Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for the Sonoma County Distinct Population Segment of the California Tiger Salamander, 74138-74163 [05-23701]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 70, Number 239 (Wednesday, December 14, 2005)]
[Rules and Regulations]
[Pages 74138-74163]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-23701]



[[Page 74137]]

-----------------------------------------------------------------------

Part III





Department of the Interior





-----------------------------------------------------------------------



Fish and Wildlife Service



-----------------------------------------------------------------------



50 CFR Part 17



Endangered and Threatened Wildlife and Plants; Designation of Critical 
Habitat for the Sonoma County Distinct Population Segment of the 
California Tiger Salamander; Final Rule

Federal Register / Vol. 70, No. 239 / Wednesday, December 14, 2005 / 
Rules and Regulations

[[Page 74138]]


-----------------------------------------------------------------------

DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AU23


Endangered and Threatened Wildlife and Plants; Designation of 
Critical Habitat for the Sonoma County Distinct Population Segment of 
the California Tiger Salamander

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Final decision in rulemaking process.

-----------------------------------------------------------------------

SUMMARY: We, the U.S. Fish and Wildlife Service (Service), designate 
and exclude approximately 17,418 acres (ac) (7,049 hectares (ha)) of 
critical habitat for the Sonoma County distinct population segment of 
the California tiger salamander (Ambystoma californiense) pursuant to 
the Endangered Species Act of 1973, as amended (Act). We are excluding 
all critical habitat based on interim conservation strategies and 
measures being implemented by those local governing agencies with land 
use authority over the area and also as a result of economic exclusions 
authorized under section 4(b)(2) of the Act. Therefore, no critical 
habitat is being designated for the Sonoma County distinct population 
segment of the California tiger salamander in Sonoma County, 
California.

DATES: This final decision becomes effective on January 13, 2006.

ADDRESSES: Comments and materials received, as well as supporting 
documentation used in the preparation of this rulemaking, will be 
available for public inspection, by appointment, during normal business 
hours, at the Sacramento Fish and Wildlife Office (SFWO), 2800 Cottage 
Way, W-2605, Sacramento, CA 95825. The final rule and economic analysis 
will be available via the Internet at https://www.fws.gov/sacramento/.

FOR FURTHER INFORMATION CONTACT: Field Supervisor, Sacramento Fish and 
Wildlife Office, at the above address, (telephone (916) 414-6600; 
facsimile (916) 414-6712).

SUPPLEMENTARY INFORMATION:

Designation of Critical Habitat Provides Little Additional Protection 
to Species

    In 30 years of implementing the Act, the Service has found that the 
designation of statutory critical habitat provides little additional 
protection to most listed species, while consuming significant amounts 
of available conservation resources. The Service's present system for 
designating critical habitat has evolved since its original statutory 
prescription into a process that provides little real conservation 
benefit, is driven by litigation and the courts rather than biology, 
limits our ability to fully evaluate the science involved, consumes 
enormous agency resources, and imposes huge social and economic costs. 
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.

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

    While attention to and protection of habitat is paramount to 
successful conservation actions, we have consistently found that, in 
most circumstances, the designation of critical habitat is of little 
additional value for most listed species, yet it consumes large amounts 
of conservation resources. Sidle (1987) stated, ``Because the Act can 
protect species with and without critical habitat designation, critical 
habitat designation may be redundant to the other consultation 
requirements of section 7.'' Currently, only 466 species or 36.7 
percent of the 1,269 listed species in the United States under the 
jurisdiction of the Service have designated critical habitat.
    We address the habitat needs of all 1,269 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, and 
the Section 10 incidental take permit process. The Service believes 
that it is these measures that may make the difference for the 
conservation of many species.
    We note, however, that two courts found our definition of adverse 
modification to be invalid (March 15, 2001, decision of the United 
States Court Appeals for the Fifth Circuit, Sierra Club v. U.S. Fish 
and Wildlife Service et al., F.3d 434 and the August 6, 2004, Ninth 
Circuit judicial opinion, Gifford Pinchot Task Force v. United States 
Fish and Wildlife Service). On December 9, 2004, the Director issued 
guidance to be used in making section 7 adverse modification 
determinations.

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 almost no ability to provide for adequate 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 impacts from critical habitat designations challenge those 
designations. The cycle of litigation appears endless, is very 
expensive, and in the final analysis provides relatively little 
additional protection to listed 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). None of these costs result in 
any benefit to the species that is not already afforded by the 
protections of the Act enumerated earlier, and they 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 the Sonoma County distinct population segment of the California 
tiger salamander, refer to the final listing rule and proposed critical 
habitat rule

[[Page 74139]]

published in the Federal Register on March 19, 2003 (68 FR 13498), and 
August 2, 2005 (70 FR 44301), respectively.
    As previously mentioned in the proposed critical habitat rule 
published in the Federal Register on August 2, 2005 (70 FR 44301), we 
have been cooperatively working with Federal, State, County, and local 
officials as well as representatives from local business and 
environmental groups over the last 18 months to develop a conservation 
strategy for the California tiger salamander in Sonoma County. The 
development of the Santa Rosa Plain Conservation Strategy (Conservation 
Strategy) along with implementation measures has been moving forward 
and the County of Sonoma along with the cities of Santa Rosa, Rohnert 
Park, Cotati and Windsor have all passed resolutions supporting the 
development and agree to work toward implementation of the Conservation 
Strategy for the protection of the Sonoma County distinct population 
segment of the California tiger salamander as well as several other 
Federally listed plant species occurring on the Santa Rosa Plain.
    On June 29, 2005, the Service and the California Department of Fish 
and Game (CDFG) issued interim guidelines which contain project 
specific conservation measures for projects affecting the California 
tiger salamander on the Santa Rosa Plain. These interim guidelines are 
in place and the measures identified in them are currently being 
implemented by those individuals impacting habitat features considered 
essential for the conservation of the Sonoma County distinct population 
segment of the California tiger salamander. These conservation measures 
have been reviewed by the team developing the Conservation Strategy as 
well as peer reviewed by biologists knowledgeable of amphibian 
conservation or ecological conservation in general and are consistent 
with long-term conservation of the California tiger salamander and 
other listed plants on the Santa Rosa Plain. As the Conservation 
Strategy is finalized, the Service and the CDFG intend to continue to 
implement and or revise these interim guidelines to best conserve the 
California tiger salamander and other Federally-listed plant species on 
the Santa Rosa Plain.

Previous Federal Actions

    On October 13, 2004, a complaint was filed in the U.S. District 
Court for the Northern District of California (Center for Biological 
Diversity and Environmental Defense Council v. U.S. Fish and Wildlife 
Service et al. (Case No. C-04 4324 FMS)). On February 3, 2005, the 
District Court required the Service to submit for publication in the 
Federal Register, a final determination on the proposed critical 
habitat designation on or before December 1, 2005. On August 2, 2005, 
we noticed in the Federal Register a proposed critical habitat 
designation (70 FR 44301). On August 19, 2005, a court order was filed 
on the above complaint, which upheld the section 4(d) rule exempting 
grazing from Section 9 prohibitions, but vacated the downlisting of the 
Santa Barbara and Sonoma populations and reinstated their endangered 
distinct population segment status. On October 25, 2005, we noticed in 
the Federal Register the availability of a draft economic analysis on 
the proposed designation (70 FR 61591). In a November 17, 2005 Federal 
Register notice (70 FR 69717), we requested comments on a refinement of 
those areas considered to contain the essential features necessary for 
the conservation of the Sonoma County distinct population segment of 
the California tiger salamander, and identified the adjusted economic 
impacts. This final decision associated with the rulemaking process is 
in accordance with the settlement agreement and court order. For more 
information on previous Federal actions concerning the California tiger 
salamander, refer to the proposed rule to designate critical habitat in 
Sonoma County published in the Federal Register on August 2, 2005 (70 
FR 44301), as well as the listing notice published in the Federal 
Register on March 19, 2003 (68 FR 13498).

Summary of Comments and Recommendations

    We requested written comments from the public on the proposed 
designation of critical habitat for California tiger salamander in the 
proposed rule published on August 2, 2005 (70 FR 44301). We also 
contacted appropriate Federal, State, and local agencies; scientific 
organizations; and other interested parties and invited them to comment 
on the proposed rule. In addition, we held two public hearings on 
September 8, 2005, in Santa Rosa, California.
    We had three open comment periods, totaling 91 days, between August 
2, 2005 and November 28, 2005. During those periods, we received 
comments directly addressing the proposed critical habitat designation: 
three from peer reviewers, six from local government, and 55 from 
organizations or individuals. We reviewed all comments received from 
the peer reviewers and the public for substantive issues and new 
information regarding critical habitat for the Sonoma County distinct 
population segment of the California tiger salamander. Comments 
received were grouped into general issues specifically relating to the 
proposed critical habitat rulemaking for the Sonoma County distinct 
population segment of the California tiger salamander, are addressed in 
the following summary, and incorporated into the final rule as 
appropriate.

Comments From the State

    Section 4(i) of the Act states, ``the Secretary shall submit to the 
State agency a written justification for her failure to adopt 
regulation consistent with the agency's comments or petition.'' We did 
not receive any comments from State agencies regarding the proposal to 
designate critical habitat for the Sonoma County distinct population 
segment of the California tiger salamander.

Peer Review

    In accordance with our policy published on July 1, 1994 (59 FR 
34270), we solicited expert opinions from six 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 a response from three of the peer 
reviewers. These reviewers provided specific information regarding 
species location and habitat as well as information on the areas that 
could be excluded based on soil information, locations of wetlands, 
potential breeding habitat, elevation information, and habitat 
fragmentation. This information was used to assist us in determining 
the final critical habitat boundaries. Any changes as a result of peer 
review information are reflected and incorporated in this final 
rulemaking as appropriate. Specific peer review comments are addressed 
in the following summary below.

Peer Review Comments

    Comment: The critical habitat area should be reduced to 
approximately 18,000-20,000+ acres of extant occupied habitat and 
comprised of a 1.3 mile (mi) (2 kilometer (km)) buffer around known 
breeding locations.
    Our Response: As outlined in our notice published in the Federal 
Register on November 17, 2005 (70 FR 69717), we refined the proposed 
designation to just those areas surrounding known breeding locations, 
and by applying parameters for dispersal and upland habitat similar to 
those we used in critical habitat designation for the Santa

[[Page 74140]]

Barbara and Central populations of the California tiger salamander. We 
began mapping habitat by buffering breeding locations by a distance of 
0.70 mi (1.1 km) to capture dispersal and upland habitat use by the 
species. Some research has found that 99 percent of interpond dispersal 
would be captured using this 0.7 mi (1.1 km) radius around a breeding 
pond (Trenham et al. 2001; Trenham and Shaffer 2005). Salamanders have 
been documented dispersing even farther than 0.7 mi (1.1 km) (Sweet 
1998) however, and the Conservation Strategy chose a radius of 1.3 mi 
(2.1 km) to ensure that incidental take coverage would be inclusive of 
all areas likely to be occupied by salamanders and to establish a broad 
area in which conservation for salamander would be implemented. 
Ultimately however, as discussed below, we excluded all areas 
designation as critical habitat (see Application of Exclusions Under 
Section 4(b)(2) of the Act).
    Comment: Existing urban centers within the historic range of 
California tiger salamander should be removed from the designation. 
Retaining these urban centers will bias the economic evaluation of 
critical habitat.
    Our Response: In our final designation, we mapped only those areas 
which contained the essential features necessary to conserve the Sonoma 
County distinct population segment of the California tiger salamander. 
We removed all developed and nonessential areas to the best of our 
ability, however due to mapping precision we were unable to remove all 
such development. The scale of the maps prepared under the parameters 
for publication within the Code of Federal Regulations may not reflect 
the exclusion of such developed areas. Any such structures and the land 
under them left inside the critical habitat boundaries shown on the 
maps of this final rule have been excluded by text in the rule and are 
not designated as critical habitat. These developed and nonessential 
habitat areas although within the boundary of the final designation 
would not contain the primary constituent elements and as such would 
not be considered critical habitat. We excluded all the final critical 
habitat based on implementation of local government management 
strategies and economic cost (see Exclusions Under Section 4(b)(2) of 
the Act section).
    Comment: There is anecdotal evidence of one adult California tiger 
salamander near Rainsville Road in the 1990s from an amateur 
herpetologist and the critical habitat boundary should extend south to 
Rainsville Road, north of Petaluma.
    Our Response: As part of our deliberation over which areas to 
designate, we used currently known California tiger salamander breeding 
locations within Sonoma County. We believe that basing our designation 
on breeding locations would ensure the conservation of the species by 
providing areas which contain the essential features of aquatic, 
upland, and dispersal habitats. We lacked adequate documentation of 
essential features, particularly breeding habitat, that might be 
associated with this observation to include it in a critical habitat 
designation. 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. For these reasons, 
critical habitat designations do not signal that habitat outside the 
designation is unimportant or may not be required for recovery. Areas 
that support populations, but are outside the critical habitat 
designation, will continue to be subject to the regulatory protections 
afforded by the section 7(a)(2) jeopardy standard as determined on the 
basis of the best available information at the time of the action.

Other Comments

Issue 1: Habitat and Species Specific Information

    Comment: A few comments stated they were in favor of including the 
Petaluma area as critical habitat because they have observed 
salamanders in this area and suitable habitat exists.
    Our Response: We have been unable to confirm the claims of these 
comments. Breeding or individual observations of the species in the 
Petaluma area have yet to be verified by recognized experts. Since the 
emergency listing in July, 2002, we have received numerous claims from 
the public that they have seen salamanders at various locations within 
the potential range of the species. Upon further investigation by 
recognized experts in those instances, the arboreal salamander (Aneides 
lugubris) is frequently mistaken for the California tiger salamander 
and no confirmed breeding areas for the California tiger salamander 
have been confirmed outside those identified during this rulemaking 
process.

Issue 2: Unit Designations

    Comment: Several comments included specific recommendations on how 
the critical habitat unit(s) should be designed including specific 
areas which should be included and excluded from the final designation.
    Our Response: We used the best scientific information available in 
determining the extent of the critical habitat boundaries and revised 
our proposed rule based on comments received and peer review. We mapped 
only those areas which contained the essential features necessary to 
conserve the Sonoma County distinct population segment of the 
California tiger salamander. When determining critical habitat 
boundaries, we made every effort to avoid including within the 
boundaries of the map contained within this final rule developed areas 
such as buildings, paved areas, and other structures that lack the 
primary constituent elements for the California tiger salamander. The 
scale of the maps prepared under the parameters for publication within 
the Code of Federal Regulations may not reflect the exclusion of such 
developed areas. Any such structures and the land under them 
inadvertently left inside critical habitat boundaries shown on the maps 
of this final rule have been excluded by text in the rule and are not 
designated as critical habitat. These developed and nonessential 
habitat areas would not contain the primary constituent elements and as 
such would not be considered critical habitat. We excluded all the area 
which would otherwise have been designated as final critical habitat 
based on implementation of local government management strategies and 
economic cost (see Exclusions Under Section 4(b)(2) of the Act 
section).
    Comment: One commenter stated that critical habitat unit is too 
limited and that California tiger salamanders have been observed south 
to Muir Woods, Marin County.
    Our Response: We used the best scientific data available for the 
designation of critical habitat and alternative considered for the 
Sonoma County distinct population segment of the California tiger 
salamander, as per section 3(5)(A)(i) of the Act and regulations at 50 
CFR 424.12. We used the California Natural Diversity Database (CNDDB), 
survey records, and other information to determine the historical and 
potential range of the species at the time of listing in March 2003. 
There are no confirmed records of the Sonoma County distinct population 
segment of the California tiger salamander found in Marin County.
    Comment: Several commenters stated that the extension of California 
tiger salamander critical habitat into the Petaluma area is not 
justified based on the current known locations of the

[[Page 74141]]

species and distribution of California tiger salamander habitats. 
Several commenters also stated that the Petaluma area is nearly 
completely developed and lacks the primary constituent elements, the 
designation would cause significant economic impacts; and that the 
lands within the Petaluma city limit should be excluded from critical 
habitat.
    Our Response: We used the best scientific information available in 
determining the extent of the critical habitat boundaries and revised 
our proposed rule based on comments received and peer review. The area 
which otherwise would have received a designation as critical habitat 
is based on known breeding locations for the species. As a result, the 
area south of Pepper Road in Cotati was not considered essential to the 
conservation of the species. In addition, as a result of analyzing the 
benefits of designating critical habitat versus benefits of not 
designating critical habitat we excluded all the final critical habitat 
based on implementation of local government management conservation 
strategies and economic costs (see Exclusions Under Section 4(b)(2) of 
the Act section). Although the area considered essential in the final 
determination does not include the Petaluma area, this does not mean 
that the area does not contain appropriate habitat for the California 
tiger salamander or that the area may be needed for recovery of the 
species. We continue to encourage all local governmental municipalities 
to work closely with State and Federal resource agencies to conserve 
and protect endangered and sensitive species and their habitats.
    Comment: One commenter recommends excluding the areas north of 
Santa Rosa Creek; within the 100 year flood plain; east of Highway 101 
from Rohnert Park Expressway north; and south of Pepper Road to Lichau 
Creek.
    Our Response: We have revised the areas considered as critical 
habitat based on scientific information, peer review, and comments 
received. As a result, we have removed many areas from the proposed 
rule that did not contain the essential features. Also our final 
determination has excluded all the remaining area which otherwise would 
have been designated as critical habitat based on implementation of 
local government management strategies and economic cost (see 
Exclusions Under Section 4(b)(2) of the Act section).

Issue 3: Social and Economic Costs/Regulatory Burden

    Comment: Several commenters requested excluding the lands in the 
City of Santa Rosa's urban grown boundary as critical habitat because 
of their concerns of high economic impacts.
    Our Response: Section 4 of the Endangered Species Act of 1973, as 
amended, and our implementing regulations, state that critical habitat 
shall be designated for species listed under the Act. We have excluded 
all areas which otherwise would have been designated as critical 
habitat, including areas within the City of Santa Rosa urban growth 
boundary (UGB), after taking into consideration the economic impact and 
conservation measures being implemented by local governmental agencies 
(see Exclusions Under Section 4(b)(2) of the Act section).
    Comment: One commenter expressed concern about the burden on 
agricultural practices such as plowing fields, planting new vines, and 
the removal of existing vines.
    Our Response: Designation of critical habitat in areas occupied by 
the species does not necessarily result in a regulatory burden above 
that already in place due to the presence of the listed species. The 
Service works with private landowners to identify activities and 
modifications to activities that will not result in take, to develop 
measures to minimize the potential for take, and to provide 
authorizations for take through Sections 7 and 10 of the Act. One 
intention of critical habitat is to inform people of areas that contain 
the features that are essential for the conservation of the species. We 
encourage landowners to work in partnership with us to develop plans 
that allow their land management and development practices to proceed 
in a manner consistent with the conservation of listed species. The 
California tiger salamander is already a Federally-listed species, and 
as such, projects that may result in take of the species are already 
required to consult with the Service under Section 7 or Section 10 of 
the Act. However, we excluded all areas which otherwise would have been 
designated as critical habitat based on implementation of local 
government management strategies and economic cost (see Exclusions 
Under Section 4(b)(2) of the Act section).

Issue 4: Notification and Comment Period Comments

    Comment: One commenter stated that the comment period was too short 
and the information about the Conservation Strategy was not available 
until just recently.
    Our Response: The proposed critical habitat designation was 
published in the Federal Register on August 2, 2005 (70 FR 44301), and 
we accepted comments from all interested parties for a 60-day comment 
period, until October 3, 2005. On October 25, 2005, we reopened the 
comment period for 21 days until November 14, 2005, and made available 
the draft economic analysis (70 FR 61591). On November 17, 2005, we 
reopened the comment period for 12 days until November 28, 2005 (70 FR 
69717), and requested comments on a refinement of those areas 
considered to contain the essential features necessary for the 
conservation of the Sonoma County distinct population segment of the 
California tiger salamander. The Conservation Strategy was released for 
public comment on August 17, 2005. The document was posted on the 
websites of the City of Santa Rosa and the Sacramento Fish and Wildlife 
Office of the U.S. Fish and Wildlife Service. The Service issued a 
press release and local media reported the event. A public meeting to 
accept comments and provide information was held in Santa Rosa on 
September 12, 2005. The public comment period closed on the 
Conservation Strategy on September 17, 2005.

Issue 5: Designation Process

    Comment: One commenter stated that the proposed rule's boilerplate 
position statement that critical habitat provides no additional benefit 
to listed species violates the Act's requirement that the Service base 
its determinations solely on the best available science.
    Our Response: The Service's statements regarding the general 
protections provided by critical habitat does not change the method in 
which we make our final critical habitat determinations. We used the 
best scientific data available in determining the extent of the area 
which would be designated as critical habitat absent exclusions and in 
identifying areas which contain the features essential to the 
conservation of the species.
    Comment: One commenter stated that the proposed rule implies that 
if the Service does not receive justification for inclusion of an area 
during the public comment period, then that area will be dropped from 
the final critical habitat designation. The commenter also stated that 
the Service needs to make its decision on the basis of the best 
available scientific information and where the information is not 
completely clear or incomplete, the benefit of the doubt should go 
toward actions which would benefit conservation of the species.
    Our Response: It was not our intent to suggest that areas would be 
removed from the designation if information was

[[Page 74142]]

not received to justify their inclusion. We based the final critical 
habitat on the best scientific information available as well as 
incorporated appropriate peer review information. We believe that the 
final area identified as critical habitat prior to exclusion under 
section 4(b)(2) represents the best scientific information as to what 
areas contain the essential features necessary for conservation of the 
Sonoma County distinct population segment of the California tiger 
salamander considering the economic and other relevant impacts.
    Comment: One commenter stated that the Service needs to narrow the 
scope of the proposed critical habitat and not include the entire 
geographical area that can be occupied by the threatened or endangered 
species.
    Our Response: The final boundaries of that area which would be 
designated as critical habitat prior to exclusion under section 4(b)(2) 
for the Sonoma County distinct population segment of the California 
tiger salamander has been greatly reduced from the proposed 
designation. Based on the best scientific data available, we removed 
those areas from the proposed designation which did not contain the 
essential habitat features, were already developed, or were outside the 
current range of the species. The final area which would be designated 
as critical habitat absent exclusion under section 4(b)(2) is based on 
the aquatic, upland and dispersal habitat surrounding known breeding 
locations.

Issue 6: Cooperative Efforts

    Comment: One commenter expressed their support of the cooperative/
partnership approach being used by the Conservation Strategy members. 
They stated that designating critical habitat would provide 
disincentives to private landowners by requiring farmers and ranchers 
obtaining funds from the U.S. Department of Agriculture through the 
Farm Bill to complete the consultation process, which hinders the 
completion of conservation activities on these lands.
    Our Response: We support all cooperative/partnership efforts to 
conserve federally listed threatened and endangered species. Federal 
agencies already consult with us on activities (i.e., permitting or 
funding of projects) in areas currently occupied by the species or if 
the species may be affected by the action to ensure that their actions 
do not jeopardize the continued existence of the species. Therefore, we 
believe that the designation of critical habitat would not likely 
result in significant additional regulatory burden above that already 
in place due to the presence of the listed species. However, we 
excluded all the area which would otherwise be designated as critical 
habitat based on implementation of local government management 
strategies and economic cost (see Application of Exclusions Under 
Section 4(b)(2) of the Act section).

Issue 8: Conservation Strategy

    Comment: One commenter stated that identifying the Conservation 
Strategy as an alternative to designating critical habitat is not 
appropriate or lawful under the Endangered Species Act.
    Our Response: We did not propose the Conservation Strategy to be an 
alternative to designating critical habitat. However, Section 4(b)(2) 
of the Act states that ``The Secretary may exclude any area from 
critical habitat if [s]he determines that the benefits of such 
exclusion outweigh the benefits of specifying such area as part of the 
critical habitat, unless [s]he determines, based on the best scientific 
data available, that the failure to designate such area as critical 
habitat will result in the extinction of the species concerned.'' We 
excluded all the area which would otherwise have been designated as 
critical habitat based on implementation of local government management 
strategies and economic cost (see Application of Exclusions Under 
Section 4(b)(2) of the Act section).
    Comment: Several commenters expressed support of the Conservation 
Strategy, but had reservations because it was not finalized and that it 
needs improvement in order to conserve the Sonoma County distinct 
population segment of the California tiger salamander and four 
Federally-listed plants.
    Our Response: In development of the Conservation Strategy, the 
Federal, State, County and local government agencies, as well as 
representatives from the building industry and environmental 
organizations, received similar comments regarding issues with the 
Conservation Strategy. The Conservation Strategy has been independently 
peer reviewed and comments received from peer reviewers have been 
incorporated into the current version of the plan. The Conservation 
Strategy focuses on establishing large, contiguous preserves and a 
coordinated region-wide restoration and management strategy, species 
research, endowment funding, administration of preserve management, and 
implementation that will contribute to the recovery of the California 
tiger salamander and four Federal and State listed plants in Sonoma 
County. The County of Sonoma, the City of Santa Rosa, the City of 
Cotati, the Town of Windsor, the City of Rohnert Park, the California 
Department of Fish and Game, and the Service have signed a planning 
agreement and the local jurisdictions adopted individual resolutions 
that agree to implement an interim conservation strategy while the 
Conservation Strategy is fully adopted and implemented. We have 
outlined those reasons why we believe the current Conservation Strategy 
would provide a benefit above that of designating critical habitat (see 
Exclusion Under Section 4(b)(2) of the Act section). However, the 
Conservation Strategy is still under development and subject to final 
approval. Should the current Conservation Strategy not be implemented 
or changed to such an extent as it no longer provides for the 
conservation of the Sonoma County distinct population segment of the 
California tiger salamander, we would revisit our current determination 
on designating critical habitat for the species and repropose critical 
habitat.
    Comment: One commenter stated that the Service needs to protect the 
areas where the California tiger salamander reside rather than relocate 
them as is identified in the Conservation Strategy.
    Our Response: The designation of critical habitat does not 
prescribe management actions but does define areas which contain the 
essential features described as primary constituent elements. We agree 
that protection of areas where California tiger salamanders are endemic 
should be the priority of the strategy, and this is demonstrated by the 
conservation areas identified in the Conservation Strategy. The 
Conservation Strategy identifies areas that support potential habitat 
but is not currently occupied by the California tiger salamander and 
recommends translocation of the species to be an option only under 
certain circumstances. These areas may be suitable for translocation of 
individuals to aid in the recovery of the species. Some projects 
authorized under Section 7 or 10 of the ESA may have unavoidable 
impacts to the species. These unavoidable impacts may be minimized by 
salvaging individuals and relocating them to suitable habitat on a case 
by case basis. Preliminary data has demonstrated that this management 
technique may be successful. The Conservation Strategy has been peer 
reviewed by recognized experts and the comments regarding translocation 
have been incorporated into the current version of the plan.

[[Page 74143]]

Issue 9: Economic Analysis

    Comment: One commenter states that the Draft Economic Analysis 
(DEA) fails to evaluate benefits associated with conserving the 
California tiger salamander. Further, this commenter states that the 
DEA should review the benefits of conserving open space and riparian 
areas.
    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 
essential to the conservation of listed species. While a listed species 
may be the primary beneficiary of designated critical habitat, the 
designation of critical habitat may also result in two distinct 
categories of benefits to society: (1) Use, and (2) non-use benefits. 
Use benefits are 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 
conservation 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, this analysis attempts to recognize and 
measure the net economic impact of the proposed designation. For 
example, the DEA investigates whether conserved open space at 
designated mitigation sites results in increased property values. The 
DEA did not find any evidence that housing price was influenced by 
proximity to the nearest conservation area. The authors hypothesize 
that this may be attributable to the large amount of open space in 
Sonoma County. While section 4(b)(2) of the Act gives the Secretary 
discretion to exclude certain areas from the final designation, she is 
authorized to do so only if an exclusion does not result in the 
extinction of the species. In terms of carrying out its 
responsibilities under section 4(b)(2) then, the Service need only to 
consider whether the economic impacts (both positive and negative) or 
any other impact are significant enough to merit exclusion of any 
particular area without causing the species to go extinct.
    Comment: One commenter states that the DEA overestimates costs 
associated with conserving California tiger salamander, because it 
includes economic impacts attributable to listing under the Act. The 
commenter further states that the DEA confuses the economic costs by 
including costs of conservation efforts to protect the species (not its 
critical habitat) with conservation of the proposed critical habitat. 
For this reason, the commenter questions why the DEA includes pre-
designation costs, as these costs are associated with listing of the 
species.
    Our Response: This analysis identifies those economic activities 
believed to most likely threaten the California tiger salamander and 
its habitat and, where possible, quantifies the economic impact to 
avoid, mitigate, or compensate for such threats within the boundaries 
of the critical habitat. In instances where critical habitat is being 
proposed after a species is listed, some future impacts may be 
unavoidable, regardless of the final designation and exclusions under 
4(b)(2). However, due to the difficulty in making a credible 
distinction between listing and critical habitat effects within 
critical habitat boundaries, this analysis considers all future 
conservation-related impacts to be coextensive with the designation.
    Comment: Several commenters state that the DEA should incorporate 
the recent ruling in the Ninth Circuit Court of Appeals, Gifford 
Pinchot Task Force v. U.S. Fish and Wildlife Service.
    Our Response: The DEA acknowledges that the Ninth Circuit judicial 
opinion, Gifford Pinchot Task Force v. United States Fish and Wildlife 
Service, invalidated the Service's regulation defining destruction or 
adverse modification of critical habitat. The Service is currently 
reviewing the decision to determine what affect it (and to a limited 
extent Center for Biological Diversity v. Bureau of Land Management 
(Case No. C-03-2509-SI, N.D. Cal.)) may have on the outcome of 
consultations pursuant to section 7 of the Act. As a result of this 
ruling, the DEA assumes that efforts to mitigate impacts to the habitat 
must occur within the boundaries of critical habitat. Consistent with 
this requirement, zonal mitigation sites assumed in the DEA are those 
identified in the Santa Rosa Plain Conservation Strategy.
    Comment: Several commenters state that the DEA underestimates the 
impact of critical habitat on transportation projects in Sonoma County.
    Our Response: Planned transportation projects are captured in the 
DEA using the California Department of Transportation's California 
Transportation Investment System (CTIS) tool that includes information 
for interstates, principal arterials, and rural minor arterials. The 
CTIS tool incorporates information about projects overseen by the State 
Transportation Improvement Program, the State Highway Operations and 
Protection Program, the Interregional Transportation Strategic Plan, 
the California Aviation System Plan, and various regional 
transportation planning organizations. Version 1.3.2 of this tool is 
used in the DEA as the updated Version 2.0 had not been released at the 
time the report was prepared. Accordingly, the DEA is prepared using 
the most current publicly available information on planned 
transportation projects. Public comments received were inadequate to 
update impact calculations.
    Based on the public comments received, the Service's contractor for 
completing the economic analysis contacted the Sonoma County 
Transportation Authority (Authority) to request more detailed 
information on the nature, location and scope of additional planned 
projects. The Authority was unable to provide the needed information in 
time to revise the impact analysis within the court-directed timeframe. 
However, since no critical habitat is being designated, the impacts 
asserted by the commenter will not be incurred.
    Comment: Several commenters state that mitigation prices used in 
the DEA are too low. The comments further cite a wide range of current 
market prices for mitigation in Sonoma County.
    Our Response: The DEA calculates mitigation prices as the cost of 
land assembly in the various California tiger salamander mitigation 
zones plus the cost of required improvements to land to make the site 
suitable for California tiger salamander occupation. This approach is 
consistent with the welfare-theoretic underpinnings of the impact 
model, in particular its focus on efficiency effects. One social cost 
of using land for mitigation is the value of the foregone alternative 
uses of the land. These values are approximately equal to the purchase 
price of the land. Another social cost of mitigation is the value of 
the resources used to modify the land to make it suitable for 
California tiger salamander occupation.

[[Page 74144]]

    Mitigation prices may rise above the supply price of mitigation, 
for example when the supply of mitigation is constrained by permitting 
delays or other factors. However, prices above supply cost are a 
transfer between agents and net out of an efficiency impact.
    Comment: Two commenters state that the DEA should not use 
mitigation formulas described in the Conservation Strategy since it is 
not a legally binding document. Further, the commenters state that the 
DEA should not assume that critical habitat has no impacts outside of a 
1.3-mile buffer around breeding habitat.
    Our Response: The cities of Santa Rosa, Rohnert Park, and Cotati, 
the town of Windsor, Sonoma County, the local development community, 
environmental organizations, the Service, and other federal and state 
agencies have undertaken a process to support California tiger 
salamander conservation at a regional level. This effort has involved 
extensive scientific research and analysis of the biological and 
ecological issues relating to California tiger salamander and of its 
specific circumstances in the region. During the week of November 7, 
2005, all of the local jurisdictions formally approved execution of a 
planning agreement that commits them to work with the Service and other 
parties to finalize and implement the Conservation Strategy. Indeed, 
one economic cost of critical habitat may be to disrupt and impose 
additional costs on this collaborative effort.
    Comment: Two commenters state that the DEA underestimates or 
ignores potential impacts to agriculture. In particular, commenters are 
concerned that the DEA does not quantify impacts to the wine grape 
industry and does not quantify increases in production costs or 
decreases in agricultural land values resulting from critical habitat.
    Our Response: The DEA quantifies the reduction in agricultural land 
values resulting from foregone or constrained land development 
opportunities. A review of available biological opinions did not reveal 
any evidence of limitations on crop production practices resulting from 
listing of the California tiger salamander.
    The DEA acknowledges that critical habitat may increase the costs 
and reduce the economic optimality of vineyard development within 
critical habitat. However, given the relative abundance of substitute 
vineyard sites within Sonoma County relative to the forecasted increase 
in vineyard acreage, it is speculative at present to assign costs to 
this potential impact.

Summary of Changes From Proposed Rule

    In the proposed critical habitat rule for the Sonoma County 
distinct population segment of the California tiger salamander, we 
identified the historical and potential range of the species in Sonoma 
County, utilizing all known breeding and adult locality data and GIS 
resources available to the Service. Based on comments received from the 
public and from peer review, and a refinement of our parameters for 
dispersal and upland habitat use by the species, we revised the final 
designation of critical habitat for the Sonoma County distinct 
population segment of the California tiger salamander, as follows:
    (1) As outlined in our notice published in the Federal Register on 
November 17, 2005 (70 FR 69717), we refined the proposed designation by 
applying parameters for dispersal and upland habitat similar to those 
we used in critical habitat designation for the Santa Barbara and 
Central populations of the California tiger salamander. We began 
mapping habitat by buffering known salamander breeding locations by a 
distance of 0.70 mi (1.1 km) to capture dispersal and upland habitat 
use by the species. We adjusted the 0.70 mi (1.1 km) area around 
breeding sites depending on habitat availability, dispersal barriers, 
and development and removed areas which did not contain the essential 
features. See Methodology and Criteria Sections below for more 
information.
    (2) We revised the proposed critical habitat unit based on comments 
and biological information and peer review received during the public 
comment periods.
    (3) Collectively, we excluded or removed the entire designation. 
Some areas in the proposed rule were removed because they did not 
contain the primary constituent elements. Other areas were excluded 
based on conservation measures being implemented by the local 
government agencies, or because of disproportionately high economic 
costs, as authorized under section 4(b)(2) of the Act (see 
``Application of Exclusions Under Section 4(b)(2) of the Act'' section 
below).

Critical Habitat

    Critical habitat is defined in section 3 of the Act as--(i) 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 (I) essential to the conservation 
of the species and (II) that may require special management 
considerations or protection; and (ii) 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'' means the use of all methods and 
procedures that are necessary to bring an endangered or a threatened 
species to the point at which listing under the Act is no longer 
necessary.
    Critical habitat receives protection under section 7 of the Act 
through the prohibition against destruction or adverse modification of 
critical habitat with regard to actions carried out, funded, or 
authorized by a Federal agency. Section 7 requires consultation on 
Federal actions that are likely to result in the destruction or adverse 
modification of critical habitat. The designation of critical habitat 
does not affect land ownership or establish a refuge, wilderness, 
reserve, preserve, or other conservation area. Such designation does 
not allow government or public access to private lands.
    To be included in a critical habitat designation, the habitat 
within the area occupied by the species must first have 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 (i.e., areas on which are found the primary constituent 
elements, as defined at 50 CFR 424.12(b)).
    Habitat occupied at the time of listing may be included in critical 
habitat only if the essential features thereon may require special 
management or protection. Thus, we do not include areas where existing 
management is sufficient to conserve the species (as discussed below, 
such areas may also be excluded from critical habitat pursuant to 
section 4(b)(2)). Accordingly, when the best available scientific data 
do not demonstrate that the conservation needs of the species so 
require, we will not designate critical habitat in areas outside the 
geographical area occupied by the species at the time of listing. An 
area currently occupied by the species but was not known to be occupied 
at the time of listing will likely be essential to the conservation of 
the species and, therefore, included in the critical habitat 
designation.
    The Service's Policy on Information Standards Under the Endangered 
Species Act, published in the Federal Register on July 1, 1994 (59 FR 
34271), and Section 515 of the Treasury and General Government 
Appropriations

[[Page 74145]]

Act for Fiscal Year 2001 (Pub. L. 106-554; H.R. 5658) and the 
associated Information Quality Guidelines issued by the Service, 
provide criteria, establish procedures, and provide guidance to ensure 
that decisions made by the Service represent the best scientific and 
commercial data available. They require Service biologists to the 
extent consistent with the Act and with the use of the best scientific 
and commercial data available, to use primary and original sources of 
information as the basis for recommendations to designate critical 
habitat. When determining which areas are critical habitat, a primary 
source of information is generally the listing package 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. All information is used in 
accordance with the provisions of Section 515 of the Treasury and 
General Government Appropriations Act for Fiscal Year 2001 (Pub. L. 
106-554; H.R. 5658) and the associated Information Quality Guidelines 
issued by the Service.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific data available. 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 conservation of the species. For these reasons, 
critical habitat designations do not signal that habitat outside the 
designation is unimportant or may not be required for recovery.
    Areas that support populations, but are outside the critical 
habitat designation, will continue to be subject to conservation 
actions implemented under section 7(a)(1) of the Act and to the 
regulatory protections afforded by the section 7(a)(2) jeopardy 
standard, as determined on the basis of the best available information 
at the time of the 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, or 
other species conservation planning efforts if new information 
available to these planning efforts calls for a different outcome.

Methods

    As required by section 4(b)(1)(A) of the Act, we use the best 
scientific data available in determining areas that contain the 
features that are essential to the conservation of the Sonoma County 
distinct population segment of the California tiger salamander. In 
determining the areas to designate critical habitat for the California 
tiger salamander, we used the best scientific data available. We have 
reviewed the overall approach to the conservation of the Sonoma County 
distinct population segment of the California tiger salamander 
undertaken by local, State, and Federal agencies operating within the 
species' range since its listing in 2003 (68 FR 13498).
    We have also reviewed available information that pertains to the 
habitat requirements of this species. The material included data in 
reports submitted during section 7 consultations and by biologists 
holding section 10(a)(1)(A) recovery permits; research published in 
peer-reviewed articles and presented in academic theses and agency 
reports; and regional Geographic Information System (GIS) coverages.

Primary Constituent Elements

    In accordance with section 3(5)(A)(i) of the Act and regulations at 
50 CFR 424.12, in determining which areas to propose as critical 
habitat, we are required to base critical habitat determinations on the 
best scientific data available and to consider those physical and 
biological features (primary constituent elements (PCEs)) that are 
essential to the conservation of the species, and that may require 
special management considerations and protection. These include, but 
are not limited to: Space for individual and population growth and for 
normal behavior; food, water, air, light, minerals, or other 
nutritional or physiological requirements; cover or shelter; sites for 
breeding, reproduction, and rearing (or development) of offspring; and 
habitats that are protected from disturbance or are representative of 
the historic geographical and ecological distribution of a species.
    The specific primary constituent elements required for the 
California tiger salamander are derived from the biological needs of 
the California tiger salamander as described below and in the 
Background section of this designation and previous listing or critical 
habitat designation for the species.
    The areas determined to contain the features essential for the 
conservation of the California tiger salamander are designed to provide 
sufficient aquatic habitat for breeding and upland habitat as refugia 
for adults to maintain and sustain populations of California tiger 
salamanders throughout their range, and provide those habitat 
components necessary for the species. Conserving California tiger 
salamanders over the long term requires a three-pronged approach: (1) 
Protecting the hydrology and water quality of breeding pools and ponds; 
(2) retaining or providing for connectivity between breeding locations 
for genetic exchange and recolonization; and (3) protecting sufficient 
upland habitat around each breeding location to allow for enough adult 
survival to maintain a breeding population over the long term. In our 
determination of the amount of critical habitat to designate, we 
focused on identifying those areas which contained the features which 
would provide the breeding and upland habitat to maintain and sustain 
existing populations of salamanders in documented breeding sites 
(vernal pool complexes) identified within Sonoma County. Due to the 
complex life history and dispersal capabilities of California tiger 
salamanders, and the dynamic nature of the environments in which they 
are found, the primary constituent elements described below should be 
found throughout the unit that is being identified as critical habitat. 
Critical habitat for the Sonoma County distinct population segment of 
the California tiger salamander will provide for breeding and 
nonbreeding habitat and for dispersal between these habitats, as well 
as allowing for an increase in the size of the Sonoma County distinct 
population segment of the California tiger salamander.

Space for Individual and Population Growth and Normal Behavior

    California tiger salamanders require a combination of aquatic 
habitat and upland habitat in order to successfully maintain normal 
population growth and behavior. Aquatic habitat is essential for 
California tiger salamander breeding and for providing space, food, and 
cover necessary to sustain early life history stages of California 
tiger salamanders. Breeding habitat consists of fresh water bodies, 
including natural and man-made ponds, vernal pools, or other ephemeral 
or permanent wetland features which allow California tiger salamanders 
to complete their aquatic portion of their lifecycle. To be considered 
essential, aquatic habitats must have the potential

[[Page 74146]]

to hold water for a minimum of 12 weeks in the winter or spring in a 
year of average rainfall. This is the amount of time needed for 
juveniles to complete metamorphosis and become capable of surviving in 
upland habitats. During periods of drought or less-than average 
rainfall, these breeding sites may not hold water long enough for 
individuals to complete metamorphosis, but these sites would still be 
considered because they constitute breeding habitat in years of average 
rainfall. Without its essential aquatic habitat features, the 
California tiger salamander would not survive, because breeding could 
not occur.

Upland Habitat

    Associated upland habitat containing underground refugia is 
essential for the survival of adult California tiger salamanders and 
juveniles that have recently undergone metamorphosis. Adult and 
juvenile California tiger salamanders are terrestrial, and they enter 
aquatic habitats only for short periods of time to breed. For the 
majority of their life cycle, California tiger salamanders depend for 
survival on upland habitats containing underground or covered refugia 
where they are protected from desiccation. Juveniles have been found in 
soil cracks and rodent burrows and adults almost exclusively in rodent 
burrows. These underground refugia provide protection from the hot, dry 
weather in the nonbreeding season (Shaffer and Trenham 2005). 
California tiger salamanders also find food in small mammal burrows and 
rely on the burrows for protection from predators. The upland areas 
also regulate the hydrological functioning and protect water quality of 
the aquatic habitat (Hanes and Stromberg 1998). As described in 
previous rules (69 FR 68572; 70 FR 49380), California tiger salamanders 
have been found up to 1.3 mi (2 km) from occupied occurrences (Sweet, 
1998). The only known study we are aware of that specifically 
investigated movement of California tiger salamanders between breeding 
ponds projected that 0.70 mi (1.1 km) would encompass 99 percent of 
interpond dispersal (Trenham et al. 2001; Trenham and Shaffer 2005). As 
we did for the Santa Barbara and Central populations, we used the 0.70 
mi (1.1 km) away from breeding location to identify those upland 
habitat features essential for the Sonoma County distinct population 
segment of the California tiger salamander.

Food

    California tiger salamanders use both aquatic and terrestrial 
habitat during their lifecycle. As a result California tiger 
salamanders require areas which support a prey base of both aquatic 
(e.g., zooplankton, aquatic larvae, aquatic invertebrates, tadpoles, 
etc.) and terrestrial (e.g., terrestrial invertebrates, insects, frogs, 
worms, etc.) species. The aquatic and upland habitat features would 
support the necessary prey base in all aspects of the California tiger 
salamander lifecycle.

Reproduction

    Lifetime reproductive success for California and other tiger 
salamanders is low. Trenham et al. (2000) found the average female bred 
1.4 times and produced 8.5 young that survived to metamorphosis per 
reproductive effort. This resulted in roughly 11 metamorphic offspring 
over the lifetime of a female. In part, this low reproductive success 
is due to the extended time it takes for California tiger salamanders 
to reach sexual maturity: Most do not breed until 4 or 5 years of age. 
While individuals may survive for more than 10 years, many breed only 
once. Combined with low survivorship of metamorphosed individuals (in 
some populations, less than 5 percent of marked juveniles survive to 
become breeding adults (Trenham et al. 2000)), reproductive output in 
most years is not sufficient to maintain populations. This trend 
suggests that the species requires occasional ``boom'' breeding events 
to prevent extirpation (temporary or permanent loss of the species from 
a particular habitat) or extinction (Trenham et al. 2000). With such 
low recruitment, isolated populations are susceptible to unusual, 
randomly occurring natural events as well as from human-caused factors 
that reduce breeding success and individual survival. Factors that 
repeatedly lower breeding success in isolated pools can quickly 
extirpate a population. California tiger salamanders would require an 
interconnected network of ponds and upland areas so that they can 
disperse from one pond to nearby ponds in order to augment or 
recolonize locally extirpated ponds and uplands.

Dispersal Habitat

    Protecting the ability of California tiger salamanders to move 
freely across the landscape in search of breeding ponds is essential in 
maintain