Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Astragalus brauntonii and Pentachaeta lyonii, 66374-66423 [06-9089]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 71, Number 219 (Tuesday, November 14, 2006)]
[Rules and Regulations]
[Pages 66374-66423]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 06-9089]



[[Page 66373]]

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Part II





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; Designation of Critical 
Habitat for Astragalus brauntonii and Pentachaeta lyonii; Final Rule

Federal Register / Vol. 71, No. 219 / Tuesday, November 14, 2006 / 
Rules and Regulations

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AU51


Endangered and Threatened Wildlife and Plants; Designation of 
Critical Habitat for Astragalus brauntonii and Pentachaeta lyonii

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), are 
designating critical habitat for the Astragalus brauntonii (Braunton's 
milk-vetch) and Pentachaeta lyonii (Lyon's pentachaeta) pursuant to the 
Endangered Species Act of 1973, as amended (Act). For A. brauntonii, 
approximately 3,300 acres (ac) (1,337 hectares (ha)) fall within the 
boundaries of the critical habitat designation. The critical habitat 
for A. brauntonii is located in Ventura, Los Angeles, and Orange 
Counties, California. For P. lyonii, approximately 3,396 ac (1,372 ha) 
fall within the boundaries of the critical habitat designation. The 
critical habitat for P. lyonii is located in Ventura and Los Angeles 
Counties, California.

DATES: This rule becomes effective on December 14, 2006.

ADDRESSES: Comments and materials received, as well as supporting 
documentation used in the preparation of this final rule, are available 
for public inspection, by appointment, during normal business hours, in 
the branch of Endangered Species, at the Ventura Fish and Wildlife 
Office, 2493 Portola Road, Suite B, Ventura, CA 93003. The final rule, 
economic analysis, and map are also available on the Internet at http:/
/www.fws.gov/ventura.

FOR FURTHER INFORMATION CONTACT: Diane Noda, Field Supervisor, Ventura 
Fish and Wildlife Office, at the address in ADDRESSES (telephone 805/
644-1766; facsimile 805/644-3958). Persons who use a telecommunications 
device for the deaf (TDD) may call the Federal Information Relay 
Service (FIRS) at 800-877-8339, 7 days a week and 24 hours a day.

SUPPLEMENTARY INFORMATION:

Role of Critical Habitat in Actual Practice of Administering and 
Implementing the Act

    Attention to and protection of habitat are paramount to successful 
conservation actions. The role that designation of critical habitat 
plays in protecting habitat of listed species, however, is often 
misunderstood. As discussed in more detail below in the discussion of 
exclusions under section 4(b)(2) of the Act, there are significant 
limitations on the regulatory effect of designation under section 
7(a)(2) of the Act. In brief, (1) designation provides additional 
protection to habitat only where there is a federal nexus; (2) the 
protection is relevant only when, in the absence of designation, 
destruction or adverse modification of the critical habitat would in 
fact take place (in other words, other statutory or regulatory 
protections, policies, or other factors relevant to agency decision-
making would not prevent the destruction or adverse modification); and 
(3) designation of critical habitat triggers the prohibition of 
destruction or adverse modification of that habitat, but it does not 
require specific actions to restore or improve habitat.
    Currently, only 476 species, or 36 percent of the 1,311 listed 
species in the United States under the jurisdiction of the Service, 
have designated critical habitat. We address the habitat needs of all 
1,311 listed species through conservation mechanisms such as listing, 
section 7 consultations, the section 4 recovery planning process, the 
section 9 protective prohibitions of unauthorized take, section 6 
funding to the States, the section 10 incidental take permit process, 
and cooperative, nonregulatory efforts with private landowners. The 
Service believes that it is these measures that may make the difference 
between extinction and survival for many species.
    In considering exclusions of areas originally proposed for 
designation, we evaluated the benefits of designation in light of 
Gifford Pinchot Task Force v. United States Fish and Wildlife Service, 
378 F.3d 1059 (9th Cir 2004) (hereinafter Gifford Pinchot). In that 
case, the Ninth Circuit invalidated the Service's regulation defining 
``destruction or adverse modification of critical habitat.'' In 
response, on December 9, 2004, the Director issued guidance to be 
considered in making section 7 adverse modification determinations. 
This critical habitat designation does not use the invalidated 
regulation in our consideration of the benefits of including areas in 
this final designation. The Service will carefully manage future 
consultations that analyze impacts to designated critical habitat, 
particularly those that appear to be resulting in an adverse 
modification determination. Such consultations will be reviewed by the 
Regional Office prior to finalizing to ensure that an adequate analysis 
has been conducted that is informed by the Director's guidance.
    On the other hand, to the extent that designation of critical 
habitat provides protection, that protection can come at significant 
social and economic cost. In addition, the mere administrative process 
of designation of critical habitat is expensive, time-consuming, and 
controversial. The current statutory framework of critical habitat, 
combined with past judicial interpretations of the statute, make 
critical habitat the subject of excessive litigation. As a result, 
critical habitat designations are driven by litigation and courts 
rather than biology, and made at a time and under a time frame that 
limits our ability to obtain and evaluate the scientific and other 
information required to make the designation most meaningful.
    In light of these circumstances, the Service believes that 
additional agency discretion would allow our focus to return to those 
actions that provide the greatest benefit to the species most in need 
of protection.

Procedural and Resource Difficulties in Designating Critical Habitat

    We have been inundated with lawsuits for our failure to designate 
critical habitat, and we face a growing number of lawsuits challenging 
critical habitat determinations once they are made. These lawsuits have 
subjected the Service to an ever-increasing series of court orders and 
court-approved settlement agreements, compliance with which now 
consumes nearly the entire listing program budget. This leaves the 
Service with little ability to prioritize its activities to direct 
scarce listing resources to the listing program actions with the most 
biologically urgent species conservation needs.
    The consequence of the critical habitat litigation activity is that 
limited listing funds are used to defend active lawsuits, to respond to 
Notices of Intent (NOIs) to sue relative to critical habitat, and to 
comply with the growing number of adverse court orders. As a result, 
listing petition responses, the Service's own proposals to list 
critically imperiled species, and final listing determinations on 
existing proposals are all significantly delayed.
    The accelerated schedules of court-ordered designations have left 
the Service with limited ability to provide for public participation or 
to ensure a defect-free rulemaking process before making decisions on 
listing and critical habitat proposals, due to the risks associated 
with noncompliance with judicially imposed deadlines. This in turn 
fosters a second round of litigation in which those who fear adverse

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impacts from critical habitat designations challenge those 
designations. The cycle of litigation appears endless, and is 
expensive, thus diverting resources from conservation actions that may 
provide relatively more benefit to imperiled species.
    The costs resulting from the designation include legal costs, the 
cost of preparation and publication of the designation, the analysis of 
the economic effects and the cost of requesting and responding to 
public comment, and in some cases the costs of compliance with the 
National Environmental Policy Act (NEPA; U.S.C. 4371 et seq.). These 
costs, which are not required for many other conservation actions, 
directly reduce the funds available for direct and tangible 
conservation actions.

Background

    It is our intent to discuss only those topics directly relevant to 
the designation of critical habitat in this rule. For more information 
on Astragalus brauntonii and Pentachaeta lyonii, refer to the proposed 
critical habitat published in the Federal Register on November 10, 2005 
(70 FR 68982), and the final listing rule published on January 29, 1997 
(62 FR 4172).

Previous Federal Actions

    For more information concerning previous Federal actions concerning 
Astragalus brauntonii and Pentachaeta lyonii, refer to the proposed 
designation of critical habitat published in the Federal Register on 
November 10, 2005 (70 FR 68982). On January 27, 2003, our decision not 
to designate critical habitat for A. brauntonii and P. lyonii was 
challenged in Center for Biological Diversity v. Norton (Case No. 03-
CV-0198-IEG (S.D.Cal.). On July 28, 2003, the Court entered a 
settlement agreement, in which the Service agreed to submit for 
publication a proposal to withdraw the existing ``not prudent'' 
determination together with a new proposed critical habitat 
determination for both species by November 1, 2005. On November 10, 
2005, we published a proposed rule to designate approximately 3,638 ac 
(1,471 ha) of critical habitat in 6 units in Ventura, Los Angeles, and 
Orange Counties, California, for A. brauntonii, and approximately 4,212 
ac (1,703 ha) of critical habitat in 7 units in Ventura and Los Angeles 
Counties, California for P. lyonii (70 FR 68982). On July 21, 2006, we 
published a notice announcing the availability of the draft economic 
analysis (DEA), and reopening of the public comment period (71 FR 
41410). This comment period closed on August 21, 2006.

Summary of Comments and Recommendations

    We requested written comments from the public on the proposed 
designation of critical habitat for Astragalus brauntonii and 
Pentachaeta lyonii in the proposed rule published on November 10, 2005 
(70 FR 68982). We also contacted appropriate Federal, State, and local 
agencies; scientific organizations; and other interested parties and 
invited them to comment on the proposed rule. The initial comment 
period ended January 9, 2006. We published newspaper notices on July 6, 
2006, in the Ventura County Star, Ventura, California; and in the Yorba 
Linda Star, Orange County, California, inviting public comment on the 
economic analysis and proposed critical habitat designation. We did not 
receive any requests for a public hearing.
    During the comment period that opened on November 10, 2005, and 
closed on January 9, 2006, we received 10 comments directly addressing 
the proposed critical habitat designation: 5 from peer reviewers, 1 
from a Federal agency, and 4 from organizations or individuals. During 
the comment period that opened on July 21, 2006, and closed on August 
21, 2006, we received five comments directly addressing the proposed 
critical habitat designation and the draft economic analysis. Of these 
latter comments, one was from a Federal agency, one was from a State 
agency, and three were from organizations or individuals. Fourteen 
commenters supported the designation of critical habitat for Astragalus 
brauntonii and Pentachaeta lyonii, and one commenter did not express 
support or opposition to the designation but requested that the lands 
under their ownership be excluded from the designation of critical 
habitat under section 4(b)(2) of the Act. All comments and new 
information relating to the proposed critical habitat designation for 
A. brauntonii and P. lyonii are addressed in the following summary and 
incorporated into the final rule as appropriate.

Peer Review

    In accordance with our policy published on July 1, 1994 (59 FR 
34270), we solicited expert opinions from seven knowledgeable 
individuals with scientific expertise that included familiarity with 
the species, the geographic region in which the species occurs, and 
conservation biology principles. We received responses from five of the 
peer reviewers. The peer reviewers generally concurred with our methods 
and conclusions and provided additional information, clarifications, 
and suggestions to improve the final critical habitat rule. Peer 
reviewer comments are addressed in the following summary and 
incorporated into the final rule as appropriate.
    We reviewed all comments received from the peer reviewers and the 
public for substantive issues and new information regarding critical 
habitat for Astragalus brauntonii and Pentachaeta lyonii, and address 
them in the following summary.

Peer Reviewer Comments

    1. Comment: A peer reviewer disagreed with our assertion that fire 
suppression was a threat to Astragalus brauntonii and Pentachaeta 
lyonii. He stated that despite efforts to suppress fires in coastal 
southern California, the present frequency of fires, which is every 15 
years or less, is substantially higher than historically, which is 
thought to be every 50 to 100 years. This current fire frequency has 
resulted in displacing native shrubs with non-native grasses that are 
competitively superior to A. brauntonii and P. lyonii. Therefore, he 
recommended that management of critical habitat areas emphasize the 
need for preventing excessive fires.
    Our Response: We agree that excessive fires should be prevented in 
critical habitat areas. We note that Astragalus brauntonii responds 
favorably to fire because it triggers germination of dormant seeds. 
However, if fires are too frequent, this benefit may be outweighed by 
the risk of conversion to non-native grasslands. We recognize that the 
long dormant period for seeds suggests that frequent fires are not 
necessary to ensure persistence, and thus frequent fires should not be 
encouraged. Instead, the management goal should be to maintain those 
conditions to which the species is adapted. Contrary to the reviewer's 
assertion, we did not list fire suppression as a threat to Pentachaeta 
lyonii. Invasion of non-native plants and annual grasses is a major 
threat to both species, and therefore, excessive fires should be 
prevented in critical habitat for both species. We have removed fire 
suppression as a threat to A. brauntonii in the final designation.
    2. Comment: A peer reviewer disagreed with the Service's statement 
that ``critical habitat provides relatively little additional 
protection to listed species,'' because designation of critical habitat 
includes information about the primary constituent elements the species 
needs for persistence and

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recovery. This information can be used by Federal and non-Federal 
agencies to develop a basic landscape scale long-term conservation 
strategy for the species.
    Our Response: The section referenced by the reviewer is intended to 
be a general statement regarding our position on the designation of 
critical habitat. As discussed in the preamble of this and other 
critical habitat designation rules, we believe that, in most cases, 
conservation mechanisms provided through section 7, the section 4 
recovery planning process, the section 9 protective prohibitions of 
unauthorized take, section 6 funding to the States, the section 10 
incidental take permit process, and cooperative programs with private 
and public landowners and Tribes provide greater incentives and 
conservation benefits than does the designation of critical habitat. 
Furthermore, while we agree critical habitat designations include 
species specific information that can be used by Federal and non-
Federal agencies to develop a basic landscape scale long-term 
conservation strategy for a species, agencies may obtain similar types 
of information from other Service documents, such as species recovery 
plans.
    3. Comment: A peer reviewer commented that the proposed critical 
habitat rule did not discuss the Incidental Take permit for Pentachaeta 
lyonii pursuant to Fish and Game Code Section 1081 that is currently 
being processed for the Lake Sherwood Area Plan in Ventura County. The 
peer reviewer stated that most of the western portion of Unit 3c is 
addressed in the plan.
    Our Response: We are aware of the State of California's pending 
Incidental Take permit for the Lake Sherwood Area Plan. However, as of 
this final designation, the plan is not finished and thus has not yet 
been approved. Therefore, we did not consider the potential impacts of 
the proposed activities on Pentachaeta lyonii or critical habitat 
within the Lake Sherwood Area Plan for this designation.
    4. Comment: A peer reviewer stated that we did not include in our 
records a location of Astragalus brauntonii that occurs on the ``old 
Ahmanson property.''
    Our Response: The reviewer is referring to occurrence number 29 in 
the California Natural Diversity Database (CNDDB) record for Astragalus 
brauntonii. The exact location of this occurrence is not known. After 
careful review and inquiries to several individuals who are familiar 
with the occurrences for this species, we have concluded that this 
occurrence is probably incorrect and may not exist. We welcome any 
further information about this occurrence.
    5. Comment: A peer reviewer stated that the ``historic Stunt Ranch 
site'' should be included for recovery purposes for potential 
reintroduction. The reviewer is referring to occurrence number 3 in the 
CNDDB database record for Pentachaeta lyonii.
    Our Response: We did not include this occurrence because it 
currently does not appear to be suitable habitat for Pentachaeta 
lyonii. The species has not been present on the site since it burned in 
1993. The soil in that area has been heavily disturbed by gophers, and 
this has made the area very favorable for non-native annual grasses. 
Despite the fact that this occurrence was not included in critical 
habitat, we recognize that there may be reintroduction potential for 
this site, and would consider this a valid recovery effort for the 
species.
    6. Comment: A peer reviewer thought that the designation of 
critical habitat for Astragalus brauntonii should be postponed until 
the portions of proposed critical habitat that were burned by a 
wildfire in 2005 (subunits 1a-1d and subunits 2a-2f) could be surveyed. 
The fires may have stimulated dormant seeds of A. brauntonii in areas 
where the plant was not known to occur. The purpose of these surveys 
would be to determine if there are additional areas that contain A. 
brauntonii for inclusion into critical habitat.
    Our Response: We were unable to postpone designation of critical 
habitat to wait for the results of post-fire surveys because a July 28, 
2003, settlement agreement and resulting court order mandated that we 
propose critical habitat by November 1, 2005, and finalize the critical 
habitat designation by November 1, 2006. However, we did fund post-fire 
surveys for Astragalus brauntonii in those areas that were burned. The 
results of those surveys revealed several new locations of A. 
brauntonii outside of proposed critical habitat. One location was found 
along a firebreak extending up to 2,297 feet (ft) (700 meters (m)) from 
subunit 2a in Oakbrook Regional Park, and at least four new locations 
were found between subunits 2d and 2e. These locations are within areas 
similar in habitat, and within the known distribution of the species. 
This highlights the difficulty in determining every occurrence of the 
species because the locations of dormant seeds may be unknown until a 
disturbance occurs. However critical habitat does not reflect every 
population or occurrence of A. brauntonii. We are designating habitat 
that we have determined contains the physical and biological features 
essential to the conservation of the species arranged in the quantity 
and spatial characteristics necessary for conservation (see section 
titled ``Critical Habitat'' below for more information on the 
determination of critical habitat).
    7. Comment: A peer reviewer thought that PCE 1 for Astragalus 
brauntonii, which was ``carbonate limestone soils derived from marine 
sediment,'' was not the best description of the soil type associated 
with the plant. A recent study in which soil samples were taken at most 
locations of A. brauntonii revealed that the plant occurs in areas with 
calcium carbonate soils (a broader range of soils), and not necessarily 
where soils are derived from limestone (Landis 2005). The reviewer 
suggested that the original PCE could lead researchers to only look for 
A. brauntonii in soils that are obviously derived from limestone.
    Our Response: We have changed this PCE by removing the reference to 
limestone soils and adding calcium carbonate to the soils description. 
This change is also reflected in ``Areas that Provide the Basic 
Requirements for Growth (Such as Water, Light, and Minerals).''
    8. Comment: A peer reviewer commented that he is aware of 
occurrences of Astragalus brauntonii between Units 3 and 4 but is 
unable to disclose the locations because he entered into a 
``confidentiality clause'' with the clients that commissioned surveys.
    Our Response: We are not entirely surprised that additional 
populations occur in the area between units 3 and 4, because this 
intervening area has similar features and PCEs to the two units. The 
Service has made a diligent effort to gather all sources of information 
concerning the distribution of this species, including surveys and 
other studies, biological assessments, other unpublished materials, and 
the personal knowledge of experts. Our proposed critical habitat was 
based on the best information available to us at the time.
    9. Comment: A peer reviewer wanted to know why there were 
discussions of 4 PCEs for Astragalus brauntonii and Pentachaeta lyonii 
throughout the proposed rule, but only 3 PCEs were listed in the PCE 
section of the proposed rule.
    Our Response: Only three PCEs were included in the proposed rule. 
The reference to 4 PCEs in the proposed rule

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was an error, which has been corrected in this final rule.
    10. Comment: One peer reviewer suggested that a population 
viability analyses would assist us in designing critical habitat units 
that are large enough to assure persistence of sufficiently sized 
populations. Another peer reviewer thought that most of the units are 
too small and should be increased in size to reduce potential impacts 
of Argentine ant invasions on pollinators. Argentine ants are 
associated with manmade structures, and research has shown that they 
reduce native arthropod populations (e.g., bees and wasps) up to 656 ft 
(200 m) from their nests. The peer reviewer commented that Argentine 
ants could threaten the persistence of the plants because they would be 
expected to displace the pollinator community and suggested that we 
should include an additional ``ant buffer'' of 656 ft (200 m) around 
each unit, which would make the minimum unit size about 180 ac (73 ha).
    Our Response: We used the best scientific information available for 
this designation, and the Service does not typically conduct population 
viability analyses to assist in determining critical habitat. We 
acknowledge the potential indirect negative impacts of Argentine ants 
on the pollinators of these plant species and agree that a 656-ft (200-
m) distance from the nearest edge of manmade structure may reduce any 
potential impacts. The impacts of Argentine ants on a rare native plant 
were discussed in a study by Conservation Biology Institute (2000). 
However, critical habitat, within the geographical range occupied by 
the species at the time it was listed, is defined by those physical and 
biological features essential to the conservation of the species (see 
Primary Constituent Elements section) which may require special 
management or protection. Physical and biological features essential to 
the conservation means PCEs arranged in the quantity and spatial 
characteristics necessary for conservation of the species. Critical 
habitat is not intended to create a preserve or other conservation 
area, or to include buffers in order to reduce impacts from manmade 
structures. The potential direct and indirect impacts to critical 
habitat and listed plants as a result of development of manmade 
structures would presumably be addressed through section 7 or other 
regulatory means. Therefore, while we recognize the reviewer's 
position, we believe that any identifiable impacts will be addressed 
through other regulatory means.

Comments From the State

    Section 4(i) of the Act states, ``the Secretary shall submit to the 
State agency a written justification for failure to adopt regulations 
consistent with the agency's comments or petition.'' California 
Department of Fish and Game (CDFG) provided the following comments 
concerning the proposed critical habitat designation for Astragalus 
brauntonii and Pentachaeta lyonii.
    11. Comment: CDFG provided several corrections to our habitat 
description for Pentachaeta lyonii. They stated that P. lyonii is not 
always confined to flat slopes but is known to occur on slopes 20-30 
percent or greater, and said it can occur on thin volcanic surface 
soils underlaid by near-surface volcanic rock, and in localized flat 
areas on steep slopes, dirt hiking trails, and old roadbeds.
    Our Response: We based our habitat description on the best 
available information to us at the time, but acknowledge that 
Pentachaeta lyonii may occur in a broader range of habitat preferences 
than was described in the proposed critical habitat.
    12. Comment: CDFG stated that PCE 2 for Astragalus brauntonii, 
``Low proportion (<10%) of shrub cover directly around the plant,'' was 
not entirely correct because the species may persist in the form of 
dormant seeds within mature stands of chaparral between episodes of 
fire. Therefore, occupied habitat would only contain PCE 2 at some 
points in successional time.
    Our Response: We recognize that Astragalus brauntonii occurrences 
may not contain PCE 2 all of the time, but this PCE is essential for 
the plant to be able to complete a necessary life history component--
seed germination and plant growth. It is not necessary for all three 
PCEs to be present at a site at all times for it to be considered 
critical habitat.
    13. Comment: CDFG said that we were incorrect in stating that 
Pentachaeta lyonii does not maintain a dormant seed bank, and that the 
species responds to favorable growing conditions with dramatic 
increases in population numbers and occupied acreage, suggesting that 
the species maintains some type of seed bank between years.
    Our Response: Keeley (1995) found that seeds buried more that \1/4\ 
inch under the soil for more than 6 months did not germinate, leading 
to his conclusion that the species does not maintain a dormant seed 
bank. However, in a later study, he acknowledged that seeds likely 
remain dormant during drought years (Fotheringham and Keeley 1998), and 
hypothesized that seeds may need to be buried less than \1/4\ inch to 
germinate following long-term dormancy periods. This hypothesis 
contradicted his previous conclusion that the species does not maintain 
a seed bank. We have corrected the final rule to reflect this 
information.
    14. Comment: CDFG employees have observed Pentachaeta lyonii in 
habitat that does not appear to contain a biotic crust, so biotic crust 
should not be considered essential for all populations. In this 
critical habitat designation, PCE 2 is listed as ``Exposed soils that 
exhibit a microbiotic crust which may inhibit invasion by other plant 
competitors.''
    Our Response: Although there has not been a specific study on 
biotic crusts and Pentachaeta lyonii, the habitat of this species was 
characterized in the listing rule by ``a low percentage of total plant 
cover and exposed soils with a microbiotic crust, partially assisting 
with reducing competition with other species.'' Crusts can be seen at 
many occupied sites of P. lyonii, and it is believed that these crusts 
reduce the ability of other plants to invade areas where P. lyonii 
occurs. We believe that this is an important PCE because it highlights 
a special management consideration for this species, which is that 
disturbance of the soil's surface crust should be avoided to prevent 
invasion by other plant species. We recognize that not every occurrence 
may contain microbiotic crusts, and it is not necessary for all three 
PCEs to be present at a site for it to be considered critical habitat.
    15. Comment: CDFG noted that the minimum distance from one edge of 
a proposed unit to the other edge is insufficient to reduce potential 
adverse edge effects. They stated that Argentine ants, which are 
associated with manmade structures, are known to reduce native 
arthropod populations, including known insect pollinators of these 
species, such as bees and wasps. According to research, a distance of 
328-656 ft (100-200 m) from the urban edge to core habitat is needed to 
ensure that core habitats remain free of Argentine ants.
    Our Response: As discussed in our response to comment 10, we 
acknowledge that there is the potential for indirect negative impacts 
of Argentine ants associated with manmade structures on the pollinators 
of these plant species, and agree that an additional 328-656 ft (100-
200 m) distance beyond the proposed units and from the nearest urban 
edge may reduce

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these impacts. However, in defining critical habitat, we believe that 
we have identified those areas that contain the PCEs essential to the 
conservation of the species which may require special management 
considerations or protections. The potential direct and indirect 
impacts to critical habitat and listed plants as a result of 
development of manmade structures would presumably be addressed through 
section 7 or other regulatory means.
    16. Comment: CDFG commented that the true distribution of 
Astragalus brauntonii is not known because of the species' dormant 
seeds that may persist undetected in the soil for many years, and 
recommended using soil and geologic maps to capture additional 
potentially suitable habitat in the vicinity of known locations.
    Our Response: We included additional suitable habitat up to 935 ft 
(285 m) from known occurrences in order to capture areas that are 
likely to contain an undetected seed bank and to allow for genetic 
exchange between patches. We did not include habitat beyond the 935 ft 
(285 m) distance, because those areas are not known to be occupied by 
the species nor do we have evidence to support that this habitat is 
essential to the conservation of the species. We recognize that 
designation of critical habitat may not include all of the habitat 
areas that may ultimately be necessary for the recovery of the species, 
and therefore, critical habitat designations do not signal that habitat 
outside the designation is unimportant or not required for recovery.
    17. Comment: CDFG commented that many of the units for both species 
lack connectivity to other units; suggested connecting units where 
there is potentially suitable geology or soils; and gave specific 
examples of units that could be connected.
    Our Response: We connected occurrences that were within 1,968 ft 
(600 m) of each other into single units to allow for genetic exchange 
between populations. We did not connect occurrences beyond that 
distance because they were not likely to be genetically connected. In 
some cases, units closer than 1,968 ft (600 m) from each other were not 
connected because the intervening habitat was developed and lacked the 
PCEs.

Public Comments on the Process of Designating Critical Habitat

    18. Comment: One commenter stated that the ``historic Stunt Ranch 
site'' should be included for recovery purposes for potential 
reintroduction. This commenter is referring to occurrence number 3 in 
the CNDDB database record for Pentachaeta lyonii.
    Our Response: As explained in our response to peer review comment 
5, we did not include this occurrence because it currently does not 
appear to be suitable habitat for Pentachaeta lyonii. Despite the fact 
that this occurrence was not included in critical habitat, we recognize 
that there may be reintroduction potential for this site, and would 
consider reintroduction to be a valid recovery effort for the species.
    19. Comment: One commenter disagreed with the Service's statement 
that ``critical habitat provides relatively little additional 
protection to listed species'' and asserted that critical habitat 
designations include information about the primary constituent elements 
the species needs for persistence and recovery. This information can be 
used by Federal and non-Federal agencies to develop a basic landscape 
scale long-term conservation strategy for the species.
    Our Response: As discussed in our response to peer review comment 
2, the section referenced by the commenter is intended to be a general 
statement regarding our position on the designation of critical 
habitat. Although it is our position that the conservation and recovery 
of listed species are better served through other conservation 
mechanisms, we agree with the commenter's assertion that the 
information contained in this designation can be used to develop long-
term conservation strategies for the species.
    20. Comment: Several commenters thought that many of the units for 
both species were too small for a variety of reasons. They commented 
that we failed to account for areas needed for pollinator reproduction, 
which are different from pollinator foraging areas and may require 
larger patch sizes to support the pollinator population. One commenter 
asserted that additional area is needed to provide for pollinator 
persistence and pollinator linkages between populations of Pentachaeta 
lyonii, and that the minimum size needed to ensure persistence depends 
on local habitat conditions and the degree of isolation between patch 
sizes. The commenter noted that P. lyonii requires a low proportion of 
vegetative cover to persist, suggesting that patches should be larger 
to contain enough flowering plants to support pollinators. Similarly, a 
commenter thought critical habitat should be enlarged and merged to 
include appropriate soils and potential habitat and provide 
opportunities for pollinator dispersal. In the opinion of the 
commenter, this would provide corridors of connectivity, reducing 
habitat fragmentation and genetic isolation. Larger areas would also 
better support populations that shift in time and space, allow for 
ecosystem processes (including fire or fire-like disturbances) to 
function at appropriate scales, and minimize edge effects.
    Our Response: We generally agree with the conservation biology 
principles and rationale presented by the commenters. However, the Act 
states that critical habitat is ``the specific areas within the 
geographical area occupied by the species * * * on which are found 
those physical or biological features essential to the conservation of 
the species'' (i.e., PCEs (see Primary Constituent Elements section)). 
Furthermore, based on the Act, we only designate critical habitat in 
areas outside the geographical area occupied by the species at the time 
of listing when the best available information indicates that it is 
essential to the conservation of the species.
    We used the best scientific information available to determine the 
necessary habitat to ensure persistence of individual populations. In 
order to reduce fragmentation and preserve genetic connectivity, we 
connected populations within 1,968 ft (600 m) of each other because 
they are likely to be visited by the same pollinators. We also 
designated suitable habitat to allow for important life-history 
functions such as seed dispersal and presence of pollinators, and 
included areas that likely contain a seed bank and/or unmapped patches 
within populations. We believe that our critical habitat design 
captures the areas essential to the conservation to the species based 
on the best scientific information currently available. We believe that 
by capturing entire populations within single critical habitat units 
and by connecting populations within 1,968 ft (600 m) of each other 
into single units, the species will persist and pollination will 
continue.
    21. Comment: One commenter thought that surveys should be conducted 
for Astragalus brauntonii and Pentachaeta lyonii because of a wildfire 
that burned areas within the known distribution of the species, and any 
additional locations discovered should be included in critical habitat.
    Our Response: As discussed in our response to comment 6, we were 
unable to postpone our proposed designation of critical habitat further 
to incorporate the results of these surveys, although we funded post-
fire surveys for Astragalus brauntonii in those areas that were burned 
and found additional locations

[[Page 66379]]

of the species. We determined that the fire did not burn within the 
known distribution of Pentachaeta lyonii, so there was no need for 
post-fire surveys.
    22. Comment: One commenter thought that PCE 1 for Astragalus 
brauntonii, ``carbonate limestone soils derived from marine sediment,'' 
was not the best description of the soil type associated with the 
plant. A recent study in which soil samples were taken at locations of 
A. brauntonii revealed that the plant occurs with calcium carbonate 
soils (a broader range of soils), and not necessarily with limestone-
derived soils (Landis 2005). The PCE as originally proposed could lead 
researchers to only look for A. brauntonii on soils that are obviously 
derived from limestone.
    Our Response: As stated in our response to comment 7, we have 
changed this PCE by removing the reference to limestone soils and 
adding calcium carbonate to the soils description. This change is also 
reflected in ``Areas that Provide the Basic Requirements for Growth 
(Such as Water, Light, and Minerals)''.
    23. Comment: Two commenters thought that an occurrence of 
Astragalus brauntonii located within the City of Oak Park should have 
been included within critical habitat because it contains the largest 
known seed bank in the Simi Hills. The commenters noted that inclusion 
of this occurrence, if a 3,281-ft (1,000-m) zone to protect pollinator 
habitat was incorporated, would link units 2c and 2d. In addition, one 
of the commenters stated that a ``Rare Plant Conservation Plan'' is in 
effect in the Oak Park area that covers three tiny preserves within 
open space and a ``demonstration garden'' that contains A. brauntonii, 
on land owned and managed by the Rancho Simi Recreation and Parks 
District. The commenter states that the plan does not adequately ensure 
the conservation and persistence of A. brauntonii, and should not be 
used as a basis to exclude this occurrence from critical habitat.
    Our Response: The commenters are referring to occurrence 20 in the 
CNDDB record for Astragalus brauntonii. We did not include this 
occurrence because it does not contain the PCEs. A large portion of 
this occurrence was removed by Rancho Simi Recreation and Parks 
District to create a city park, other portions were removed by urban 
development, and very small remaining portions are surrounded by or 
directly adjacent to urban development. It is difficult to determine 
the size of a seed bank, and there is no clear evidence that this 
occurrence contains the largest known seed bank in the Simi Hills, 
although small numbers of plants and a seed bank may remain within open 
space areas along the periphery of developed areas. Remaining portions 
of this occurrence are almost completely surrounded by urban 
development; therefore, we would be unable to link units 2c and 2d 
because we do not intentionally include developed areas such as 
buildings, paved areas, and other areas that lack the PCEs. Because 
this occurrence does not contain the PCEs, we did not evaluate the 
existing conservation plan as a basis for excluding this occurrence 
from critical habitat.
    24. Comment: Several commenters identified portions of Pentachaeta 
lyonii populations that were not included in the designation (e.g., in 
subunit 2a, and Unit 4), and also thought that intervening habitat 
between subunits should have been included (e.g., between subunits 2b 
and 2c, and between the two parts of subunit 3c).
    Our Response: We do not intentionally include developed areas such 
as buildings, paved areas, and other areas that lack the PCEs in our 
critical habitat designations. Based on aerial photos of those areas 
(PhotoMapper 3.50, AirPhoto USA, NW Los Angeles Map 1999), we 
determined that those portions of populations and intervening habitat 
were previously removed by urban development.
    25. Comment: A commenter thought we should have included 
Pentachaeta lyonii occurrences 9 and 19 from the CNDDB records in 
critical habitat.
    Our Response: We only included extant occurrences that contain the 
PCEs within critical habitat. We did not include occurrence 9 within 
the nearby Unit 7 (Malibu Lake unit) because, based on the CNDDB 
records, this occurrence has been extirpated since 1992. We did not 
include occurrence 19 because three of the four patches of Pentachaeta 
lyonii within this occurrence were removed by construction of a golf 
course. The fourth and only remaining patch is within approximately a 
500 square-foot (46-square-meter) area, and is surrounded by the golf 
course. We believe that this remaining occurrence contains a population 
size of fewer than 10 individuals and may have even been extirpated. 
This location lacks the PCEs and has little recovery or conservation 
value; therefore, it was not included in the critical habitat 
designation.
    26. Comment: There were several suggestions of simple management 
strategies for protecting both species that would not result in 
economic hardship on any jurisdiction or management agency, as well as 
suggestions for additional new criteria for delisting. For Astragalus 
brauntonii, suggested management techniques include: Lifting the blade 
of bulldozers at least 18 inches in the air when clearing roads or 
creating firebreaks; using weed-whackers to clear weeds around the 
plant; and leaving cut stalks and seedpods on the side of the road 
rather than removing A. brauntonii plant material. For Pentachaeta 
lyonii, suggested management techniques include routing roads around 
critical habitat areas and controlling non-native weeds invading 
critical habitat areas without the use of herbicides and without 
disturbing the soil. For both species, suggested management techniques 
include not transplanting plants as a conservation tool because both 
species are dependent on specific soil characteristics and performing 
road maintenance, fuel modification, and other management activities 
after fruiting.
    Our Response: We have incorporated some of the management 
strategies into the section titled ``Special Management Considerations 
or Protections'' in this rule. We may also provide these suggestions, 
in the form of best management practices, to local agencies when we 
provide technical assistance regarding ways to reduce impacts to listed 
species, and to Federal agencies through the section 7 consultation 
process. The suggested new criteria for delisting are valid recovery 
actions that we may attempt to accomplish in future recovery actions 
for the species. These criteria may also be incorporated into a revised 
recovery plan at some point in the future.
    27. Comment: One commenter thought that the proposed critical 
habitat only maintains both species at their current level with no 
opportunity for recovery because we do not propose unoccupied suitable 
habitat. Other commenters thought that we should have included 
unoccupied suitable habitat on land owned by the National Park Service 
(NPS) or by local open space agencies because they represent 
opportunities for population expansion for the species. They noted that 
an experimental population of Pentachaeta lyonii was recently 
introduced at Paramount Ranch on NPS land, illustrating the potential 
for reintroductions into other areas.
    Our Response: We disagree with the commenter that our proposal and 
designation do not provide opportunities for recovery of the species. 
Our critical habitat designation noted the fact that both plants occur 
in patchy distributions both physically and temporally. In order to 
incorporate

[[Page 66380]]

entire populations, we conducted a nearest neighbor analysis and 
determined that the average distance between patches of plants was 275 
m (902 ft) for Pentachaeta lyonii and 285 m (935 ft) for Astragalus 
brauntonii. Therefore, in areas where the habitat was contiguous and 
PCEs were present, we included suitable habitat up to 275 m (902 ft) 
and 285 m (935 ft) from known patches of P. lyonii and A. brauntonii, 
respectively, to ensure that we captured the entire population 
(including the seed bank) within one critical habitat unit and 
minimized fragmentation. Furthermore, where we had populations within 
600 m (1,968 ft) of one another and the habitat was contiguous and 
contained the PCEs, we connected those populations together in one unit 
to facilitate genetic exchange between populations through pollinator 
activity. We expect that these areas contain a seed bank, and/or 
additional suitable habitat for population expansion through seed 
dispersal. Both of these strategies capture recovery opportunities for 
the species and, through these strategies, we believe we have captured 
the entire area necessary to ensure persistence of the species. For 
further information, please refer to the ``Criteria Used to Identify 
Critical Habitat'' section. Although we did not designate specific 
areas of unoccupied habitat for potential reintroductions, we believe 
that this can be an important recovery tool for P. lyonii, particularly 
on Federal Lands, and we support these types of actions. We recognize 
that designation of critical habitat may not include all of the habitat 
areas that are necessary for the recovery of the species, and 
therefore, critical habitat designations do not signal that habitat 
outside the designation is unimportant or not required for recovery.
    28. Comment: A researcher commented that we were incorrect in 
stating that Pentachaeta lyonii does not maintain a dormant seed bank. 
Surveys conducted in multiple years at the same site show large 
fluctuations in population size, and this would likely be impossible 
unless the species maintains a seed bank for at least 5 to 10 years.
    Our Response: As discussed in our response to comment 13 from the 
State, we have corrected the final rule to reflect this information.
    29. Comment: A researcher commented that the role of biotic crusts 
is unsupported by data and that this should not be used for PCE 2 for 
Pentachaeta lyonii because it suggests that crust is a required element 
for P. lyonii habitat. In the proposed designation, PCE 2 was listed as 
``Exposed soils that exhibit a microbiotic crust which may inhibit 
invasion by other plant competitors.''
    Our Response: As discussed in our response to comment 14, we 
recognize that not every occurrence may contain microbiotic crusts, and 
it is not necessary for all three PCEs to be present at a site for it 
to be considered critical habitat.
    30. Comment: A researcher commented that PCE 3 for Pentachaeta 
lyonii should focus on the presence of bare ground rather than on 
proportion of vegetative cover. In the proposed designation, PCE 3 was 
listed as ``low proportion of total vegetative cover (<25%).'' The 
commenter asserted that this PCE can be misleading because, based on 
research, P. lyonii is found in areas with 20 to 60 percent cover of 
native vegetation at a larger scale (i.e., 538 to 2,153 square foot 
patch sizes (50 to 200 square meter)). Although the species can be 
found in areas with a larger proportion of total vegetative cover, 
there needs to be small openings of bare ground for the plant to grow 
in (i.e., > 10% bare ground on a small scale of less than approximately 
3 ft (1 m) because it does not compete well with other species. In 
addition, the researcher found that plant litter accumulation 
associated with annual grass invasion reduces P. lyonii populations. 
The commenter indicated that this finding further highlights that bare 
ground is an essential component of this species' habitat.
    Our Response: We agree with the researcher's comment, and have 
changed P. lyonii PCE 3 to read: ``a mosaic of bare ground (>10%) 
patches in an area with less than 60 percent cover.'' We believe this 
more accurately reflects the physical and biological needs essential to 
the conservation of the species.
    31. Comment: A researcher commented that we should have a PCE that 
addresses habitat quality based on presence of Pentachaeta lyonii-
associated native plant species and the absence of non-native invasive 
plants. P. lyonii habitat that is in decline shows increased presence 
of non-native species, build-up of litter cover and loss of bare 
ground, and slow loss of associated species.
    Our Response: We agree that presence of non-native invasive plants 
indicates poor habitat quality for Pentachaeta lyonii, and that 
presence of some associated native species can be a good indicator of 
good habitat quality, and this concept was discussed in the proposed 
and final rule. However, we believe that PCEs 2 and 3 adequately 
capture habitat quality, because it is unlikely that either PCE would 
exist if the unit became overtaken with non-native invasive plants.

Comments Related to the Draft Economic Analysis

    32. Comment: Two commenters stated that economic analysis 
overestimates the cost of critical habitat designation because it will 
affect real estate development on private lands only where there is a 
Federal nexus. Such a nexus will not exist for most projects in the 
area proposed as critical habitat.
    Our Response: We recognize that real estate development on private 
lands does not come under the purview of the section 7 consultation 
process unless there is a Federal nexus. However, it is difficult to 
predict which future actions may bare a Federal nexus. The methodology 
of the analysis quantifies future costs when it is possible to isolate 
and measure them and then calculates the economic surplus resulting 
from future activities that may take place within proposed critical 
habitat. This approach avoids speculation about regulatory impacts. It 
is, however, possible to calculate the value added from development 
activities within areas of critical habitat. By using this methodology, 
we believe we have appropriately captured potential costs to the real 
estate development sector.
    33. Comment: One commenter stated that costs that occurred prior to 
designation should not be included in the cost of critical habitat 
designation.
    Our Response: Based on the 10th Circuit Court's ruling in New 
Mexico Cattle Growers Association v. U.S. Fish and Wildlife Service, 
248 F.3d 1277, 128 (10th Cir. 2001) the Service conducts a full 
analysis of all the economic impacts of a critical habitat designation, 
regardless of whether those impacts are attributable co-extensively to 
other causes. Accordingly, here, the economic analysis specifies that 
it considers the future economic impacts associated with critical 
habitat designation and past costs that have resulted from efforts to 
conserve the species within areas of critical habitat. As explained in 
section III.1, past costs are defined as costs that occurred between 
when the species was listed under the Endangered Species Act and the 
present. These past costs are not attributable to critical habitat.
    34. Comment: One commenter suggested that past development projects 
in areas of critical habitat should be analyzed to determine the 
limitations on development arising from critical habitat.
    Our Response: The economic analysis uses consultation history to 
determine how many future development projects

[[Page 66381]]

will have a Federal nexus and what the recommended restriction on 
development will be. For both species in question, the number of 
available consultations on private development projects is highly 
limited or nonexistent. The available evidence, however, suggests that 
total avoidance of the species has been required in the past; for 
example, the 1999 consultation with Lennar Homes referenced in the 
report.
    35. Comment: One commenter stated that that local zoning and other 
restrictions limit the pace of development, thus reducing the costs of 
critical habitat.
    Our Response: We agree that local regulation plays a large role in 
determining the timing and intensity of development. The development 
projections from the Southern California Association of Governments 
(SCAG) that form the basis of the economic modeling incorporate these 
restrictions.
    36. Comment: One commenter stated that there are many additional 
benefits of critical habitat designation beyond just the conservation 
of habitat for the listed species, and that these should be included in 
the economic analysis.
    Our Response: In the context of a critical habitat designation, the 
primary purpose of the rulemaking (i.e., the direct benefit) is to 
designate areas in need of special management that contain the features 
that are essential to the conservation of listed species.
    The designation of critical habitat may result in two distinct 
categories of benefits to society: (1) Use; and (2) non-use benefits. 
Use benefits are simply the social benefits that accrue from the 
physical use of a resource. Visiting critical habitat to see endangered 
species in their natural habitat would be a primary example. Non-use 
benefits, in contrast, represent welfare gains from ``just knowing' 
that a particular listed species'' natural habitat is being specially 
managed for the survival and recovery of that species. Both use and 
non-use benefits may occur unaccompanied by any market transactions.
    A primary reason for conducting this analysis is to provide 
information regarding the economic impacts associated with a proposed 
critical habitat designation. Section 4(b)(2) of the Act requires the 
Secretary to designate critical habitat based on the best scientific 
data available after taking into consideration the economic impact, and 
any other relevant impact, of specifying any particular area as 
critical habitat. Economic impacts can be both positive and negative 
and by definition, are observable through market transactions.
    Where data are available, the analysis attempt to recognize and 
measure the net economic impact (i.e., the increased regulatory burden 
less any discernable offsetting market gains), of species conservation 
efforts imposed on regulated entities and the regional economy.
    Under Executive Order 12866, OMB directs Federal agencies to 
provide an assessment of both the social costs and benefits of proposed 
regulatory actions. OMB's Circular A-4 distinguishes two types of 
economic benefits: direct benefits and ancillary benefits. Ancillary 
benefits are defined as favorable impacts of a rulemaking that are 
typically unrelated, or secondary, to the statutory purpose of the 
rulemaking. In the context of critical habitat, the primary purpose of 
the rulemaking (i.e., the direct benefit) is the potential to enhance 
conservation of the species. The published economics literature has 
documented that social welfare benefits can result from the 
conservation and recovery of endangered and threatened species. In its 
guidance for implementing Executive Order 12866, OMB acknowledges that 
it may not be feasible to monetize, or even quantify, the benefits of 
environmental regulations due to either an absence of defensible, 
relevant studies or a lack of resources on the implementing agency's 
part to conduct new research. Rather than rely on economic measures, 
the Service believes that the direct benefits of the proposed rule are 
best expressed in biological terms that can be weighed against the 
expected cost impacts of the rulemaking.
    We have accordingly considered, in evaluating the benefits of 
excluding versus including specific areas, the biological benefits that 
may occur to a species from designation (see below, Exclusions Under 
section 4(b)(2) of the Act), but these biological benefits are not 
addressed in the economic analysis.
    37. Comment: One commenter stated that Section 9 of the ESA is 
flawed, and allows extirpation of plants in areas outside federal 
jurisdiction. The comment asserts that critical habitat is important to 
the conservation of the species by prohibiting take, requiring 
mitigation and facilitating the development of recovery plans.
    Our Response: Critical habitat does not prohibit take of plants on 
private lands, or require mitigation for private activities. Critical 
Habitat only affects private activities when a project requires a 
Federal permit, approval or funding. The Act requires the Service to 
develop recovery plans independent of critical habitat designations.
    38. Comment: One commenter thought that the cost estimated in the 
economic analysis was too high because it includes costs attributable 
to listing as opposed to costs of critical habitat designation. A 
second commenter asserted that it was unlawful to report the 
coextensive costs of conserving the species and that only the 
incremental costs resulting from critical habitat should be reported.
    Our Response: The primary purpose of the economic analysis is to 
estimate the potential economic impacts associated with the designation 
of critical habitat for these two species. We interpret the Act to 
require that the economic analysis include all of the economic impacts 
associated with the conservation of the species, which may include some 
of the effects associated with listing. We note that the Act generally 
requires critical habitat to be designated at the time of listing, and 
if we had conducted an economic analysis at that time, the impacts 
associated with listing would not be readily distinguishable from those 
associated with critical habitat designation.
    39. Comment: One commenter indicated that the majority of lands 
designated as critical habitat are already conserved as open space and 
thus not likely to be developed.
    Our Response: We agree that a significant amount of land within the 
areas proposed as critical habitat has been conserved as open space via 
long-term agreements. We have detailed these agreements for each unit 
of proposed critical habitat. Projected development in the economic 
analysis is limited to areas that fall outside these conservation 
commitments.
    40. Comment: One commenter asserted that SCAG projections are 
inadequate since they fail to consider local zoning requirements and 
capture only the potential for development in various regions.
    Our Response: The SCAG development projections are the best 
information available on the extent, timing and placement of real 
estate development in the Los Angeles metropolitan region. These 
forecasts are based on aggregate projections of economic activity and 
employment, as well as location-specific factors such as zoning and 
other local factors.
    41. Comment: One commenter stated that the costs presented in Table 
1 of the Draft Economic Analyses are overstated because portions of 
proposed critical habitat are public lands.
    Our Response: The totals presented in Table 1 are associated with 
development occurring on private land only.

[[Page 66382]]

    42. Comment: One public comment stated that there is a discrepancy 
in the ``Surplus per Developed Acre'' between Table 1 and the text.
    Our Response: Table 1 is correct, however, the corresponding figure 
presented in the text ($2,714,359) is not. This has been corrected in 
the final economic analysis.
    43. Comment: One commenter stated that the small business analyses 
are incomplete.
    Our Response: These sections have been expanded in the final 
economic analyses.
    44. Comment: One commenter stated that it is unclear how the IMPLAN 
(economic modeling software) analyses calculated such a high number 
when the designation of critical habitat does not prevent development.
    Our Response: The regional economic analysis considers the 
secondary effects of housing construction within the areas proposed as 
critical habitat. We note, however, that estimated secondary effects 
are small when considered as a fraction of the total contribution of 
the housing industry to the Southern California economy.
    45. Comment: One commenter stated that it is unclear how the IMPLAN 
Analyses evaluates the secondary effects of critical habitat 
designation on other industries.
    Our Response: Section V Regional Economic Impacts contains an 
explanation of how IMPLAN, which is an input-output model, computes 
indirect and induced effects. See also Table 3, which breaks down the 
secondary effects of designation to each industry.
    46. Comment: One commenter asserted that the costs presented in 
Table 1 are significantly higher than they should be because they are 
associated with the designation on public and private lands.
    Our Response: The costs presented in the reports are estimated 
based on the private land projected for development, not the public and 
private land proposed for critical habitat designation.
    47. Comment: One commenter stated that there are other 
discrepancies between the text and Table 1, including the ``Projected 
Households''.
    Our Response: Table 1 presents the projected households, which is 
consistent with the projected households in the text. Table 3 presents 
the households allowed by zoning, which is also consistent with the 
zoning allowances in the text.
    48. Comment: One commenter requested to be excluded under 4(b)(2) 
of the Act based on economic impacts of critical habitat on their 
property. The landowner owns the property within the proposed Unit 6 
for Pentachaeta lyonii and has proposed to develop 81 residential units 
on the property.
    Our Response: Section 4(b)(2) of the Act requires the Secretary to 
designate critical habitat based on the best scientific data available 
after taking into consideration the economic impact, impact on national 
security, and any other relevant impact, of specifying any particular 
area as critical habitat. We received additional information from the 
landowner in a Memorandum, dated March 3, 2006, which estimated that 
the lost revenue as a result of critical habitat on their proposed 
development, if they avoided impacts to the species, would be 
approximately $78 million. As a result, Unit 6 in its entirety has been 
excluded from the final rule. See Exclusions Under Section 4(b)(2) of 
the Act section below for more details.

Summary of Changes From Proposed Rule

    (1) We modified our criteria for delineating the outer boundaries 
of each unit resulting in minor reductions in unit sizes. In the 
proposed rule, the outer boundaries of each unit or subunit extended to 
984 ft (300 m) on all sides of each mapped patch, which would 
presumably incorporate the minimum size habitat necessary to support 
associated insect pollinators. However, A. brauntonii and P. lyonii are 
known to be pollinated by several insect pollinators, and nonspecific 
pollinators are not a Primary Constituent Element (PCE) for either 
species. Upon further consideration, we felt we needed to better define 
and map the critical habitat boundaries. In looking at the mapping 
information from all mapped records (i.e., from the CNDDB database and 
from records collected from other sources