Endangered and Threatened Wildlife and Plants; Designation of Critical Habitat for Ceanothus ophiochilus, 54984-55010 [07-4723]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 72, Number 187 (Thursday, September 27, 2007)]
[Rules and Regulations]
[Pages 54984-55010]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 07-4723]



[[Page 54983]]

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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 20



Endangered and Threatened Wildlife and Plants; Designation of Critical 
Habitat for Ceanothus ophiochilus (Vail Lake ceanothus) and 
Fremontodendron mexicanum (Mexican flannelbush); Final Rule

Federal Register / Vol. 72, No. 187 / Thursday, September 27, 2007 / 
Rules and Regulations

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AU77


Endangered and Threatened Wildlife and Plants; Designation of 
Critical Habitat for Ceanothus ophiochilus (Vail Lake ceanothus) and 
Fremontodendron mexicanum (Mexican flannelbush)

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 Ceanothus ophiochilus (Vail Lake 
ceanothus) and Fremontodendron mexicanum (Mexican flannelbush) under 
the Endangered Species Act of 1973, as amended (Act). In total, 
approximately 431 acres (ac) (175 hectares (ha)) of federally-owned 
land fall within the boundaries of the critical habitat designation for 
these two species. Approximately 203 ac (82 ha) of land in Riverside 
County, California, are being designated as critical habitat for C. 
ophiochilus, and approximately 228 ac (93 ha) of land in San Diego 
County, California, are being designated as critical habitat for F. 
mexicanum. Of the approximately 283 ac (115 ha) proposed for 
designation for C. ophiochilus, approximately 80 ac (33 ha) of 
privately-owned land covered by the Western Riverside County Multiple 
Species Habitat Conservation Plan (MSHCP) have been excluded from 
critical habitat for C. ophiochilus under section 4(b)(2) of the Act. 
Of the approximately 361 ac (147 ha) proposed for designation for F. 
mexicanum, approximately 133 ac (54 ha) of privately-owned land covered 
by the San Diego Multiple Species Conservation Plan (MSCP) have been 
excluded from critical habitat for F. mexicanum under section 4(b)(2) 
of the Act.

DATES: This rule becomes effective on October 29, 2007.

ADDRESSES: Comments and materials received, as well as supporting 
documentation used in the preparation of this final rule, will be 
available for public inspection, by appointment, during normal business 
hours, at the U.S. Fish and Wildlife Service, Carlsbad Fish and 
Wildlife Office, 6010 Hidden Valley Road, Carlsbad, CA 92011 (telephone 
760-431-9440). The final rule, economic analysis, and maps will also be 
available via the Internet at https://www.fws.gov/carlsbad/.

FOR FURTHER INFORMATION CONTACT: Jim Bartel, Field Supervisor, Carlsbad 
Fish and Wildlife Office (see ADDRESSES); telephone 760-431-9440; 
facsimile 760-431-5901. If you use a telecommunications device for the 
deaf (TDD), call the Federal Information Relay Service (FIRS) at 800-
877-8339.


SUPPLEMENTARY INFORMATION:

Background

    It is our intent to discuss only those topics directly relevant to 
the designation of critical habitat in this final rule. For more 
information on Ceanothus ophiochilus and Fremontodendron mexicanum, 
refer to the final listing rule published in the Federal Register on 
October 13, 1998 (63 FR 54956), or the proposed critical habitat rule 
published in the Federal Register on October 3, 2006 (71 FR 58340).

Species Descriptions and Life History

    No new information pertaining to the descriptions or life histories 
of these species was received following the 2006 proposed designation 
of critical habitat for each species; therefore, please refer to the 
proposed critical habitat designation published in the Federal Register 
on October 3, 2006 (71 FR 58340) for a discussion of the species 
description and life history for these two species.

Ecology and Habitat

    No new information pertaining to the ecology or habitat of these 
two species was received following the 2006 proposed designation of 
critical habitat for each species. Therefore, please refer to the 
proposed critical habitat designation published in the Federal Register 
on October 3, 2006 (71 FR 58340), for a discussion of the ecology and 
habitat for these two species.

Distribution

    In 2007, an occurrence of Fremontodendron mexicanum was documented 
at the historical ``Woodwardia Canyon'' occurrence on Otay Mountain, 
which was last documented in 1936 (Snapp-Cook 2007, p. 1). Prior to the 
rediscovery of this occurrence, the exact location of ``Woodwardia 
Canyon'' was difficult to discern from existing records. There were no 
maps of ``Woodwardia Canyon'' and the California Natural Diversity 
Database (CNDDB) cited ``Woodwardia Canyon'' in two separate areas 
(CNDDB 2005, p. 1 and p. 3). The rediscovered occurrence is located on 
Otay Mountain 0.3 miles (mi) (0.5 kilometers (km)) to the southwest of 
the known occurrence of F. mexicanum in Little Cedar Canyon, and is not 
within the area designated as critical habitat. Approximately 500 F. 
mexicanum were documented at this rediscovered occurrence (Snapp-Cook 
2007, p. 1). The significance of this occurrence and its impact on 
designated critical habitat will need to be further evaluated by the 
Service. Appropriate action, if any, will be addressed in a future 
rulemaking. For a detailed discussion of the distribution of F. 
mexicanum and Ceanothus ophiochilus documented prior to this final 
designation, please refer to the proposed critical habitat designation 
published in the Federal Register on October 3, 2006 (71 FR 58340).

Previous Federal Actions

    On August 10, 2004, the Center for Biological Diversity and 
California Native Plant Society challenged our failure to designate 
critical habitat for these two species as well as three other plant 
species (Center for Biological Diversity, et al. v. Gale Norton, 
Secretary of the Department of the Interior, et al., C-04-3240 JL, N. 
D. Cal.). In a Settlement Agreement dated December 21, 2004, we agreed 
to submit for publication in the Federal Register a proposed 
designation of critical habitat, if prudent and determinable, on or 
before September 20, 2006, and a final determination by September 20, 
2007. As part of the 2006 proposed designation we determined that it 
was prudent to designate critical habitat for each of these two 
species. The combined proposed critical habitat designation for both 
species was signed on September 18, 2006, and published in the Federal 
Register on October 3, 2006 (71 FR 58340). This final rule completes 
the Service's obligations regarding these species under the December 
21, 2004, settlement agreement.
    A draft economic analysis (DEA) for the proposed designation was 
completed on March 2, 2007, and a notice of availability for this DEA 
was published in the Federal Register on April 5, 2007 (72 FR 16756). 
Publication of the notice of availability opened a public comment 
period for the draft economic analysis of the proposed designation as 
well as the proposed designation from April 5, 2007, to May 7, 2007. 
Please refer to the ``Previous Federal Actions'' section of the 
proposed critical habitat rule for Ceanothus ophiochilus and 
Fremontodendron mexicanum, which published in the Federal Register on 
October 3, 2006 (71 FR 58340) for a discussion of additional Federal 
actions

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that occurred prior to the designation of critical habitat for each 
species.

Summary of Comments and Recommendations

    We requested written comments from the public on the proposed 
designation of critical habitat for Ceanothus ophiochilus and 
Fremontodendron mexicanum in the proposed rule that published on 
October 3, 2006 (71 FR 58340), and in the notice of availability of the 
DEA published on April 5, 2007 (72 FR 16756). We also contacted 
appropriate Federal, State, and local agencies; scientific 
organizations; and other interested parties and invited them to comment 
on the proposed rule and the DEA.
    During the comment period that opened on October 3, 2006, and 
closed on December 4, 2006, we received three comments directly 
addressing the proposed critical habitat designation: Two from peer 
reviewers and one from the County of San Diego. We did not receive any 
requests for a public hearing during this first comment period. A 
second comment period opened on April 5, 2007, to allow for comment on 
the DEA and the proposed critical habitat. During the comment period 
that opened on April 5, 2007, and closed on May 7, 2007, we received 
seven comments directly addressing the proposed critical habitat 
designation and the draft economic analysis. Of these latter comments, 
two were from peer reviewers, one was from a Federal agency, two were 
from local governments, one was from an organization, and one was from 
an individual.

Peer Review

    In accordance with our policy published on July 1, 1994 (59 FR 
34270), we solicited expert opinions from five 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 four of the 
peer reviewers. The peer reviewers generally concurred with our methods 
and conclusions and one peer reviewer commented that the information 
for Fremontodendron mexicanum was well researched and complete.
    All comments are addressed in the following summary and 
incorporated into the final rule as appropriate.
    Peer Reviewer Comments
    1. Comment: One peer reviewer requested that we clarify the 
statement that Ceanothus ophiochilus is found on metavolcanic 
substrate. The peer reviewer indicated that the 1977 Jennings Geologic 
Maps do not indicate any metavolcanic substrate, only gabbro substrate 
in the vicinity of species occurrences.
    Response: We reviewed the soils information for this species. 
Geological maps that are more recent than the 1977 Jennings Geologic 
Maps are available. These maps indicate that the area around Vail Lake 
and in the Agua Tibia Wilderness, where Ceanothus ophiochilus is found, 
consists of metavolcanic, metasedimentary, and Gabbro substrates 
(Kennedy et al. 2000, p. 1; and Kennedy and Mertz 2003, p. 1).
    2. Comment: One peer reviewer stated that the Ceanothus ophiochilus 
population in Subunit 1A near Vail Lake is important to the 
preservation of the genetic purity of this species and should not be 
excluded from critical habitat because the Western Riverside County 
Multiple Species Habitat Conservation Plan (MSHCP) does not adequately 
protect this population. The peer reviewer made the following points to 
the argument that this population is important and should be protected:
    a. In the proposed rule we wrote that Ceanothus ophiochilus 
``appears'' to hybridize with C. crassifolius; however, the peer 
reviewer commented that C. ophiochilus ``does'' hybridize with C. 
crassifolius and that there are several specimens deposited at the 
herbarium of Rancho Santa Ana Botanic Garden which document the 
hybridization of these two species.
    b. The peer reviewer commented that both Ceanothus ophiochilus and 
C. crassifolius are members of the subgenus Cerastes. All members of 
this subgenus lack a burl and are obligate seeders. The peer reviewer 
states that because both of these species only regenerate from seeds 
following a fire and that the two species hybridize, the threat of 
hybridization is a threat to the survival of the species.
    c. The peer reviewer commented that the occurrences near Vail Lake 
and the occurrences in the Agua Tibia wilderness are affected 
differently by hybrids because Ceanothus crassifolius grows immediately 
adjacent to the C. ophiochilus in the Agua Tibia Wilderness and these 
two species are separated by 0.25 mi (0.4 km) in Vail Lake.
    d. The peer reviewer commented that due to soil disturbance from 
roads and fuel breaks within the populations of Ceanothus ophiochilus 
in the Agua Tibia Wilderness, hybrid plants are now more interspersed 
with the population. The greater amount of hybrid individuals may 
increase the relative likelihood of further introgressive hybridization 
within the new cohort of C. ophiochilus. This contrasts with the 
populations near Vail Lake where the natural distance to C. 
crassifolius populations is greater and there has not been disturbance 
within the population.
    These factors lead to the conclusion that the population at Vail 
Lake has a much better chance of keeping the pure form of C. 
ophiochilus intact and lower the risk caused by hybridization.
    Response: We agree with the peer reviewer's comments on the 
potential problems associated with hybridization, and we have made the 
appropriate changes to this final rule to clarify that hybridization is 
a threat to this species (please see the ``Primary Constituent 
Elements'' section for Ceanothus ophiochilus). However, we disagree 
with the peer reviewer's comment that Subunit 1A for C. ophiochilus 
should not be excluded from critical habitat because the Western 
Riverside County MSHCP does not adequately protect this population. The 
Western Riverside County MSHCP provides measures to benefit the 
conservation of C. ophiochilus by: protecting habitat from surface-
disturbing activities; implementing specific management and monitoring 
practices to help ensure the conservation of C. ophiochilus in the 
MSHCP Conservation Area; maintaining the physical and ecological 
characteristics of occupied habitat; and conducting surveys and 
implementing other required procedures to ensure avoidance of impacts 
to at least 90 percent of suitable habitat areas determined important 
to the long-term conservation of C. ophiochilus within the Criteria 
Area. As discussed in the proposed critical habitat rule, the exclusion 
of critical habitat does not dismiss or lessen the value that the Vail 
Lake population has to the overall conservation of this species. 
Rather, we have determined that the benefits of excluding Subunit 1A 
are greater than the benefits of including the subunit, and the 
exclusion of Subunit 1A will not result in the extinction of the 
species (please see the ``Relationship of Critical Habitat to Habitat 
Conservation Plan Lands --Exclusions Under Section 4(b)(2) of the Act'' 
section of this final rule for a detailed discussion).
    3. Comment: A second peer reviewer commented that the hybridization 
between Ceanothus ophiochilus and C. crassifolius may result in the 
loss of homogeneous C. ophiochilus populations at some sites. This is 
especially true in those populations where the C. crassifolius 
significantly outnumbers C. ophiochilus or where the two species are in 
close contact. The

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reviewer further commented that management plans need to take this 
potential problem into consideration.
    Response: The information provided by this peer reviewer and the 
previous peer reviewer help to explain why hybridization threatens this 
species. We have made the appropriate changes to this final rule to 
clarify that hybridization is a threat to the species (please see 
``Primary Constituent Elements'' section for Ceanothus ophiochilus and 
the ``Special Management Considerations or Protection'' section). We 
have based this critical habitat designation on the best scientific and 
commercial data available. Currently, we are unaware of any studies 
specifically addressing the extent to which these two species are 
hybridizing. We also do not have information on the reproductive 
characteristics of the hybrid plants in the wild. However, we agree 
that researching the issue of hybridization as it relates to C. 
ophiochilus will be important to the conservation of this species.
    4. Comment: One peer reviewer stated that Ceanothus ophiochilus 
will not survive in the long term if intentionally exposed to fire-
suppression. The peer reviewer stated that this species is unable to 
reproduce vegetatively and requires fire to prepare seeds for 
germination and provide an open, mineral-rich soil free from 
competition among seedlings. The peer reviewer commented that plans for 
managing critical habitat need to take this natural process into 
consideration.
    Response: Designation of critical habitat does not necessarily 
require changes to existing management plans. However, we have 
incorporated this information as it relates to the potential impacts of 
fire-suppression into the ``Primary Constituent Elements'' section for 
Ceanothus ophiochilus of this final rule, so it will be considered in 
any relevant future section 7 consultations. We will also encourage 
parties to consider the effects of fire-suppression when developing 
management plans covering areas supporting essential habitat for C. 
ophiochilus.
    5. Comment: One peer reviewer indicated that the seeds of 
Fremontodendron decumbens differ from the seeds of F. mexicanum. 
Fremontodendron decumbens seeds have an orange waxy protrusion called a 
caruncle. The caruncle attracts ants which in turn disperse the seeds. 
It has been reported that F. mexicanum does not have a caruncle. The 
peer reviewer commented that this should be verified through a formal 
study because the presence or absence of a caruncle has important 
implications in the regeneration ecology of seed dispersal in this 
species and, therefore, its continued persistence.
    Response: As required under the Act, we have based this critical 
habitat designation on the best scientific and commercial data 
available. We agree that investigating the seed dispersal mechanism for 
Fremontodendron mexicanum and the relationship with ants or other 
possible dispersers is important. We encourage further study and will 
continue to investigate dispersal mechanisms as we work towards the 
conservation of the species.

Public Comments

    6. Comment: The County of San Diego commented that private lands in 
subunits 1A and 1B occupied by Fremontodendron mexicanum are entirely 
within a designated preserve area that will be protected and managed 
under the San Diego MSCP. The County provided specific information on 
the monitoring and management activities that will benefit this species 
and requested that lands covered by the MSCP be excluded from the final 
designation under section 4(b)(2) of the Act.
    Response: In the proposed rule, we requested comments on the 
appropriateness of excluding lands occupied by Fremontodendron 
mexicanum covered by the San Diego MSCP but did not propose these lands 
for exclusion. Based on comments we received during the public comment 
periods for the proposed rule, we have determined that even though F. 
mexicanum is not a covered species under the San Diego MSCP, private 
lands occupied by this species will be conserved under the San Diego 
MSCP through the Otay Ranch Phase 2 Resource Management Plan. The Otay 
Ranch Phase 2 Resource Management Plan includes specific protection 
measures that will benefit F. mexicanum. In addition, these private 
lands will receive management for associated species that are covered 
under the MSCP that is consistent with the biological needs of F. 
mexicanum and preservation of its primary constituent elements. Based 
on the benefits of preserving and fostering our partnerships with these 
local jurisdictions and other non-Federal entities, and after 
considering the conservation benefits provided by the Otay Ranch Phase 
2 Resource Management Plan under the MSCP, we have now determined that 
the benefits of excluding these lands from critical habitat outweigh 
the benefits of including these lands, and we have, therefore, excluded 
133 ac (54 ha) of private lands proposed as critical habitat for this 
species from this final designation under section 4(b)(2) of the Act 
(see the ``Relationship of Critical Habitat to Habitat Conservation 
Plan Lands--Exclusions Under Section 4(b)(2) of the Act'' section of 
this final rule for detailed discussion of the protections provided 
under the MSCP).
    7. Comment: The County indicated that the location of subunit 1A is 
not consistently described in the proposed rule. The County stated the 
proposed rule indicates that subunit 1A for Fremontodendron mexicanum 
is entirely on BLM land, but the map indicates that the subunit 
contains BLM land and private land.
    Response: The proposed rule (71 FR 58340, October 3, 2006) 
indicates that subunit 1A for Fremontodendron mexicanum consists of 
both BLM and private land in the unit description on page 58350 and in 
Table 1 on the same page.
    8. Comment: One commenter requested that we discuss how the 
designation of critical habitat for Ceanothus ophiochilus may 
contribute to the fuel load and the fire hazard in the area around the 
designation. The commenter also requested that we identify range land 
plants species important to healthy rangelands that C. ophiochilus 
could overtake in its recovery after wildfire.
    Response: Ceanothus ophiochilus is a relatively uncommon component 
of chaparral and occurs in very limited areas. We do not believe that 
the conservation of this species will increase the fire danger in areas 
where critical habitat is designated. Management for this species would 
favor a natural fire regime, on the order of once every 20 to 50 years 
(Keeley 2006, p. 367). Ceanothus ophiochilus is restricted to a limited 
soil type found in small patches on ridge-tops and north-facing slopes. 
This species is found in chaparral habitat and not areas that are 
historically range land. Following fire, C. ophiochilus repopulates 
limited areas in chaparral habitat and will not overtake rangelands.
    9. Comment: One commenter stated that the critical habitat 
designation should include all lands occupied by these two species.
    Response: Under section 3(5)(c) of the Act, critical habitat shall 
not include the entire geographical area which can be occupied by the 
species unless otherwise determined by the Secretary. The proposed 
designation of critical habitat for these two species included all of 
the areas known to be occupied by Ceanothus ophiochilus and

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Fremontodendron mexicanum at the time of the proposed rule (71 FR 
58340, October 3, 2006). After critical habitat was proposed for 
Fremontodendron mexicanum, approximately 500 F. mexicanum were 
documented at the location of an historical occurrence on Otay Mountain 
that was previously believed to be extirpated. This rediscovered 
occurrence is not within the area proposed as critical habitat. 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. Therefore, critical habitat designations 
do not signal that habitat outside the designation is unimportant or 
may not be required for recovery.
    10. Comment: One commenter stated that we should include critical 
habitat Subunit 1A for Ceanothus ophiochilus because the Western 
Riverside County Multiple Species Habitat Conservation Plan (MSHCP) 
fails to provide special management to address altered fire regime and 
nonnative species.
    Response: Under the Western Riverside County MSHCP, an adaptive 
management program will be used to meet the conservation goals and 
objectives for this species. The species account for Ceanothus 
ophiochilus in the MSHCP documentation acknowledges that altered fire 
regimes and nonnative invasive species threaten this species. The 
Western Riverside County MSHCP provides a mechanism to address special 
management considerations and protections for the population of C. 
ophiochilus and its primary constituent elements identified for 
conservation under the MSHCP in Subunit 1A. After considering all 
relevant factors, including the conservation measures provided by the 
MSHCP, we have determined that the benefits of excluding lands covered 
by the MSHCP from critical habitat outweigh the benefits of inclusion 
(see ``Relationship of Critical Habitat to Habitat Conservation Plan 
Lands--Exclusions Under Section 4(b)(2) of the Act'' section for a 
detailed discussion of the MSHCP and further explanation of the bases 
for this conclusion).
    11. Comment: One commenter stated that both the Western Riverside 
County MSHCP and U.S. Forest Service's (USFS) Land Management Plan 
(LMP) should be evaluated using the same standards when considering the 
exclusion of critical habitat Subunit 1A and 1B for Ceanothus 
ophiochilus.
    Response: We did evaluate lands covered by the Western Riverside 
County MSHCP and the USFS's Land Management Plan for exclusion from the 
final designation using the same standards under section 4(b)(2) of the 
Act. In considering whether this plan provides adequate management or 
protection for the species for purposes of applying section 4(b)(2) of 
the Act, we evaluated the plan based on the following three criteria: 
(1) The plan is complete and provides the same or a higher level of 
protection from adverse modification or destruction than that provided 
through a consultation under section 7 of the Act; (2) there is a 
reasonable expectation that the conservation management strategies and 
actions will be implemented based on past practices, written guidance, 
or regulations; and (3) the plan provides conservation strategies and 
measures consistent with currently accepted principles of conservation 
biology. As discussed in the ``Relationship of Critical Habitat to 
Habitat Conservation Plan Lands--Exclusions Under Section 4(b)(2) of 
the Act'' section, we believe that the Western Riverside County MSHCP 
fulfills these criteria, and we are excluding non-Federal lands covered 
by this plan that provide for the conservation of Ceanothus ophiochilus 
from the final designation of critical habitat pursuant to section 
4(b)(2) of the Act. The USFS's Land Management Plan contains general 
provisions for conservation of this species, and additional guidance 
documents are available that suggest specific management and 
conservation actions that should be considered. However, the LMP does 
not identify specific management measures to address the threat posed 
by short-interval fires and by competing nonnative species (Zedler 
1983, p. 815; Keeley 2006, p. 367; Merriam et al. 2007, p. vi, v, 48, 
61). Therefore, after analyzing the LMP in light of the criteria 
identified above, we have determined that the LMP does not provide 
management for C. ophiochilus in a manner that provides the same or 
higher level of protection from adverse modification or destruction 
than that provided through a consultation under section 7(a)(2) of the 
Act. In addition, as discussed below in the ``Exclusions under Section 
4(b)(2) of the Act'' section below, we have determined not to exclude 
these Federal lands from the final designation of critical habitat 
pursuant to section 4(b)(2) of the Act.
    12. Comment: One commenter stated that both subunits 1A and 1B for 
Fremontodendron mexicanum need to be retained in the final designation 
of critical habitat, despite the overlap of F. mexicanum with other 
species that are included in the Multiple Habitat Preserve Area/Pre-
approved Mitigation Area of the MSCP for the City and County of San 
Diego.
    Response: Fremontodendron mexicanum is not covered by the San Diego 
MSCP; however, all of the known occurrences of this species occur 
within the preserve design for the MSCP (Pryor 2007, p. 1-2). When the 
private lands where F. mexicanum occurs are conveyed into the MSCP 
preserve, they will be subject to adaptive management activities, 
consistent with the MSCP. Protections, management, and monitoring are 
described in the draft Otay Ranch Phase 2 Resource Management Plan 
(Otay Ranch 2002, p. 141-144; Pryor 2007, p. 2). Therefore, we believe 
that private lands where this species and associated primary 
constituent elements are found will be managed in a way that will help 
to achieve the recovery of this species and have determined that the 
benefits of exclusion outweigh the benefits of inclusion as described 
in the ``Relationship of Critical Habitat to Habitat Conservation Plan 
Lands--Exclusions Under Section 4(b)(2) of the Act'' section.
    13. Comment: One commenter stated that we should use the Primary 
Constituent Elements (PCEs) to model suitable habitat for these species 
and designate suitable unoccupied habitat for these species. The 
commenter stated that the Service should consider and evaluate the 
recovery benefits of critical habitat designation as part of our 
critical habitat designation.
    Response: When determining habitat essential for the conservation 
of these species, we used a set of specific criteria for each species 
(see ``Criteria Used To Identify Critical Habitat'' below for more 
detail). Based on the resulting areas that were identified using these 
criteria, we made the determination that additional, unoccupied areas 
were not essential for the conservation of either species. We believe 
the current distribution of known, occupied locations of both species 
will provide for the conservation and contribute to the recovery of 
these species. Additionally, both of these species occur in very 
limited areas. These species are endemic to a very narrow range, and we 
have determined that the best conservation strategy for these two 
species is to conserve them in the locations where they currently are 
found. Accordingly, when the best available scientific data does not 
demonstrate that the conservation needs of the species require 
additional areas, we will not designate critical habitat in areas 
outside the geographical area occupied by the species at the time of 
listing.

[[Page 54988]]

    When proposing and finalizing critical habitat designations, the 
Service does consider the recovery benefits to species. The 
identification of those lands that are essential for the conservation 
of the species and can, if managed, provide for the recovery of a 
species, is beneficial. The process of proposing and finalizing a 
critical habitat rule provides the Service with the opportunity to 
identify the species' essential primary constituent elements and areas 
essential for the conservation of the species. The designation process 
includes peer review and public comment on the identified features and 
lands. This process is valuable to land owners and managers in 
developing conservation management plans for identified lands, as well 
as any other occupied or unoccupied suitable habitat that may not have 
been included in the Service's determination of essential habitat.
    14. Comment: One commenter requested that we evaluate how an 
exclusion under 4(b)(2) of the Act will affect the recovery of the 
species in addition to whether or not the exclusion will lead to the 
extinction of the species.
    Response: We believe the designation of critical habitat promotes 
the recovery of species, and when proposing and finalizing critical 
habitat designations we do consider the recovery benefits to species. 
When considering an exclusion under section 4(b)(2) of the Act, the 
recovery benefits to the species from designating a particular area as 
critical habitat are fully considered when we determine whether the 
benefits of inclusion of such area are outweighed by the benefits of 
exclusion.
    If we determine that the benefits of excluding a particular area 
from critical habitat outweigh the benefits of including such area, and 
have determined that excluding the area from the final critical habitat 
designation is appropriate, we then evaluate whether that exclusion 
would result in the extinction of the species and provide clear 
explanation for this determination. If we have been considering an 
exclusion that we determine will result in the extinction of a species, 
consistent with the statutory requirements of Section 4(b)(2), we will 
not exclude the area from the critical habitat designation. Please see 
the ``Relationship of Critical Habitat to Habitat Conservation Plan 
Lands--Exclusions Under Section 4(b)(2) of the Act'' section of this 
final rule for a detailed discussion and our determinations that the 
exclusions in this final rule will not result in the extinction of 
Ceanothus ophiochilus or Fremontodendron mexicanum. Areas meeting the 
definition of critical habitat for both C. ophiochilus and F. mexicanum 
occur on private lands. The HCPs in Riverside County and San Diego 
County include these private lands and provide for the management and 
monitoring of these lands as they are conserved. These plans are 
believed to provide for long-term conservation of these lands that the 
designation of critical habitat would not provide (please see the 
``Relationship of Critical Habitat to Habitat Conservation Plan Lands--
Exclusions Under Section 4(b)(2) of the Act'' section of this final 
rule for a detailed discussion).
    15. Comment: One comment stated that the individual supports all of 
the past and on-going conservation efforts that have taken place for 
these two species; however, these conservation efforts are not a 
substitute for critical habitat. The person commented that critical 
habitat complements the conservation goals of habitat conservation 
plans and, by designating critical habitat, the Service assures that 
the Federal Government meets its legal obligation to ensure the 
continued existence and recovery for Ceanothus ophiochilus and 
Fremontodendron mexicanum.
    Response: The process of designating critical habitat does 
complement the existing habitat conservation plans (HCPs). The proposed 
rule identifies areas that meet the definition of critical habitat. 
These areas are then analyzed based on existing land-use planning 
documents, such as HCPs. Based on this analysis, areas may be excluded 
from the final designation of critical habitat, if the benefits of 
exclusion outweigh the benefits of including them in the critical 
habitat designation and the exclusions will not result in the 
extinction of the species. This exclusion analysis considers all 
benefits, including recovery benefits, and through the analysis the 
Service meets all legal requirements for designation of critical 
habitat.
    16. Comment: One commenter expressed support for our exclusion of 
private lands within the Western Riverside County MSHCP; however, the 
commenter stated that all lands covered by the MSHCP, including the 
USFS lands, should be excluded from critical habitat. The commenter 
cited the Implementing Agreement for the MSHCP indicating the Service 
had agreed that ``in the event that a critical habitat determination is 
made for any covered species adequately conserved * * * lands within 
the boundaries of the MSHCP will not be designated as critical habitat 
(Implementing Agreement for the Western Riverside County Multiple 
Species Habitat Conservation Plan, sec. 14.10 at p. 51).''
    Response: In the Biological Opinion for the MSHCP, the Service 
concluded that the proposed conservation strategy would adequately 
conserve Ceanothus ophiochilus and its primary constituent elements 
(Service 2004, p. 402-406). We believe that the conservation mechanisms 
in place under the HCP will adequately conserve the populations and 
primary constituent elements on private lands. Further, the benefits 
analysis provided herein under section 4(b)(2) of the Act determined 
that the benefits of excluding the specific lands from critical habitat 
outweigh the benefits of including them in critical habitat (see the 
``Exclusions under Section 4(b)(2) of the Act'' section of this final 
rule for further details). Therefore, we have excluded private lands 
covered by the MSHCP. We appreciate the conservation work that the USFS 
is doing for C. ophiochilus; however, the USFS is not a signatory to 
the MSHCP permit and therefore is not bound by the requirements of the 
MSHCP. The phrase ``lands within the boundaries of the MSHCP,'' as used 
in the provision of the Implementing Agreement referenced by the 
commenter, refers to lands under the jurisdiction of the MSHCP 
permittees, and does not include federal lands that fall within the 
overall MSHCP boundaries. For the reasons stated in the above response 
to Comment 11, we have determined not to exclude the USFS lands.

Comments From Other Federal Agencies

    17. Comment: The USFS commented that the proposed critical habitat 
contains the occurrences and habitat for Ceanothus ophiochilus on USFS 
land. They also highlighted that the proposed designation stated that 
the Cleveland National Forest (CNF) lands were proposed for designation 
because of impacts to ridge tops from grading associated with the 
creation of fuel breaks, impacts to the associated vegetation community 
from unnatural fire regimes, and nonnative species. While the USFS 
agreed that these threats could damage C. ophiochilus habitat, they 
indicated that their Land Management Plan (LMP) provides for the 
minimization and avoidance of impacts to endangered species. 
Specifically, they indicated that Standard 12 of their LMP states, 
``When occupied or suitable habitat for threatened, endangered, 
proposed, candidate or sensitive species is present on an ongoing or 
proposed project site, consider species guidance documents to develop 
project-specific design criteria.''

[[Page 54989]]

    Response: We acknowledge the efforts the USFS has made towards the 
conservation of the Ceanothus ophiochilus and acknowledge that the LMP 
contains general provisions for conservation of this species. However, 
in considering whether the plan provides adequate management or 
protection for the species for purposes of applying section 4(b)(2) of 
the Act, we evaluated the plan based on the following three criteria: 
(1) The plan is complete and provides the same or a higher level of 
protection from adverse modification or destruction than that provided 
through a consultation under section 7 of the Act; (2) there is a 
reasonable expectation that the conservation management strategies and 
actions will be implemented based on past practices, written guidance, 
or regulations; and (3) the plan provides conservation strategies and 
measures consistent with currently accepted principles of conservation 
biology. The LMP does not identify specific management measures to 
address the threat posed by short-interval fires and by competing 
nonnative species (Keeley 2006, p. 367; Merriam et al. 2007, p. vi, v, 
48, 61). Because the USFS does not have a management plan specific to 
C. ophiochilus that provides the same or better level of protection 
from adverse modification or destruction than that provided through a 
consultation under section 7(a)(2) of the Act, we have determined that 
exclusion of these lands from the final designation of critical habitat 
pursuant to section 4(b)(2) of the Act is not appropriate for these 
Federal lands.
    18. Comment: The USFS commented that like HCPs, the USFS LMPs are 
designed to ensure the long-term survival of covered species in the 
plan area and designed to protect, restore, and enhance the value of 
USFS lands as habitat for listed species. They indicated that their LMP 
provides comparable conservation measures for Ceanothus ophiochilus and 
its primary constituent elements as the Western Riverside County MSHCP, 
and therefore should be excluded from critical habitat under section 
4(b)(2) of the Act.
    Response: Based on a review of the USFS LMP, we do not believe that 
the LMP provides conservation measures for Ceanothus ophiochilus 
comparable to those provided in the Western Riverside County MSHCP. 
During the development of this final designation, we evaluated lands 
covered by the Western Riverside County MSHCP, the USFS's LMP, and 
other relevant conservation plans for exclusion using the same 
standards under section 4(b)(2) of the Act. Please see our response to 
Comment number 11.
    19. Comment: The USFS commented that current laws, regulations, and 
policies, and land management practices on the CNF are adequate to 
provide for the conservation of Ceanothus ophiochilus and its habitat. 
They further state that designation of critical habitat on CNF lands 
would not provide any additional benefit to the conservation of C. 
ophiochilus, or its habitat, and that designation would unnecessarily 
add to their analysis burden by requiring the USFS to make a 
determination of effect regarding critical habitat when consulting 
under section 7(a)(2) of the Act.
    Response: Although the comment letter from the USFS does not 
explicitly request that the lands proposed for designation be excluded 
from final critical habitat, based on their comments we did consider 
their lands for exclusion. We concluded that despite the LMP and other 
regulations that exist, which require the USFS to manage Ceanothus 
ophiochilus and its habitat, the benefits of including this area in 
critical habitat outweigh the benefits of excluding this area from the 
designation of critical habitat (please see the ``Unit Description'' 
section for detailed discussion on the exclusion of the USFS lands in 
this critical habitat determination).

Comments Related To the Draft Economic Analysis

    20. Comment: One commenter stated that the DEA should consider 
potential economic impacts to all occupied and unoccupied but suitable 
habitat, rather than just the areas included in the draft rule.
    Response: In a critical habitat designation, section 4(b)(2) of the 
Act requires that we consider the economic impact of specifying any 
particular area as critical habitat. Therefore, we prepare an economic 
analysis to identify the economic impact of designating areas proposed 
as critical habitat (including any areas proposed for exclusion under 
section 4(b)(2) of the Act). The economic analysis focuses on 
activities within or affecting these areas. Potential economic impacts 
to areas supporting occupied and suitable habitat that are outside the 
boundaries of proposed critical habitat are not relevant to the 
required analysis under section 4(b)(2) of the Act.
    21. Comment: One commenter stated that the DEA overestimates costs 
associated with conserving both Ceanothus ophiochilus and 
Fremontodendron mexicanum, because it includes economic impacts 
attributable to listing under the Act. The comment further states that 
the DEA inaccurately attributes all of the costs to critical habitat 
designation and confuses the economic costs by including costs of 
conservation efforts for the species (not just critical habitat) with 
conservation of the proposed critical habitat.
    Response: The economic analysis estimates the total cost of species 
conservation activities without subtracting the impact of pre-existing 
baseline regulations (i.e., the cost estimates are fully co-extensive). 
In 2001, the U.S. 10th Circuit Court of Appeals instructed the Service 
to conduct a full analysis of all of the economic impacts of proposed 
critical habitat designation, regardless of whether those impacts are 
attributable co-extensively to other causes (New Mexico Cattle Growers 
Ass'n v. USFWS, 248 F.3d 1277 (10th Cir. 2001)). The economic analysis 
for Ceanothus ophiochilus and Fremontodendron mexicanum is consistent 
with this direction from the U.S. 10th Circuit Court of Appeals. The 
analysis identifies those economic activities believed most likely to 
threaten the species and their habitat and, where possible, quantifies 
the economic impact to avoid, mitigate, or compensate for such threats 
within the boundaries of the critical habitat designation. We 
acknowledge that some of these costs will likely be incurred regardless 
of whether critical habitat is designated. However, due to the 
difficulty in making a credible distinction between listing and 
critical habitat effects within critical habitat boundaries, the 
analysis considered all future conservation-related impacts to be 
coextensive with the designation. We have not excluded any areas from 
the final critical habitat designation based on economic impacts under 
section 4(b)(2) of the Act.
    22. Comment: One comment states that the DEA fails to evaluate any 
benefits of conserving a species that is threatened by extinction. The 
comment further notes that in addition to the dollar value of both 
Ceanothus ophiochilus and Fremontodendron mexicanum, there are many 
other values, destined to grow with our knowledge of the species in 
science, medicine, and aesthetics and in ways still unforeseen. The 
same commenter requests that at least some of these values be 
quantified and estimated in the final economic analysis.
    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

[[Page 54990]]

other relevant impact, of specifying any particular area as critical 
habitat. The Service's approach for estimating economic impacts 
includes both economic efficiency and distributional effects. The 
measurement of economic efficiency is based on the concept of 
opportunity costs, which reflect the value of goods and services 
foregone in order to comply with the effects of the designation (e.g., 
lost economic opportunity associated with restrictions on land use). 
Where data are available, the economic analyses do attempt to measure 
the net economic impact. However, no data was found that would allow 
for the measurement of such an impact, nor was such information 
submitted during the public comment period.
    Most of the other benefit categories submitted by the commenter 
reflect broader social values, which are not the same as economic 
impacts. While the Secretary must consider economic and other relevant 
impacts as part of the final decision-making process under section 
4(b)(2) of the Act, the Act explicitly states that it is the 
government's policy to conserve all threatened and endangered species 
and the ecosystems upon which they depend. Thus, we believe that 
explicit consideration of broader social values for the species and 
their habitat, beyond the more traditionally defined economic impacts, 
is not necessary as Congress has already clarified the social 
importance.
    We note, as a practical matter, it is difficult to develop credible 
estimates of such values, as they are not readily observed through 
typical market transactions and can only be inferred through advanced, 
tailor-made studies that are time consuming and expensive to conduct. 
We lacked both the budget and time needed to conduct such research 
before meeting our court-ordered final rule deadline. In summary, we 
believe that Congress has placed significant value on conserving any 
and all threatened and endangered species and the habitats upon which 
they depend, and the critical habitat designation process under section 
4 of the Act incorporates these values. Thus, although we limit the 
scope of the economic analysis to economic impacts (both positive and 
negative), when we consider whether it is appropriate to exclude 
particular areas from critical habitat under section 4(b)(2) of the 
Act, we consider not just economic impacts, but all relevant impacts. 
In doing so, consistent with the value Congress has placed on species 
preservation, conservation benefits for the species at issue derived 
from the designation of critical habitat are afforded appropriate 
weight in the balancing analysis under section 4(b)(2).
    23. Comment: One commenter requested that we identify the potential 
cost of loss of private property and habitat due to wildfires that may 
occur as a result of the designation of critical habitat.
    Response: Ceanothus ophiochilus and Fremontodendron mexicanum are 
adapted to a natural fire regime with wildfire intervals of 
approximately 20 to 50 years. For example, C. ophiochilus reproduces 
after fire from seed. As a result, fire suppression activities can 
considerably limit the species' ability to reproduce because the seeds 
need fire to sprout. However, short-interval fires can also be 
detrimental to the species by preventing plants from reaching 
reproductive maturity and facilitating the establishment of non-native 
grasses that compete for limited space and resources. Federal agencies 
indicated that they would need to develop fire management plans for 
each species. Adoption of species-specific fire management plans, which 
are themselves subject to consultation pursuant to Section 7 of the 
Act, will allow Federal land managers to maintain the natural fire 
regimes required by each species. Fire management plans take 
neighboring properties into account such that application of prescribed 
burns or management of wildfires should occur in such a manner that 
would not increase the risk to surrounding properties and development. 
As such, we do not believe it is appropriate to evaluate the cost of 
the potential loss of private property due to wildfire as a part of 
this designation.
    24. Comment: One commenter stated that the co-extensive costs 
projected in the draft economic analysis are unacceptable.
    Response: In 2001, the U.S. 10th Circuit Court of Appeals 
instructed the Service to conduct a full analysis of all of the 
economic impacts of proposed critical habitat designation, regardless 
of whether those impacts are attributable co-extensively to other 
causes (New Mexico Cattle Growers Ass'n v. USFWS, 248 F.3d 1277 (10th 
Cir. 2001)). The economic analysis for Ceanothus ophiochilus and 
Fremontodendron mexicanum is consistent with this direction from the 
U.S. 10th Circuit Court of Appeals. See response to comment 21.

Summary of Changes From Proposed Rule

    In preparing the final critical habitat designation for Ceanothus 
ophiochilus and Fremontodendron mexicanum, we reviewed and considered 
public and peer review comments on the proposed designation of critical 
habitat and the DEA. As a result of comments received on the proposed 
rule and the DEA, and a reevaluation of the proposed critical habitat 
boundaries, we made the changes identified below to our proposed 
designation.
    In the proposed rule, we requested comments on the appropriateness 
of excluding lands occupied by Fremontodendron mexicanum covered by the 
San Diego MSCP but did not propose these lands for exclusion. Based on 
information we received during the public comment periods for the 
proposed rule, we have determined that even though F. mexicanum is not 
a covered species under the San Diego MSCP, private lands occupied by 
this species will be conserved under the San Diego MSCP through the 
Otay Ranch Phase 2 Resource Management Plan. The management provided by 
the MSCP for other covered species will also benefit the recovery of F. 
mexicanum (see ``Relationship of Critical Habitat to Habitat 
Conservation Plan Lands--Exclusions Under Section 4(b)(2) of the Act'' 
section for further discussion). We reanalyzed the lands covered by the 
MSCP for exclusion and determined that the benefits of excluding these 
lands from critical habitat outweighs the benefits of including them in 
the designation. Therefore, we have excluded 133 ac (54 ha) of private 
lands proposed as critical habitat for this species from this final 
designation under section 4(b)(2) of the Act (see the ``Exclusions 
under Section 4(b)(2) of the Act'' section of this final rule for 
further details).

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, as defined under section 3 of the Act, means 
to use and the use of all methods and procedures that are necessary to 
bring any endangered species or threatened species to the point at 
which the measures provided under the Act are no longer necessary. Such 
methods and

[[Page 54991]]

procedures include, but are not limited to, all activities associated 
with scientific resources management such as research, census, law 
enforcement, habitat acquisition and maintenance, propagation, live 
trapping, and transplantation, and, in the extraordinary case where 
population pressures within a given ecosystem cannot be otherwise 
relieved, may include regulated taking.
    Critical habitat receives protection under section 7 of the Act 
through the prohibition against destruction or adverse modification of 
critical habitat with regard to actions carried out, funded, or 
authorized by a Federal agency. Section 7(a)(2) of the Act requires 
consultation on Federal actions that may affect critical habitat. The 
designation of critical habitat does not affect land ownership or 
establish a refuge, wilderness, reserve, preserve, or other 
conservation area. Such designation does not allow government or public 
access to private lands. Section 7(a)(2) of the Act is a purely 
protective measure and does not require implementation of restoration, 
recovery, or enhancement measures, nor does it apply to private actions 
for which there is no involved Federal action.
    To be included in a critical habitat designation, habitat within 
the geographical 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 (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 considerations or protection. Furthermore, when the best 
available scientific data do not demonstrate that the conservation 
needs of the species require additional areas, we cannot designate 
critical habitat in areas outside the geographical area occupied by the 
species at the time of listing. However, an area currently occupied by 
the species but not occupied at the time of listing, will likely be 
essential to the conservation of the species and, therefore, may be 
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 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 data available. They require Service biologists, to the 
extent consistent with the Act and with the use of the best scientific 
data available, to use primary and original sources of information as 
the basis for recommendations to designate critical habitat. When 
determining which areas are critical habitat, a primary source of 
information is generally the listing package for the species. 
Additional information sources may include the recovery plan for the 
species, articles in peer-reviewed journals, conservation plans 
developed by States and counties, scientific status surveys and 
studies, biological assessments, 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 and commercial 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 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 of Ceanothus ophiochilus and 
Fremontodendron mexicanum, but are outside their respective critical 
habitat designations, 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.

Primary Constituent Elements (PCEs)

    In accordance with section 3(5)(A)(i) of the Act and regulations at 
50 CFR 424.12, in determining which areas to designate as critical 
habitat within areas occupied by the species at time of listing, we 
consider those physical or biological features (primary constituent 
elements (PCEs)) that are essential to the conservation of the species, 
and may require special management considerations or 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 
distributions of a species.

Ceanothus ophiochilus

    The specific primary constituent elements required for Ceanothus 
ophiochilus are derived from the biological and physical needs of the 
species as described in the final listing rule (63 FR 54956, October 
13, 1998), the proposed critical habitat rule (71 FR 58340, October 3, 
2006), and information contained in this final rule.

Space for Growth and Reproduction

    Ceanothus ophiochilus is restricted to ridgetops and north to 
northeast facing slopes in chamise chaparral (PCE 1). It occurs on 
soils formed from metavolcanic and ultra-basic parent materials or 
deeply weathered gabbro substrates, all of which are phosphorus 
deficient and thus considered to be nutrient-poor (PCE 2) (Boyd et al. 
1991, pp. 31, 37-38; Kennedy et al. 2000, p. 1; and Kennedy and Mertz 
2003, p. 1). These soils are similar to serpentine soils, which are 
well known for the high number of associated rare and endemic plants 
(Kruckeberg 1984, pp.3-5, p. 34). The high number of rare and endemic 
plants that grow on nutrient-poor soils, sometimes termed as harsh 
soils, is due to the difficulty that common plants have with growing in 
these conditions. In turn, when plants become established on such 
soils, they remain genetically isolated from close relatives that are 
not able to thrive on the nutrient-poor soils. In this way, these 
nutrient-poor soils may help the species maintain reproductive 
isolation (Boyd et al. 1991, p. 37-38). This is important because C. 
ophiochilus hybridizes with the locally

[[Page 54992]]

common C. crassifolius in places where the two species grow in close 
proximity (Boyd et al. 1991, p. 37-38). Hybrids are generally found on 
the margins of C. ophiochilus occurrences, where the soil changes from 
the harsh metavolcanic and gabbro soils that C. ophiochilus is 
typically found on to the milder sedimentary soils that support species 
such as C. crassifolius (Boyd et al. 1991, p. 37-38). Hybridization is 
a common natural phenomenon among the species of Ceanothus genus 
(Schmidt 1993, p. 935; Fross and Wilken 2006, pp. 131-149), and 
metavolcanic and gabbro soils are important for growth and reproduction 
of C. ophiochilus, as well as for space and separation from C. 
crassifolius, a species with which C. ophiochilus is known to 
hybridize.
    Soils where Ceanothus ophiochilus is found in the Agua Tibia 
Wilderness are mapped as Ramona, Cienaba, and Vista series (USDA 1973, 
pp. 38-40, 70-71, 82-83), but appear to be Las Posas series based on 
field review and soil samples (USFS 1998a). Soils where C. ophiochilus 
is found at Vail Lake are mapped as Cajalco series (USDA 1971, p. 21).
    Ceanothus ophiochilus is found in chamise chaparral or mixed 
chamise-ceanothus-manzanita chaparral at elevations of 2,000 feet (ft) 
to 3,000 ft (610 meters (m) to 914 m) (California Department of Fish 
and Game 2000; California Natural Diversity Database (CNDDB) 2005) with 
the following associated species: Adenostoma fasciculatum, A. 
sparsifolium, Quercus berberidifolia, C. crassifolius, Arctostaphylos 
spp. Salvia clevelandii, and Eriodictyon crassifolium (PCE 3) (Boyd and 
Banks 1995, p. 15). Within chaparral of southern Riverside County, 
these associated species are much more common than C. ophiochilus.
    We have little information about the pollinators or reproductive 
biology of this species. This species is in the subgenus Cerastes, and, 
like all members of this subgenus, it is an obligate seeding species 
and does not have a burl (an underground mass from which the species 
can resprout following fire). Therefore, this species requires fire to 
establish new seedlings. However, if fire burns too frequently there is 
insufficient time for the plant to mature and establish a seed bank, 
placing populations at risk of extirpation (Keeley 2006, p. 367). The 
natural fire regime for the chaparral ecosystem is once every 20 to 50 
years. Little information exists regarding the dispersal of this 
species.

Primary Constituent Elements for Ceanothus ophiochilus

    Pursuant to the Act and its implementing regulations, we are 
required to identify the known physical or biological features (PCEs) 
within the geographical area occupied at the time of listing that are 
essential to the conservation of Ceanothus ophiochilus, which may 
require special management considerations or protection. All areas 
designated as critical habitat for C. ophiochilus are occupied, within 
the species' historical geographic range, and contain sufficient PCEs 
to support at least one life history function.
    Based on our current knowledge of the life history, biology, and 
ecology of the species and the requirements of the habitat to sustain 
the essential life history functions of the species, we have determined 
the PCEs for Ceanothus ophiochilus are:
    (1) Flat to gently sloping north to northeast facing ridge tops 
with slopes in the range of 0 to 40 percent slope that provide the 
appropriate solar exposure for seedling establishment and growth;
    (2) Soils formed from metavolcanic and ultra-basic parent materials 
and deeply weathered gabbro or pyroxenite-rich outcrops that provide 
nutrients and space for growth and reproduction. Specifically in the 
areas that Ceanothus ophiochilus is found, the soils are:
    (a) Ramona, Cienaba, Las Posas, and Vista series in the Agua Tibia 
Wilderness; and
    (b) Cajalco series in the vicinity of Vail Lake; and
    (3) Chamise chaparral or mixed chamise-ceanothus-arctostaphylos 
chaparral at elevations of 2,000 ft to 3,000 ft (610 m to 914 m) that 
provide the appropriate canopy cover and elevation requirements for 
growth and reproduction.

Fremontodendron mexicanum

    The specific primary constituent elements required for 
Fremontodendron mexicanum are derived from the biological and physical 
needs of the species as described in the final listing rule (63 FR 
54956, October 13, 1998), the pr