, and readily eat native plants (including the native host plants 
for 1 or more of the 12 picture-wing flies), and distribute nonnative 
plant seeds that can alter the ecosystem. In addition, browsing and 
grazing by feral ungulates in steep and remote terrain causes severe 
erosion of entire watersheds due to foraging and trampling behaviors 
(Cuddihy and Stone 1990, pp. 60-64 and 66).
Feral Pigs (Sus scrofa)
    Feral pigs threaten all populations of the 12 picture-wing flies. 
Feral pigs are found from dry coastal grasslands through rain forests 
and into the subalpine zone on all of the main Hawaiian Islands 
(Cuddihy and Stone 1990, pp. 64-65). An increase in pig densities and 
expansion of their distribution has caused widespread damage to native 
vegetation (Cuddihy and Stone 1990, pp. 64-65). Feral pigs create open 
areas within forest habitat by digging up, eating, and trampling native 
species (Stone 1985, pp. 262-263). These open areas become fertile 
ground for nonnative plant seeds spread through their excrement and by 
transport in their hair (Stone 1985, pp. 262-263). In nitrogen-poor 
soils, feral pig excrement increases nutrient availability, enhancing 
establishment of nonnative weeds that are more adapted to richer soils 
than are native plants (Cuddihy and Stone 1990, pp. 64-65). In this 
manner, largely nonnative forests replace native forest habitat 
(Cuddihy and Stone 1990, pp. 64-65).
    Foote and Carson (1995, pp. 2-4) found that pig exclosures on the 
island of Hawaii supported significantly higher relative frequencies of 
picture-wing flies compared to other native and nonnative Drosophila 
species (7 percent of all observations outside of the exclosure and 18 
percent of all observations inside the exclosure), and their native 
host plants. Loope et al. (1991, pp. 9-10 and 19) demonstrated that 
excluding pigs from a montane bog on northeastern Haleakala, Maui, 
resulted in an increase in native plant cover from 6 to 95 percent 
after 6 years of protection.
Feral Goats (Capra hircus)
    Feral goats threaten populations of the picture-wing flies on Oahu 
(Drosophila aglaia and D. obatai), Hawaii (D. heteroneura), and Kauai 
(D. musaphilia). Feral goats occupy a wide variety of habitats on 
Kauai, Oahu, Molokai, Maui, and Hawaii, from lowland dry forests to 
montane grasslands where they consume native vegetation, trample roots 
and seedlings, accelerate erosion, and promote invasion of nonnative 
plants (van Riper and van Riper 1982, pp. 34-35; Stone 1985, p. 261). 
On Oahu, goat populations are increasing and spreading in the dry upper 
slopes of the Waianae Mountains, becoming an even greater threat to the 
native habitat (K. Kawelo, U.S. Army Environmental Division, pers. 
comm. 2005, p. 1).
Feral Cattle (Bos taurus)
    Feral cattle threaten populations of Drosophila heteroneura on the 
island of Hawaii. Large-scale ranching of cattle began in the 19th 
century on the islands of Kauai, Oahu, Maui, and Hawaii (Cuddihy and 
Stone 1990, pp. 59-62). Large ranches, tens of thousands of acres in 
size, still exist on the islands of Maui and Hawaii (Cuddihy and Stone 
1990, pp. 59-62). In addition, the grazing of cattle continues in 
several lowland regions in the northern portion of the Waianae 
Mountains of Oahu. Degradation of native forests used for ranching 
activities is evident. Feral cattle occupy a wide variety of habitats 
from lowland dry forests to montane grasslands, where they consume 
native vegetation, trample roots and seedlings, accelerate erosion, and 
promote the invasion of nonnative plants (van Riper and van Riper 1982, 
p. 36; Stone 1985, pp. 256 and 260).

Nonnative Plants

    The invasion of nonnative plants contributes to the degradation of 
native forests and the host plants of picture-wing flies (Kaneshiro and 
Kaneshiro 1995, pp. 38-39; Wagner et al. 1999, pp. 52-53 and 971; 
Science Panel 2005, p. 28), and threatens all populations of the 12 
picture-wing flies. Some nonnative plants form dense stands, thickets, 
or mats that shade or out-compete native plants. Nonnative vines cause 
damage or death to native trees by overloading branches, causing 
breakage, or forming a dense canopy cover that intercepts sunlight and 
shades out native plants below. Nonnative grasses readily burn and 
often grow at the border of forests, and carry fire into areas with 
woody native plants (Smith 1985, pp. 228-229; Cuddihy and Stone 1990, 
pp. 88-94). The nonnative grasses are more fire-adapted and can spread 
prolifically after a fire, ultimately creating a stand of nonnative 
grasses where native forest once existed. Some nonnative plant species 
produce chemicals that inhibit the growth of other plant species (Smith 
1985, p. 228; Wagner et al. 1999, p. 971).

Fire

    Fire threatens habitat of the Hawaiian picture-wing flies in dry to 
mesic grassland, shrubland, and forests on the islands of Kauai 
(Drosophila musaphilia), Oahu (D. aglaia, D.

[[Page 67435]]

hemipeza, D. mongomeryi, D. obatai, and D. tarphytrichia), and Hawaii 
(D. heteroneura). Dry and mesic regions in Hawaii have been altered in 
the past 200 years by an increase in fire frequency, a condition to 
which the native flora is not adapted. The invasion of fire-adapted 
alien plants, facilitated by ungulate disturbance, has contributed to 
wildfire frequency. This change in fire regime has reduced the amount 
of forest cover for native species (Hughes et al. 1991, p. 743; 
Blackmore and Vitousek 2000, p. 625) and resulted in an intensification 
of feral ungulate herbivory in the remaining native forest areas. 
Habitat damaged or destroyed by fire is more likely to be revegetated 
by nonnative plants that cannot be used as host plants by these 
picture-wing flies (Kaneshiro and Kaneshiro 1995, p. 47).

Nonnative Insect Competitors

Tipulid Flies
    The Hawaiian Islands now support several established species of 
nonnative insects which compete with some of the 12 picture-wing flies 
within their larval stage host plants. The most important group of 
nonnative insect competitors includes tipulid flies (crane flies, 
family Tipulidae). The larvae of some species within this group feed 
within the decomposing bark of some of the host plants utilized by 
picture-wing flies, including Charpentiera, Cheirodendron, Clermontia, 
and Pleomele spp. (Science Panel 2005, p. 11; K. Magnacca, U.S. 
Geological Survey, in litt. 2005, p. 1; S. Montgomery, in litt. 2005a, 
p. 1). Therefore, all of the picture-wing flies addressed in this rule, 
except for Drosophila mulli, D. musaphilia, and D. neoclavisetae face 
larval-stage competition from nonnative tipulid flies. The tipulid 
larvae feed within the same portion of the decomposing host plant area 
normally occupied by the picture-wing fly larvae. The likely effect of 
this competition is a reduction in available host plant material for 
picture-wing fly larvae (Science Panel 2005, p. 11). In laboratory 
studies, Grimaldi and Jaenike (1984, p. 1) demonstrated that 
competition between Drosophila spp. larvae and other fly larvae can 
exhaust food resources, which affects both the probability of larval 
survival and the body size of adults, resulting in reduced adult 
fitness, fecundity, and lifespan.
Scolytid Beetles
    Additionally, the Hawaiian Islands now support several species of 
nonnative beetles (family Scolytidae, genus Coccotrypes), a few of 
which bore into and feed on the nuts produced by certain native plant 
species including Pritchardia beccariana, the host plant of Drosophila 
mulli. Affected Pritchardia spp., including P. beccariana, drop their 
fruit before the nuts reach maturity due to the boring action of the 
scolytid beetles. Little natural regeneration of this host plant 
species has been observed in the wild since the arrival of this 
scolytid beetle (K. Magnacca, in litt. 2005, p. 1; Science Panel 2005, 
p. 11). Compared to the host plants of the other picture-wing flies, P. 
beccariana is long lived (up to 100 years), but over time scolytid 
beetles may have a significant impact on the availability of habitat 
for D. mulli.

Nonnative Insect Predators

    Nonnative arthropods pose a serious threat to Hawaii's native 
Drosophila, both through direct predation or parasitism as well as 
competition for food or space (Howarth and Medeiros 1989, pp. 82-83; 
Howarth and Ramsay 1991, pp. 80-83; Kaneshiro and Kaneshiro 1995, pp. 
40-45 and 47; Staples and Cowie 2001, pp. 41, 54-57). Due to their 
large colony sizes and systematic foraging habits, species of social 
Hymenoptera (ants and some wasps) and parasitic wasps pose the greatest 
predation threat to the Hawaiian picture-wing flies (Carson 1982, p. 1, 
1986, p. 7; Gambino et al. 1987, pp. 169-170; Kaneshiro and Kaneshiro 
1995, pp. 40-45 and 47).
Ants
    Ants are believed to threaten populations of picture-wing flies in 
mesic areas on Oahu (Drosophila aglaia, D. hemipeza, D. mongomeryi, D. 
obatai, and D. tarphytrichia) and Hawaii (D. heteroneura) (Kaneshiro 
and Kaneshiro 1995, p. 43; Science Panel 2005, p. 28). At least 44 
species of ants are known to be established on the Hawaiian Islands 
(Hawaii Ecosystems at Risk Project (HEAR) database, in litt. 2005, p. 
2) and 4 particularly aggressive ant species have severely affected the 
native insect fauna (Zimmerman 1948, p. 173; HEAR database, in litt. 
2005, p. 4). Ants are not a natural component of Hawaii's arthropod 
fauna, and native species evolved in the absence of predation pressure 
from ants. Ants can be particularly destructive predators because of 
their high densities, recruitment behavior, aggressiveness, and broad 
range of diet (Reimer 1993, pp. 14-15, 17). The threat to picture-wing 
flies is amplified by the fact that most ant species have winged 
reproductive adults (Borror 1989, pp. 737-738) and can quickly 
establish new colonies, spreading throughout suitable habitats (Staples 
and Cowie 2001, pp. 55-57). These attributes and the lack of native 
species' defenses to ants allow some ant species to destroy isolated 
prey populations (Nafus 1993, p. 151). Hawaiian picture-wing flies 
pupate in the ground where they are exposed to predation by ants. Newly 
emerging adults have been observed with ants attached to their legs 
(Kaneshiro and Kaneshiro 1995, p. 43).
Western Yellow-Jacket Wasp
    An aggressive race of the western yellow-jacket wasp became 
established in the State of Hawaii in 1978, and this species is now 
abundant between 1,969-3,445 ft (600-1,050 m) in elevation (Gambino et 
al. 1990, p. 1,088). On Maui, yellow-jackets have been observed 
carrying and feeding upon recently captured adult Hawaiian Drosophila 
(Kaneshiro and Kaneshiro 1995, p. 41). While there is no documentation 
that conclusively ties the decrease in picture-wing fly observations at 
historical sites with the establishment of yellow-jacket wasps within 
their habitats, the concurrent arrival of wasps and decline of picture-
wing fly observations for all 12 picture-wing flies on several of the 
islands (Kauai, Maui, Molokai, and Hawaii) suggests that the wasps may 
have played a significant role in the decline of some picture-wing fly 
populations (Carson 1982, p. 1, 1986, p. 7; Foote and Carson 1995, p. 
3; Kaneshiro and Kaneshiro 1995; Science Panel 2005, p. 28).

Criteria Used To Identify Critical Habitat

    In this revised proposed rule, we are proposing to designate 
critical habitat on lands with documented occurrences and that contain 
the primary constituent elements for these 12 Hawaiian picture-wing 
flies. The primary dataset we used to document observations of these 12 
picture-wing flies spans the years 1965-1999 (K. Kaneshiro, in litt. 
2005a, pp. 1-16). Additional data were obtained from individuals 
familiar with particular species and locations, and other sources of 
information as described in the above ``Methods'' section. Many sites 
were surveyed infrequently or have not been surveyed for a substantial 
period of time, while other sites have relatively complete records from 
1966-1999. It is important to note that the traditional methods used to 
survey for the 12 species locate only adult flies. The adult flies of 
all of these species are generalist microbivores; in contrast, the 
larval stage typically requires a very specific host plant species (in 
some cases, several species or genera) for successful development. The 
primary constituent elements of the revised proposed critical

[[Page 67436]]

habitat include both the host plants used by the larvae, as well as the 
native forest components used by foraging adults. We used known adult 
location data to identify each critical habitat unit, and included the 
surrounding area encompassing the physical and biological features 
essential to the conservation of the species.
    While there has been considerable survey work conducted for 
Hawaiian picture-wing flies overall, some areas where these 12 species 
are found have not been surveyed in many years. We used the results of 
the best available, recent survey information to develop the revised, 
initial working draft critical habitat unit maps for each species. In 
addition, one peer reviewer identified a population of Drosophila 
ochrobasis that was previously unknown to us in an area containing the 
features essential to the conservation of this species (K. Magnacca, in 
litt. 2006). This area has been included in this revised proposal (see 
Unit 19--West Kohala Mountains--Drosophila ochrobasis).
    We used the best available, recent survey data for adult flies to 
determine which sites we would identify as occupied and which sites we 
would identify as unoccupied. Additionally, we did not include in this 
revised proposal some sites where a given species had been observed 
according to the most recent survey data if the area had either become 
degraded (e.g., due to loss or degradation of native vegetation, 
increase in nonnative vegetation, or documented presence of yellow-
jacket wasps) and lacked PCEs, or if multiple surveys at a particular 
site over the course of several years failed to detect a species. 
However, we did not use the presence of yellow-jacket wasps alone to 
conclusively determine a site as being unoccupied, unless the habitat 
was also degraded in other respects. Lastly, it is important to point 
out that because of the time that has elapsed since some surveys were 
conducted, it is possible that some sites identified as unoccupied (and 
thus not included in this revised proposed critical habitat) have since 
been re-occupied by the species. Conversely, we recognize it may be 
possible that some sites that we have identified as occupied according 
to the most recent survey data may now be unoccupied. However, we 
believe that using the most recent survey results, in conjunction with 
information on existing habitat conditions, reflects the best available 
information for determining occupancy.
    After identifying occupied sites for each of the 12 species on a 
series of maps, we added a Geographic Information System (GIS) layer of 
the known elevation range of a species in a given area. This elevation 
range was based upon the lowest and the highest elevation at which an 
adult fly of a given species was observed during surveys. After this 
step, GIS data points showing known locations of many of the flies' 
host plant species were added to the map series. Most of these plant 
data points were established during botanical surveys unrelated to the 
historic studies of the picture-wing flies. The larval stages for 
several of the 12 picture-wing flies are known to feed upon host plant 
species that are federally listed as endangered or threatened, 
identified as candidate species for listing under the Act, or 
identified as Federal species of concern. The data points for the 
listed and candidate host plant species were available to us from the 
State's Hawaii Biodiversity and Mapping Program (HBMP), and from survey 
information compiled from field biologists. For areas lacking host 
plant data points, we consulted HBMP literature regarding other plant 
species and/or queried Drosophila researchers and field biologists to 
determine which native host plants were present in those areas.
    After generating multilayered GIS maps showing the occupied fly 
population sites, the known elevation range for each species, and the 
known host plant locations or habitat types, we prepared preliminary 
critical habitat unit maps. These preliminary unit maps were then 
overlaid on a series of satellite imagery and aerial photographs, and 
examined closely to identify the best quality areas containing 
contiguous forest and essential features. We then met individually with 
several Drosophila researchers (see the ``Methods'' section above) to 
review the different series of maps for each species and to confirm 
whether the preliminary unit maps included PCEs essential to both life 
stages (larval and adult) of each fly species. Based on these 
discussions, we adjusted the preliminary unit map boundaries by adding 
areas identified by the researchers that contain features essential to 
the conservation of the species, or by removing areas unlikely to 
contain these features. The critical habitat unit boundaries shown in 
the maps included in this revised proposed rule reflect the results of 
this analysis, after taking into account the presence of known 
developed areas, as described below.
    In summary, we identified proposed critical habitat units that: 
Contain occupied population sites based on the most recent survey 
information; are known to contain the PCEs essential to both the larval 
and adult fly life stage for each species; and contain relatively 
contiguous native or functional native forest.
    Lastly, when determining proposed critical habitat boundaries 
within this revised proposed rule, we made ever