Endangered and Threatened Wildlife and Plants; Revised Designation of Critical Habitat for Cirsium loncholepis (La Graciosa Thistle), 45806-45846 [E8-17808]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 73, Number 152 (Wednesday, August 6, 2008)]
[Proposed Rules]
[Pages 45806-45846]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E8-17808]



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Part II





Department of the Interior





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Fish and Wildlife Service



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50 CFR Part 17



Endangered and Threatened Wildlife and Plants; Revised Designation of 
Critical Habitat for Cirsium loncholepis (La Graciosa Thistle); 
Proposed Rule

Federal Register / Vol. 73, No. 152 / Wednesday, August 6, 2008 / 
Proposed Rules

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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

[FWS-R8-ES-2008-0078; 99210-1117-0000-B4]

50 CFR Part 17

RIN 1018-AV03


Endangered and Threatened Wildlife and Plants; Revised 
Designation of Critical Habitat for Cirsium loncholepis (La Graciosa 
Thistle)

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), propose to 
revise the currently designated critical habitat for Cirsium 
loncholepis (La Graciosa thistle) pursuant to the Endangered Species 
Act of 1973, as amended (Act). In total, approximately 38,447 acres 
(ac) (15,559 hectares (ha)) fall within the boundaries of this proposed 
revised critical habitat designation. The proposed revision is to 
critical habitat located in San Luis Obispo and Santa Barbara Counties, 
California.

DATES: We will accept comments from all interested parties until 
October 6, 2008. We must receive requests for public hearings, in 
writing, at the address shown in the ADDRESSES section by September 22, 
2008.

ADDRESSES: You may submit comments by one of the following methods:
     Federal eRulemaking Portal: https://www.regulations.gov. 
Follow the instructions for submitting comments.
     U.S. mail or hand-delivery: Public Comments Processing, 
Attn: [FWS-R8-ES-2008-0078]; Division of Policy and Directives 
Management; U.S. Fish and Wildlife Service; 4401 N. Fairfax Drive, 
Suite 222; Arlington, VA 22203.
    We will not accept e-mail or faxes. We will post all comments on 
https://www.regulations.gov. This generally means that we will post any 
personal information you provide us (see the Public Comments section 
below for more information).

FOR FURTHER INFORMATION CONTACT: Diane K. Noda, Field Supervisor, 
Ventura Fish and Wildlife Office, 2493 Portola Road, Suite B, Ventura, 
California, 93003 (telephone 805/644-1766; facsimile 805/644-3958). If 
you use a telecommunications device for the deaf (TDD), call the 
Federal Information Relay Service (FIRS) at 800-877-8339.

SUPPLEMENTARY INFORMATION:

Public Comments Solicited

    We intend any final action resulting from this proposal to be as 
accurate and as effective as possible. Therefore, we request comments 
or suggestions on this proposed rule. We particularly seek comments 
concerning:
    (1) The reasons why we should or should not revise the designation 
of habitat as ``critical habitat'' under section 4 of the Act (16 
U.S.C. 1531 et seq.), including whether the benefit of designation 
would outweigh threats to the species caused by the designation, such 
that the designation of critical habitat is prudent;
    (2) Specific information on:
     The amount and distribution of Cirsium loncholepis 
habitat,
     The importance of including habitat that provides 
connectivity between extant populations of C. loncholepis to the 
species' conservation and recovery, and the amount and distribution of 
such habitat;
     Which areas within the geographical area occupied at the 
time of listing that contain features essential to the conservation of 
the species we should include in the designation and why, and
     Which areas not within the geographical area occupied at 
the time of listing that are essential for the conservation of the 
species and why;
    (3) Land use designations and current or planned activities in the 
subject areas and their possible impacts on proposed critical habitat;
    (4) Any foreseeable economic, national security, or other relevant 
impacts resulting from the proposed revised designation, and, in 
particular, any impacts on small entities, and the benefits of 
including or excluding areas that exhibit these impacts;
    (5) This proposed designation's revised criteria for determining 
essential features and critical habitat boundaries; and
    (6) The existence of any conservation or management plans being 
implemented by California State Parks, Oceano Dunes State Vehicular 
Recreation Area; Vandenberg Air Force Base; County of Santa Barbara, 
Rancho Guadalupe Dunes County Park; Guadalupe-Nipomo Dunes National 
Wildlife Refuge; or other public or private land management agencies or 
owners that we should consider for exclusion from the designation 
pursuant to section 4(b)(2) of the Act. Please include information on 
any benefits (educational, regulatory, etc.) of including or excluding 
lands from this proposed revised designation.
    (7) Whether we could improve or modify our approach to designating 
critical habitat in any way to provide for greater public participation 
and understanding, or to better accommodate public concerns and 
comments;
    (8) Whether there are areas that were previously designated as 
critical habitat that we are now removing from designation in this 
proposed rule, that should remain as critical habitat in the rule.
    You may submit your comments and materials concerning this proposed 
rule by one of the methods listed in the ADDRESSES section. We will not 
consider comments sent by e-mail or fax or to an address not listed in 
the ADDRESSES section.
    If you submit a comment via http: //www.regulations.gov, your 
entire comment--including any personal identifying information--will be 
posted on the Web site. If you submit a hardcopy comment that includes 
personal identifying information, you may request at the top of your 
document that we withhold this information from public review. However, 
we cannot guarantee that we will be able to do so. We will post all 
hardcopy comments on https://www.regulations.gov.

Background

    It is our intent to discuss only those topics directly relevant to 
this proposed revised designation of critical habitat. Additional 
background information covering the general ecology of Cirsium 
loncholepis was published in the final listing rule on March 20, 2000 
(65 Federal Register (FR) 14888), the proposed rule to designate 
critical habitat published on March 30, 1998 (63 FR 15164), and the 
final designation of critical habitat for C. loncholepis on March 17, 
2004 (69 FR 12553).

Species Description and Reproduction

    Cirsium loncholepis is a biennial to short-lived monocarpic 
perennial (a plant that blooms once, then dies) (Hendrickson 1990, pp. 
20-22; Teed 2003, p. 1). It is a spreading, mound-like or erect plant 
in the Asteraceae (sunflower family) that is well armored with spines 
on the leaves and flower heads. The plants range from 4 to 39 
(occasionally up to 59) inches (in) (10 to 100 (occasionally up to 150) 
centimeters (cm)) tall, with one or more stems. The lower leaves are 4 
to 12 in (10 to 30 cm) long, with spiny petioles (leaf stalks), and are 
usually deeply lobed with secondary lobes or teeth. The leaves are 
wavy-margined. The leaf bases of the middle and upper leaves form 
short, spiny wings along the petiole. Flowering heads are 0.8 to 1.6 in 
(2 to 4 cm) wide in tight clusters at the tips

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of the stems. The corollas (flowers) are 1 to 1.2 in (25 to 30 
millimeters (mm)) long and are nearly white with a purplish tube 
containing purple anthers. The achenes (fruit) are 0.01 to 0.02 in (3 
to 4 mm) long and topped by an umbrella of long awns (0.6 to 1.0 in (15 
to 25 mm)) that are ideal for wind dispersal (Keil and Turner 1993, pp. 
232-239). Large individuals produce more flowering heads and more seeds 
per head (average = 473 seeds per plant) than smaller individuals 
(average = 168 seeds per plant), and therefore contribute 
disproportionately to the future seedbank of the population (Lea 2001a, 
unpaginated).

Taxonomy

    In 2006, Dr. David Keil revised the treatment for the genus Cirsium 
in North America for the Flora of North America north of Mexico by 
taking a broad view of the genus and the overlap in ranges of variation 
in morphologic characters (visible plant characteristics) (Keil 2006a, 
pp. 1, 57, 66, 82, 83, 93, 95-160). Dr. Keil synonymized (lumped) C. 
loncholepis with C. scariosum var. citrinum (La Graciosa thistle, same 
common name as the listed entity), a more widespread taxon whose 
distribution encompasses the following areas: The distribution of the 
C. loncholepis, at the mouth of the Santa Maria River; C. scariosum 
populations in the San Emigdio Mountains (Kern and Ventura Counties); 
and C. scariosum populations in the uplands and lowlands of the 
Peninsular Ranges of southern California (Riverside and San Diego 
Counties) that continue down into northern Baja California, Mexico 
(Keil 2006a, pp. 1, 57, 66, 82, 83, 93, 95-160). Dr. Keil has since 
informed us that he is re-recognizing C. loncholepis as a distinct 
entity as a subtaxon of C. scariosum and that he will publish it in a 
journal article and in the upcoming second edition of The Jepson 
Manual: Higher Plants of California. (Keil 2007a, unpaginated; 2007b, 
unpaginated). We consider this to be the best available scientific and 
commercial information. Accordingly, we continue to recognize C. 
loncholepis as a distinct entity.

Distribution

    Below, we define various terms that are used for different 
assemblages of plants that we use in discussing the status of Cirsium 
loncholepis. In this rule we use the term ``occurrence'' to be 
consistent with the definition used by the California Natural Diversity 
Database (CNDDB): A grouping of plants within 0.25 mile (mi) (0.4 
kilometer (km)) of each other (CNDDB 2007, unpaginated). There may be 
(and occasionally are) one or more discrete polygons of plants within a 
single ``occurrence.'' We use the term ``population'' to refer to a 
group of interbreeding individuals, in the biological sense of the 
word. There may be (and usually are) one or more ``occurrences'' within 
a single population. Our use of the term ``location'' in previous rules 
for C. loncholepis was interchangeable with ``occurrence'' and 
``population.'' In this rule ``location'' refers only to a particular 
site, area, or region, as in ``at that location,'' with no relation to 
an assemblage of plants (e.g., polygon, occurrence, population). The 
terms ``site,'' ``area,'' and ``region'' refer to physical places.
    Cirsium loncholepis historically was found in mesic areas (areas 
with intermediate or medium moisture conditions that are neither very 
wet nor very dry) in back dune and coastal wetlands along a 32-mi (52-
km) stretch of the coastal region of central California between Arroyo 
Grande Creek in San Luis Obispo County to the north and the Santa Ynez 
River in Santa Barbara County to the south. In this range, it occurred 
up to 16 mi (26 km) inland where it was documented at the Ca[ntilde]ada 
de las Flores area on the south side of the Solomon Hills. Most of the 
known occurrences are associated with mesic sites in two dune complexes 
(the Santa Maria Valley Dune Complex and the Santa Ynez Valley Dune 
Complex) and along the drainages and tributaries of four major 
watersheds in this area (from north to south: Arroyo Grande Creek, 
Santa Maria River, San Antonio Creek, and Santa Ynez River).
    Historically, Cirsium loncholepis has been reported or documented 
from a total of 25 occurrences that are grouped among 11 populations 
ranging from the dunes near Pismo Beach inland to hillside seeps at 
Ca[ntilde]ada de las Flores south to the floodplains of the Santa Ynez 
River (CNDDB 2007, unpaginated; Consortium of California Herbaria 2008, 
unpaginated). These 11 populations are: Oceano, northern Callender Dune 
Lakes, southern Callender Dune Lakes, Oso Flaco, southern Guadalupe 
Dunes, Santa Maria River, Guadalupe, La Graciosa (type locality--the 
geographical location for the collection of the type specimen or the 
specimen that fixes a name to a species), Ca[ntilde]ada de las Flores, 
San Antonio Terrace, and Santa Ynez River. See: 63 FR 15164, March 30, 
1998; 65 FR 14888, March 20, 2000; 66 FR 57560, November 15, 2001; and 
69 FR 12553, March 17, 2004; and Hendrickson (1990, pp. 1-25) for more 
in-depth discussions on the historical habitats, distribution, and 
range of C. loncholepis.
    At the time of the listing in 2000, there were 17 recorded 
occurrences. After reviewing the historical records, we determined that 
11 of the 17 occurrences were extant (still in existence). These 11 
extant occurrences were distributed among 7 populations. At the time of 
listing, the extant occurrences ranged from the northern Callender Dune 
Lakes in the Callender Dunes in the north to the seeps at Ca[ntilde]ada 
de las Flores in the south (65 FR 14888, March 20, 2000; CNDDB 1998, 
unpaginated). Since the time of listing, Cirsium loncholepis has 
experienced considerable declines throughout its range. Currently, C. 
loncholepis is considered to be extant at seven occurrences that are 
distributed among four populations: Southern Callender Dune Lakes, Oso 
Flaco, southern Guadalupe Dunes, and Santa Maria River. The seven 
extant occurrences consist of five occurrences that were identified in 
the final listing rule in 2000 as well as two new occurrences that have 
been identified since that time (CNDDB 2007, unpaginated; Elvin 2006, 
unpaginated, 2007a, unpaginated). The extant occurrences currently 
range from the southern Callender Dune Lakes in the north to the Santa 
Maria River in the south. See Figure 1 for the current versus 
historical distribution of C. loncholepis. The points in this figure 
represent locations of polygons of C. loncholepis plants. Some C. 
loncholepis occurrences contain more than one polygon.
BILLING CODE 4310-55-P

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[GRAPHIC] [TIFF OMITTED] TP06AU08.000

    The Service has reviewed the most current information regarding 
occupancy at Cirsium loncholepis historically known to have been 
occupied, or occupied at time of listing. Cirsium loncholepis may still 
be extant

[[Page 45809]]

at Ca[ntilde]ada de las Flores. It was last observed at this site in 
1989 (Hendrickson 1990, pp. 1-25). Based on this information at the 
time of listing, we considered Ca[ntilde]ada de las Flores to be 
occupied. Since the time of listing, there have still been no 
observations of C. loncholepis at Canada de las Flores. No plants were 
observed during surveys in 1990 (Hendrickson 1990, pp. 1-25), and no 
plants were observed by Mark A. Elvin and Jeanette Sainz when they 
visited the site in November 2007. This visit was conducted outside the 
optimal time of year to observe this plant in a dry year, and it was 
not an exhaustive survey (Elvin 2007b, unpaginated). While C. 
loncholepis may still be at Canada de las Flores, we are considering 
Ca[ntilde]ada de las Flores to be unoccupied for the purposes of this 
rule based on the continued lack of observation of C. loncholepis since 
2000. Cirsium loncholepis has not been observed at the northern 
Callender Dune Lakes population (in the dunes just south of Pismo Beach 
and Oceano) since 1988, but no surveys have been conducted here since 
1988 to our knowledge. Cirsium loncholepis may still be extant at this 
population. Cirsium loncholepis has not been observed at the Santa Ynez 
River population since 1958 (CNDDB 2007, unpaginated; Consortium of 
California Herbaria 2008, unpaginated; Smith 1976, p. 282, 1998, pp. 
153-154; Santa Barbara Botanical Garden Herbarium 2007, unpaginated). 
Surveys were conducted by the Biological Sciences Department at 
California Polytechnic State University between 1992 and 1994, but no 
plants were found (Keil and Holland 1998, pp. 83-84); no other surveys 
are known to have been conducted. Therefore, C. loncholepis is not 
currently known to occur along the Santa Ynez River. San Antonio 
Terrace is centrally located within the range of C. loncholepis. It is 
south of the Guadalupe and Callender Dune Sheets and the Santa Maria 
River, west of Canada de las Flores, and north of the Santa Ynez River. 
San Antonio Terrace supports numerous dune wetlands and swales and has 
the same physical and geological features, habitats, and vegetation as 
the Callender and Guadalupe Dune Sheets (Hunt 1993, pp. 5-72; CNDDB 
2007, unpaginated; Consortium of California Herbaria 2008, unpaginated; 
Google Earth 2008, unpaginated). Cirsium loncholepis is reported from 
the dune swales on San Antonio Terrace, but it has never been 
documented here with a voucher specimen (CNDDB 2007, unpaginated; 
Henningson et al. 1980, pp. 15-120; Consortium of California Herbaria 
2008, unpaginated). San Antonio Terrace is directly adjacent to the 
mouth of San Antonio Creek which, according to some researchers, is the 
most likely site for the type locality for C. loncholepis (Keil and 
Holland 1998, pp. 83-84; Oyler et al. 1995, pp. 1-76; Hendrickson 1990, 
pp. 1-25; Smith 1976, p. 282, 1998, pp. 153-154). The type locality is 
the geographical location for the collection of the type specimen or 
the specimen that fixes a name to a species. In the case of C. 
loncholepis, we do not know the exact location of the type locality of 
``La Graciosa''. There is a consensus among researchers that La 
Graciosa was at one of two places, one of which is the mouth of San 
Antonio Creek and the other along Orcutt Creek (see the final listing 
rule for a discussion on this location). Cirsium brevistylum has been 
documented at San Antonio Terrace. Some researchers speculate that the 
reports of C. loncholepis from the San Antonio Terrace population were 
pre-flowering C. brevistylum plants, which are very similar to pre-
flowering C. loncholepis plants (CNDDB 2007, unpaginated; Consortium of 
California Herbaria 2008, unpaginated; Hendrickson 1990, pp. 1-25; Keil 
and Holland 1998, p. 82).
    In addition to the apparent loss of occurrences and populations, 
there has been a decline in the status of the species and the number of 
individuals reported at the remaining extant sites identified in the 
listing rule (Chesnut 1998a, unpaginated; Chesnut 1998b, pp. 1-40; 
Hendrickson 1990, pp. 1-25; CNDDB 2007, unpaginated). Most notably, 
Service staff visited the western portion of the Santa Maria River 
population in November 2006, and fewer than 10 individuals were 
observed (Elvin 2006, unpaginated). While this was outside the optimal 
time of year, Cirsium loncholepis was fruiting and observable. This 
population (which includes two occurrences) was estimated to contain 
6,000 individuals in 1986 (CNDDB 2007, unpaginated), more than 50,000 
individuals in 1990 (Hendrickson 1990, pp. 1-25), and 500 individuals 
in the western portion in 2001 (CNDDB 2007, unpaginated). Specific 
survey conditions are not known for these reports. Reports also 
indicate declines in status and numbers of individuals at the northern 
Guadalupe Dunes population with estimates in the 25-50 range for the 
1980s and early 1990s down to 7 individuals in 1998 (Chesnut 1998a, 
unpaginated; Chesnut 1998b, pp. 1-40; Hendrickson 1990, pp. 1-25; CNDDB 
2007, unpaginated). Reports for the southern Guadalupe Dunes population 
have been fluctuating between 30 and 137 individuals with Service staff 
noting greater than 50 individuals in November of 2006 (CNDDB 2007, 
unpaginated; Elvin 2006, unpaginated; Hendrickson 1990, pp. 1-25).
    In summary, Cirsium loncholepis may not currently be present at the 
Oceano, northern Callender Dune Lakes, Guadalupe, La Graciosa, 
Ca[ntilde]ada de las Flores, San Antonio Terrace, and Santa Ynez River 
populations. This species has declined from 11 extant occurrences 
identified at the time of listing to 7 remaining extant occurrences (in 
4 populations). The seven extant occurrences consist of five 
occurrences that were identified in the final listing rule in 2000 as 
well as two new occurrences that have been identified since that time. 
We believe that C. loncholepis may not persist if the Santa Maria 
Valley Dune Complex occurrences (including those along the Santa Maria 
River) are the only ones remaining. However, we believe that C. 
loncholepis could be conserved and recovered if additional populations 
exist or new populations arise in habitat with features (described 
below) that allow the populations to remain connected throughout the 
two dune complexes and four major watersheds where it once was known to 
occur.

Previous Federal Actions

    A proposed rule to list Cirsium loncholepis and three other species 
as endangered was published on March 30, 1998 (63 FR 15164). Cirsium 
loncholepis was listed as endangered under the Act in 2000 due to 
threats from groundwater pumping, oil field development, oil field 
remediation, competition from non-native plants, and grazing from 
cattle (Hendrickson 1990, pp. 1-25; California Department of Fish and 
Game (CDFG) 1992, pp. 111-112; 65 FR 14888, March 20, 2000). The State 
of California listed this species as threatened in 1990 (CDFG 1992, pp. 
111-112). The proposed rule to designate critical habitat for C. 
loncholepis and two other species was published in the Federal Register 
on November 15, 2001 (66 FR 57560). In August 2002, we received a 1-
year extension beyond the statutory time limit on the publication date 
of a final rule for C. loncholepis critical habitat due to its 
taxonomic uncertainty. In September 2003, we sought an additional 
extension due, in part, to the continued uncertainty regarding its 
taxonomic status, but the court denied that request. We published a 
final rule designating critical habitat for C. loncholepis on March 17, 
2004 (69 FR 12553), in compliance with the court's order. Please refer 
to the final listing

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rule published in the Federal Register on March 20, 2000 (65 FR 14888), 
and to the final designation of critical habitat published on March 17, 
2004 (69 FR 12553), for additional or more complete information on 
previous Federal actions prior to that time. In the 2004 final critical 
habitat rule we designated approximately 41,089 acres (ac) (16,628 
hectares (ha)) of land in San Luis Obispo and Santa Barbara Counties, 
California, as critical habitat for C. loncholepis. The final critical 
habitat rule also contains information regarding the litigation history 
related to the listing and designation of critical habitat for this 
species (Southwest Center for Biological Diversity, et al. v. U.S. Fish 
and Wildlife Service et al. (No. C99-2992 (N.D.Ca.)).
    On March 30, 2005, the Homebuilders Association of Northern 
California, et al., filed a complaint against the Service (Home 
Builders Association of N. Cal., et al. v. U.S. Fish and Wildlife 
Service, et al., No. 2:05-01363, E.D. Cal.) alleging that the final 
rule designating critical habitat for Cirsium loncholepis (and 26 other 
species) violated the Act, the Administrative Procedure Act, and the 
National Environmental Policy Act. In March 2006, a settlement was 
reached to re-evaluate five final critical habitat designations, which 
included the 2004 critical habitat designation for C. loncholepis. The 
settlement stipulated that proposed revisions to the C. loncholepis 
designation would be submitted to the Federal Register on or before 
July 27, 2007. On May 17, 2007, the court approved a modification to 
the settlement timeframe to require that a proposed rule regarding any 
revisions to the C. loncholepis critical habitat designation would be 
submitted to the Federal Register on or before July 27, 2008, and a 
final decision regarding any proposed rule would be submitted on or 
before July 27, 2009. This revised proposed rule complies with the May 
17, 2007, court order.

Critical Habitat

    Critical habitat is defined in section 3 of the Act as:
    (1) The specific areas within the geographical area occupied by a 
species, at the time it is listed in accordance with the Act, on which 
are found those physical or biological features
    (a) essential to the conservation of the species and
    (b) which may require special management considerations or 
protection; and
    (2) Specific areas outside the geographical area occupied by a 
species at the time it is listed, upon a determination that such areas 
are essential for the conservation of the species.
    Conservation, as defined under section 3 of the Act, means the use 
of all methods and procedures that are necessary to bring any 
endangered species or threatened species to the point at which the 
measures provided under the Act are no longer necessary.
    Critical habitat receives protection under section 7 of the Act 
through the prohibition against Federal agencies carrying out, funding, 
or authorizing the destruction or adverse modification of critical 
habitat. Section 7 of the Act requires consultation on Federal actions 
that may affect critical habitat. The designation of critical habitat 
does not affect land ownership or establish a refuge, wilderness, 
reserve, preserve, or other conservation area. Such designation does 
not allow the government or public to access private lands. Such 
designation does not require implementation of restoration, recovery, 
or enhancement measures by the landowner. Where the landowner seeks or 
requests federal agency funding or authorization that may affect a 
listed species or critical habitat, the consultation requirements of 
section 7 would apply, but even in the event of a destruction or 
adverse modification finding, the landowner's obligation is not to 
restore or recover the species, but to implement reasonable and prudent 
alternatives to avoid destruction or adverse modification of critical 
habitat.
    For inclusion in a critical habitat designation, habitat within the 
geographical area occupied by the species at the time it was listed 
must contain features that are essential to the conservation of the 
species. Critical habitat designations identify, to the extent known 
using the best scientific data available, habitat areas that provide 
essential life cycle needs of the species (areas on which are found the 
primary constituent elements, as defined at 50 CFR 424.12(b)). Occupied 
habitat that contains the features essential to the conservation of the 
species meets the definition of critical habitat only if those features 
may require special management considerations or protection. Under the 
Act, we can designate critical habitat in areas outside the 
geographical area occupied by the species at the time it is listed only 
when we determine that those areas are essential for the conservation 
of the species.
    Section 4 of the Act requires that we designate critical habitat on 
the basis of the best scientific and commercial data available. 
Further, our Policy on Information Standards Under the Endangered 
Species Act (published in the Federal Register on July 1, 1994 (59 FR 
34271)), the Information Quality Act (section 515 of the Treasury and 
General Government Appropriations Act for Fiscal Year 2001 (Pub. L. 
106-554; H.R. 5658)), and our associated Information Quality 
Guidelines, provide criteria, establish procedures, and provide 
guidance to ensure that our decisions are based on the best scientific 
data available. They require our biologists, to the extent consistent 
with the Act and with the use of the best scientific data available, to 
use primary and original sources of information as the basis for 
recommendations to designate critical habitat.
    When we are determining which areas should be proposed as critical 
habitat, our primary source of information is generally the information 
developed during the listing process for the species. Additional 
information sources 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.
    Habitat is often dynamic, and species may move from one area to 
another over time. Furthermore, we recognize that critical habitat 
designated at a particular point in time may not include all of the 
habitat areas that we may eventually determine, based on scientific 
data not now available to the Service, are necessary for the recovery 
of the species. For these reasons, a critical habitat designation does 
not signal that habitat outside the designated area is unimportant or 
may not be required for recovery of the species.
    Areas that support populations, but are outside the critical 
habitat designation, will continue to be subject to conservation 
actions we implement under section 7(a)(1) of the Act. They are also 
subject to the regulatory protections afforded by the section 7(a)(2) 
jeopardy standard, as determined on the basis of the best available 
scientific information at the time of the agency action. Federally 
funded or permitted projects affecting listed species outside their 
designated critical habitat areas may still result in jeopardy findings 
in some cases. Similarly, critical habitat designations made on the 
basis of the best available information at the time of designation will 
not control the direction and substance of future recovery plans, 
habitat conservation plans (HCPs), or other species conservation 
planning efforts if new information available to these planning efforts 
calls for a different outcome.

[[Page 45811]]

Methods

    As required by section 4(b) of the Act, we used the best scientific 
and commercial data available in determining specific areas within the 
geographical area occupied at the time of listing that contain physical 
or biological features essential to the conservation of Cirsium 
loncholepis and specific areas outside the geographical area occupied 
at the time of listing that are essential for the conservation C. 
loncholepis. This includes information from the final listing rule in 
2000 and final critical habitat designation in 2004; data from research 
and survey observations published in peer-reviewed articles; data from 
research and survey observations included in reports and other 
manuscripts (i.e., theses, monitoring reports); written and oral 
communications from species and other physical science experts; reports 
and survey forms prepared for Federal, State, and local agencies, and 
private corporations; regional Geographic Information System layers, 
including soil, species, aerial imagery, and wetlands coverages; 
information from herbarium specimens at the following institutions: 
University of California Santa Barbara Herbarium, University of 
California Berkeley Herbarium, the Jepson Herbarium at the University 
of California Berkeley, University of Minnesota Saint Paul Herbarium, 
Rancho Santa Ana Botanic Garden Herbarium, Herbarium of the California 
Academy of Sciences, California Department of Food and Agriculture 
Herbarium, Santa Barbara Botanical Garden Herbarium, San Diego Natural 
History Museum Herbarium, Robert F. Hoover Herbarium at California 
Polytechnic State University San Luis Obispo, University of California 
Riverside Herbarium, and University of California Irvine Herbarium; 
site visits by Service biologists to several population sites of C. 
loncholepis in 2006 and 2007; and data submitted to the CNDDB. We have 
also reviewed available information that pertains to the ecology, life 
history, and habitat requirements for this species. This material 
included information and data in peer-reviewed articles; reports of 
monitoring and habitat characterizations; reports submitted during 
section 7 consultations; and information received from local species 
experts.

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 within the geographical area 
occupied at the time of listing to propose as critical habitat, we 
consider the physical and biological features that are essential to the 
conservation of the species to be the primary constituent elements 
(PCEs) laid out in the appropriate quantity and spatial arrangement for 
conservation of the species. These include, but are not limited to:
    (1) Space for individual and population growth and for normal 
behavior;
    (2) Food, water, air, light, minerals, or other nutritional or 
physiological requirements;
    (3) Cover or shelter;
    (4) Sites for breeding, reproduction, rearing, or development of 
offspring; and
    (5) Habitats that are protected from disturbance or are 
representative of the historical, geographical, and ecological 
distributions of a species.
    We derive the specific PCEs required for the Cirsium loncholepis 
from its biological needs.

Space for Individual and Population Growth

    Cirsium loncholepis generally grows in association with mesic areas 
on the margins of dune swales, dune lakes, marshes, estuaries, coastal 
meadows, seeps, springs, intermittent streams, creeks, and rivers 
(CNDDB 2007, unpaginated; Consortium of California Herbaria 2008, 
unpaginated; Elvin 2006, unpaginated, 2007a, unpaginated, 2007b, 
unpaginated). Cirsium loncholepis occurs in a series of dynamic systems 
of dunes and riparian floodplains. Cirsium loncholepis can appear and 
disappear from particular sites appearing to ``move'' from place to 
place in areas with suitable habitat on a fairly regular basis (this 
has been observed several times over the past 50 or more years (CNDDB 
2007, unpaginated; Chesnut 1998a, unpaginated; Hendrickson 1990, pp. 1-
25)). New suitable sites are continuously created throughout the 
dynamic ecosystems where C. loncholepis grows over time (i.e., floods 
remove vegetation and create new sites; dunes move and suitable sites 
open up). The conservation of C. loncholepis depends not only on 
maintaining suitable sites for germination and growth as they exist at 
the present, but it also depends on maintaining the dynamic nature of 
the habitat (the dune and riparian complexes) where it grows, which 
will ensure that suitable sites for germination and growth will develop 
in the future.

Nutritional and Physiological Requirements Including Soils, 
Communities, and Dispersal

Soils
    Soils where Cirsium loncholepis are found are somewhat variable, 
but include a large component of sand. Coastal populations occur on 
dune sands, Oceano sands, Camarillo sandy loams, riverwash, and sandy 
alluvial soils at elevations of less than 31 meters (m) (100 feet (ft)) 
(Hendrickson 1990, pp. 1-25; CNDDB 2001, unpaginated, 2007, 
unpaginated). Occasionally, individuals have been found on dune slopes 
or ridges, rather than in the more typical dune swale habitat; more 
stable dunes have been shown to act as reservoirs of moisture, and 
these individuals may be tapping into this moisture (Thomas 2001, 
unpaginated). Plants at an inland population have been found on 
Camarillo sandy loam at an elevation of 183 m (600 ft) (CNDDB 2001, 
unpaginated).
Communities
    The vegetation communities associated with Cirsium loncholepis are 
rather diverse and include central dune scrub, coastal dune, coastal 
scrub, freshwater seeps and springs, coastal and valley freshwater 
marsh and fen, riparian scrub (e.g., mule fat scrub, willow scrub), 
riparian forest, chaparral, oak woodland, intermittent streams, and 
other wetland communities (Hendrickson 1990, pp. 1-25; CNDDB 2007, 
unpaginated). Cirsium loncholepis is often growing in and amongst a mat 
of low-growing, herbaceous, wetland plants including Juncus spp. 
(rush), Scirpus spp. (tule), Carex praegracilis (sedge), Distichlis 
spicata (salt grass), Cynodon dactylon (Bermuda grass), Trifolium 
wormskioldii (clover), Anemopsis californica (yerba mansa), Potentilla 
anserina (silverweed), and Lotus corniculatus (birdfoot trefoil) 
(Langford 2001, unpaginated; CNDDB 2007, unpaginated; Chesnut 1998b, 
pp. 1-40; Elvin 2006, unpaginated, 2007a, unpaginated; Reed 1988, pp. 
15-51). Other closely associated riparian plants include Salix spp. 
(willow), Rubus (blackberry), and Baccharis douglasii (Douglas' 
baccharis) (CNDDB 2007, unpaginated; Chesnut 1998b, pp. 1-40; Elvin 
2006, unpaginated, 2007a, unpaginated, 2007b, unpaginated; Reed 1988, 
pp. 15-51). Upland plants that occur adjacent to or nearby include 
Toxicodendron diversilobum (poison oak), Baccharis pilularis (coyote 
brush), Solidago californica (California goldenrod), Isocoma menziesii 
(coast goldenbush), and Corethrogyne filaginifolia (California aster)

[[Page 45812]]

(Hendrickson 1990, pp. 1-25; CNDDB 2007, unpaginated; Elvin 2006, 
unpaginated, 2007a, unpaginated, 2007b, unpaginated). Plants at the 
most inland site for Cirsium loncholepis have been found primarily 
around gently sloping hillside seeps within a grassland community, at 
the edge of willows around a seep bordering an oak woodland community 
(Hendrickson 1990, pp. 1-25, Elvin 2007b, unpaginated). Cirsium 
loncholepis does occasionally occur in non-mesic conditions such as on 
ridges or dune tops such as in the Guadalupe Dunes (Elvin 2006, 
unpaginated) or throughout meadows (temporally and spatially) on flat 
valley bottoms, which are rather dry compared to the mesic seeps in 
these area (Elvin 2007b, unpaginated).
Dispersal
    Genetic material can move both within a population or between 
different populations. In plants this can be accomplished through the 
movement of pollen, seeds, plants, or plant parts to other plants or 
sites within the same population or to another population. For Cirsium 
loncholepis, the main agents for gene flow are pollen and seeds. 
Pollinators move pollen from one flower to another. Most pollinators 
move pollen within the same population, but it can be moved to another 
population if it is close enough and the pollinator is capable of 
moving the pollen across that distance. Cirsium loncholepis seeds are 
capable of being moved within the same population and to another 
population by animals, wind, and water.
    Pollinators: Cirsium loncholepis is capable of both self-
fertilization (pollination events on the same individual) and cross-
fertilization (pollination events between two individuals). Other 
similar, riparian, monocarpic Cirsium species self- and cross-pollinate 
(Hamzo and Jolls 2000, pp. 141-153). Cirsium loncholepis flowers 
produce nectar and copious quantities of pollen and are visited by 
birds and a wide variety of insects (Keil 2008, unpaginated). Cirsium 
loncholepis and other Cirsium taxa with similar heads are pollinated by 
bees (i.e., solitary, mining, (families Andrenidae and Anthophoridae), 
mason (Osmia sp.), carpenter (Xylocopa sp.), and leaf cutter bees 
(family Megachilidae) and the introduced honeybee (Apis mellifera)), 
butterflies (order Lepidoptera), flies (order Diptera), beetles (order 
Coleoptera (e.g., darkling ground beetles (family Tenebrionidae))), 
black ants (family Formicidae), and hummingbirds (family Trochilidae) 
(Keil 2001, unpaginated, 2008, unpaginated; Moldenke 1976, pp. 305-361; 
Krombein et al. 1979, Vol. 2, pp. 1751-2209; Lea. 2001b, unpaginated). 
Specialist-feeding bees (solitary bees, which are known to visit 
Cirsium species (Krombein et al. 1979, Vol. 2 pp. 1751-2209)) commonly 
develop co-evolutionary relationships with particular host plants 
(Moldenke 1976, pp. 305-361). While we do not have comprehensive 
information on the home ranges and species fidelity of these 
pollinators, we do have some data. A number of the insects noted above 
that are known to visit Cirsium flowers (i.e., ants, some beetles, 
butterflies, flies, and many bee taxa) live, nest, and reproduce in 
upland habitats (e.g., coastal dune scrub, coastal scrub, chaparral, 
oak woodland, grassland) within the range of C. loncholepis (Moldenke 
1976, pp. 305-361; Hogue 1993, 446 pp.; Krombein et al. 1979, Vol. 2 
pp. 1751-2209; Thorp et al. 1983, pp. 1-79). Alternative pollen source 
plants may be necessary for the persistence of these insects when C. 
loncholepis is not in flower seasonally or annually because of poor 
environmental conditions.
    The main dispersal vectors for Cirsium loncholepis pollen include 
ants, beetles, butterflies, flies, bees, and hummingbirds. Some of 
these visitors (e.g., bumble bees, hummingbirds) can fly large 
distances and are therefore capable of transferring pollen longer 
distances, from plants in one population to plants in another 
population. Studies to quantify the distance that bees will fly to 
pollinate their host plants are limited in number, but the few that 
exist show that some bees will routinely fly from 328 to 984 ft (100 to 
500 m) to pollinate plants (Thorp and Leong 1995, pp. 3-7; Schulke and 
Waser 2001, pp. 239-245). In a study of experimental isolation and 
pollen dispersal of Delphinium nuttallianum (Nuttall's larkspur), 
Schulke and Waser (2001, pp. 239-245) report that adequate pollen loads 
were dispersed by bumblebees within control populations and in isolated 
experimental ``populations'' from 328 to 1,312 ft (100 m to 400 m) 
distant from the control populations. One of the several pollinator 
taxa effective at 1,312 ft (400 m) was Bombus (bumblebee), which has 
also been documented to visit Cirsium (Ascher 2006, unpaginated). 
Studies by Steffan-Dewenter and Tscharntke (2000, pp. 288-296) 
demonstrated that it is possible for bees to fly as far as 3,280 ft 
(1,000 m) to pollinate flowers, and at least one study suggests that 
bumblebees may forage many kilometers from a colony (Sugden 1985, pp. 
299-312). Hummingbirds can fly long distances while foraging for nectar 
or food or migrating. Using area rather than distance, an Anna's 
hummingbird (Calypte anna), for example, will hold a core territory of 
about 0.25 ac (0.1 ha) and a ``buffer zone'' of variable size, but 
usually 10-15 ac (4-6 ha) (Russell 1996, pp. 1-13). Hummingbirds are 
not restricted to these territories, but may venture greater distances 
crossing through neighboring territories to feed. Additionally, because 
extant populations of C. loncholepis are located within the Pacific 
flyway for migratory birds, while migrating, hummingbirds could forage 
in one population one day, and in another population later that day or 
the next day, thereafter, until either reaching their breeding or 
wintering grounds, or traveling beyond the range of C. loncholepis.
    Seed Dispersal Vectors: According to Craddock and Huenneke (1997, 
pp. 215-219), Cirsium seeds are usually wind-dispersed, but birds and 
small mammals also disperse Cirsium seeds (Burton and Black 1978, pp. 
383-390; Bent 1940, pp. 332-352, 1968, pp. 447-466). According to Keil 
and Turner (1993, pp. 232-239), wind is a likely dispersal vector for 
C. loncholepis seeds based on the architecture of their achenes, which 
are topped by an umbrella of long awns that are ideal for wind 
dispersal. The distribution of plants within a population (often an 
elongated pattern) is consistent with seed dispersal caused by the 
prevailing coastal winds (Lea 2002, pp. 1-84; Teed 2003, pp. 1-58). 
Additional dispersal vectors for C. loncholepis include small mammals 
and birds. Several small mammals that feed on seed of Cirsium species 
and move them among their seed caches live in the range of C. 
loncholepis. These include such species as kangaroo rats (Dipodomys 
spp.), pocket gophers (Thomomys bottae), California ground squirrels 
(Spermophilus beecheyi), and pocket mice (Perognathus spp.) (Blecha et 
al. 2007, pp. 1-354; Burton and Black 1978, pp. 383-390). Some small 
mammals, such as mice, use Cirsium tufts or down (the achene and 
pappus) as nest material (Root 2008, unpaginated). Various mammals such 
as mule deer (Odocoileus hemionus) and cattle occur in the Callender-
Guadalupe Dunes and have been documented grazing on thistle here 
(Nellis and Ross 1969, pp. 191-195; Theo et al. 2000, pp. 73-80; Blecha 
et al. 2007, pp. 1-354; Elvin 2007a, unpaginated). Some bird species, 
such as American Goldfinch (Carduelis tristis) and hummingbirds, some 
of which live within the range of C.

[[Page 45813]]

loncholepis, use its tufts (or down) for nest construction (Bent 1940, 
pp. 332-352, 1968, pp. 447-466; Weydemeyer 1923, pp. 117-118; Blecha et 
al. 2007, pp. 1-354).
    Water has been shown to be an important dispersal vector for seeds 
in another thistle, C. vinaceum, which also occurs in spring and 
streamside habitats (Craddock and Huenneke 1997, pp. 215-219). Cirsium 
seeds disperse via water ``considerable distances along streams'' 
(Craddock and Huenneke 1997, pp. 215-219). Cirsium loncholepis 
populations have been documented from the upper reaches of drainages 
and watersheds outlined below to suitable sites near the mouths of the 
rivers and creeks (within 1,000 ft (300 m)) of the Pacific Ocean (CNDDB 
2007, unpaginated; Santa Barbara Botanic Garden Herbarium 2007, 
unpaginated; University of California Santa Barbara Herbarium 2007, 
unpaginated).

Sites for Reproduction, Population Growth, and Dispersal

    Cirsium loncholepis has been reported from one or more polygons 
within 25 occurrences that are part of 11 populations distributed 
throughout 2 dune complexes and 4 drainages. All of these groupings are 
connected to each other in one or more ways. Cirsium loncholepis is 
closely associated with wetlands and mesic sites on the margins along 
four drainages that end in the Pacific Ocean (Arroyo Grande Creek, 
Santa Maria River, San Antonio Creek, and Santa Ynez River) (CNDDB 
2007, unpaginated; Consortium of California Herbaria 2008, 
unpaginated). Cirsium loncholepis has not been seen along Arroyo Grande 
Creek since 1910, so this area is not considered to be essential and 
will not be discussed further in this rule. The dynamic nature of these 
drainages is an essential part of the life cycle for C. loncholepis. 
The habitat along these creeks and rivers is constantly changing. It is 
under a constant state of succession and renewal. A mosaic of habitat 
occurs along these drainages with new suitable sites being created with 
every storm or flow event. The flows of water are also an important 
mechanism to move seeds from currently occupied sites to these newly 
created suitable sites.
    Orcutt Creek runs from the southeast to the northwest parallel with 
wind direction in the area. The headwaters for Orcutt Creek are 
southeast of the town of Orcutt on the northwest face of Graciosa 
Ridge. The stretch of Orcutt Creek near the town of Orcutt is one of 
the two likely sites where the type specimens were collected (see 
discussion in Background section). Orcutt Creek flows to the northwest 
and enters into the Santa Maria River near the Pacific Ocean. Cirsium 
loncholepis seeds that are deposited in the waters of Orcutt Creek 
would flow downstream from Orcutt toward the Santa Maria River. This 
stretch of the Santa Maria River has historically contained the largest 
population of C. loncholepis. Most of the records for C. loncholepis 
are from within the historical boundaries of the Santa Maria River 
floodplain.
    Graciosa Ridge is the dividing line between the headwaters of 
Orcutt Creek (in the Santa Maria River watershed) and Ca[ntilde]ada de 
las Flores (in the San Antonio Creek watershed). Because the prevailing 
winds in this area are from the northwest, Cirsium loncholepis seed in 
the Orcutt area would likely be blown over Graciosa Ridge toward 
Ca[ntilde]ada de las Flores, which is southeast of the headwaters of 
Orcutt Creek. Ca[ntilde]ada de las Flores, which flows south, is the 
headwaters for one of the tributaries of San Antonio Creek which flows 
to the Pacific Ocean. The estuary system (lagoon) at the mouth of San 
Antonio Creek was described by Fray Juan Crespi as La Graciosa in 1769 
(Smith 1976, p. 282, 1998, pp. 153-154) and is the other of the two 
most likely sites where the type specimen of C. loncholepis was 
collected (see discussion in Background section).
    The Santa Ynez River flows from east to west where it empties into 
the Pacific Ocean. The prevailing, strong winds in this area, from the 
west, would move Cirsium loncholepis seeds eastward, which is further 
upriver. Any resulting seed from upriver C. loncholepis populations 
that are deposited in the waters of the Santa Ynez River would then 
flow downstream toward the estuary system at the mouth of the river. 
Seed from any occurrence in the Santa Ynez River population would 
likely be dispersing to other occurrences in the Santa Ynez River 
(e.g., seed from upriver plants dispersing to the estuary plants via 
water and seed from estuary plants dispersing to the upriver plants via 
wind).

Habitats That Are Representative of the Historical, Geographical, and 
Ecological Distributions of Cirsium loncholepis

    Cirsium loncholepis has throughout time had a limited distribution 
in southwestern San Luis Obispo County and northwestern Santa Barbara 
County, California, within a unique geomorphic area known as the Santa 
Maria Basin (Hunt 1993, pp. 5-72). See Figure 2 for a map containing 
the locations of place and feature names in this region. The Santa 
Maria Basin stretches along a 39-mi (63-km) section of the coastal 
region of central California that is dominated by a system of dune 
complexes that are interspersed with several major drainages. The Santa 
Maria Basin is comprised of the Santa Maria Valley, in the north, and 
the Santa Ynez Valley, in the south. The Santa Maria Valley is located 
between the hills northeast of Pismo and the Casmalia and Solomon Hills 
that end at Point Sal in the west. The Santa Ynez Valley is located 
between the Casmalia and Solomon Hills and the Santa Ynez Mountains (on 
the south side of the Santa Ynez River). The Santa Maria Basin is 
dominated by moderate to strong winds from the northwest (categorized 
as greater than 7.47 miles per hour (mph) (12.02 kilometers per hour 
(kph))) most of the time and throughout the year (USDA NRCS 2008, 
unpaginated; National Oceanic and Atmospheric Administration Western 
Regional Climate Center (NOAA) 2007, unpaginated; Hendrickson 1990, pp. 
1-25). These prevailing northwest winds are a major factor in shaping 
the terrain and creating the dunes such that the active dune and swale 
systems are aligned with these winds (Hunt 1993, pp. 5-72). Deflation 
areas (the swales between two parallel dunes and behind the foredunes) 
are often at or near the water table, creating the wetlands and back-
dune lakes (Hunt 1993, pp. 5-72). This terrain, the parallel ridges and 
swales, and the physical features that created and maintain it are 
essential for the conservation of C. loncholepis.
BILLING CODE 4310-55-P

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[GRAPHIC] [TIFF OMITTED] TP06AU08.001


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Santa Maria Valley

    The Santa Maria Valley contains one major dune complex (the Santa 
Maria Valley Dune Complex) and three major riparian systems (or 
drainages): Arroyo Grande Creek, the Santa Maria River, and Orcutt 
Creek. The Santa Maria Valley Dune Complex contains five Dune Sheets 
(or associated sand depositional episodes): Callender, Nipomo Mesa, 
Guadalupe, Mussel Rock, and Orcutt Terrace. Individual dune sheets 
represent sequential and spatially overlapped depositional episodes 
within contiguous areas of any particular dune complex. Arroyo Grande 
Creek and its floodplain are at the northern edge of the Callender Dune 
Sheet (specifically) and the Santa Maria Valley Dune Complex (in 
general) (Hunt 1993, pp. 5-72). The junction of Arroyo Grande Creek and 
the Callender Dune Sheet also marks the northern limit for Cirsium 
loncholepis, which occurred here in the low ``grassy'' areas among the 
sand hills at the junction of the dunes and Arroyo Grande Creek 
(University of California [Berkeley] Herbarium 2007, unpaginated). The 
Callender Dune Sheet reaches Oso Flaco Creek and Oso Flaco Lake at its 
southern extent. Cirsium loncholepis has occurred at numerous sites 
throughout the Callender Dunes (Hendrickson 1990, pp. 1-25; CNDDB 2007, 
unpaginated). The Guadalupe Dune Sheet extends from Oso Flaco Lake to 
the Santa Maria River. Cirsium loncholepis has occurred at numerous 
sites throughout the Guadalupe Dunes (Hendrickson 1990, pp. 1-25; CNDDB 
2007, unpaginated). The Santa Maria Valley is a broad floodplain that 
is bounded by Orcutt Creek along its southern edge and by the Callender 
Dune Sheet and the Nipomo Dune Sheet (including Nipomo Mesa) along its 
northern edge. Between the city of Santa Maria and the coast 12 mi (19 
km) to the west, the valley floor has historically been dotted with 
small settlements and a few oil fields, but the vast majority of the 
land has been converted to agriculture. A member of the Gaspar de 
Portola expedition to Monterey in 1769 noted that the expedition had 
difficulty getting through the Santa Maria Valley because of all the 
marshes (Companys 1983, pp. 105-344). As has been typical along the 
central coast of California, however, many of the valley's wetlands 
have been drained or filled to maximize agricultural production; old 
maps show lakes such as Lake Guadalupe that no longer exist. Cirsium 
loncholepis has occurred at numerous mesic sites throughout the Santa 
Maria River floodplain and the Guadalupe Dunes (Hendrickson 1990, pp. 
1-25; CNDDB 2007, unpaginated). Orcutt Creek and the Santa Maria River 
mark the northern edge of the Mussel Rock Dune Sheet, which has had 
multiple C. loncholepis occurrences (Hendrickson 1990, pp. 1-25; CNDDB 
2007, unpaginated). Cirsium loncholepis most likely had a more 
widespread distribution within this area, but may have been eliminated 
from most of the locations in this area by the vast conversion of this 
area to agriculture before it could be documented. However, even with 
such conversion, current aerial photos and topographic maps show the 
persistence of numerous, small marshes, wetlands, and drainages in this 
area; some of these may still harbor small populations of C. 
loncholepis.

Santa Ynez Valley

    The Santa Ynez Valley contains one major dune complex (the Santa 
Ynez Valley Dune Complex) and two major riparian systems (or 
drainages): San Antonio Creek and the Santa Ynez River. The Santa Ynez 
Valley Dune Complex contains three Dune Sheets: San Antonio, Burton 
Mesa, and Lompoc Terrace. The San Antonio Terrace Dune Sheet is at the 
northern edge of the Santa Ynez Valley Dune Complex. It supports 
numerous dune wetlands and swales and is very similar in habitat, 
physical, and geological features to the Callender and Guadalupe Dune 
Sheets (Hunt 1993, pp. 5-72; Google Earth 2008, unpaginated). San 
Antonio Creek is downwind on the southern edge of the San Antonio 
Terrace Dune Sheet. The mouth of San Antonio Creek is one of the two 
most likely sites for the type locality (La Graciosa) for Cirsium 
loncholepis (Keil and Holland 1998, pp. 83-84; Oyler et al. 1995, pp. 
1-76; Hendrickson 1990, pp. 1-25; Smith 1976, p. 282, 1998, pp. 153-
154) and still harbors numerous small marshes and wetlands that are 
apparent in aerial imagery (Google Earth 2008, unpaginated). Historical 
collections indicate that C. loncholepis used to occur along the Santa 
Ynez River, somewhere between the towns of Surf and Lompoc, at the 
current edge of Vandenberg Air Force Base (University of Minnesota 
Saint Paul Herbarium 2007, unpaginated; Rancho Santa Ana Botanic Garden 
Herbarium 2007, unpaginated; Santa Barbara Botanical Garden Herbarium 
2007, unpaginated; University of California Riverside Herbarium 2007, 
unpaginated). Collections of the plant were made here in 1958; however, 
by 1988 when surveys were conducted to relocate this population, none 
could be found (Hendrickson 1990, pp. 1-25). Over the years, some, but 
not all, habitat for C. loncholepis in the floodplain for the river has 
been altered. According to Smith's notes, agricultural fields have been 
plowed to the banks of the drainage, willows have been bulldozed, and 
herbicides were sprayed to eradicate C. vulgare (bull thistle) (Smith 
1976, p. 282, 1998, pp. 153-154). Because this area historically 
supported the southernmost, documented C. loncholepis populations and 
because some habitat still remains today, it is considered to be an 
important area for the conservation of C. loncholepis (Morey 1990, pp. 
1-13; U.S. Fish and Wildlife Service 2008, unpaginated).
    Historically, Cirsium loncholepis has been reported or documented 
from a total of 25 occurrences as parts of 11 populations ranging from 
the dunes near Pismo Beach inland to hillside seeps at Ca[ntilde]ada de 
las Flores south to the floodplains of the Santa Ynez River (CNDDB 
2007, unpaginated; Consortium of California Herbaria 2008, 
unpaginated). At the time of the listing in 2000, there were 17 known 
occurrences of which 11 were extant. These 11 extant occurrences were 
distributed among 7 populations (65 FR 14888, March 20, 2000; CNDDB 
1998, unpaginated). Since the time of listing in 2000, C. loncholepis 
has experienced considerable declines throughout its range in the 
number of both occurrences and populations and in the number of 
individuals within each of the remaining occurrences and populations. 
Currently, C. loncholepis is considered to be extant at seven 
occurrences that are distributed among four populations. The seven 
extant occurrences consist of five occurrences that were identified in 
the final listing rule in 2000 as well as two new occurrences that have 
been identified since that time (CNDDB 2007, unpaginated; Elvin 2006, 
unpaginated, 2007a, unpaginated). Cirsium loncholepis does not 
currently occur at the following populations: Oceano, northern 
Callender Dune Sheet Lakes, Guadalupe, La Graciosa, Ca[ntilde]ada de 
las Flores, San Antonio Terrace Dune Sheet, and Santa Ynez River. Since 
the time of listing, the loss of known polygons, occurrences, and 
populations has outpaced the discovery of new polygons, occurrences, 
and populations.
    In habitats that are fragmented and/or isolated, the trend for 
native plant species is one of decline (Soule et al. 1992, pp. 39-47). 
This supports the equilibrium theory of island biogeography (MacArthur 
and Wilson, 1963, pp. 373-387, 1967) that predicts that species with 
populations that are isolated and have more extirpation events than re-
colonization events will

[[Page 45816]]

decline to zero (extinction). Recent research on species that are long-
distance dispersers (such as Cirsium loncholepis) determined that when 
the distances between suitable habitat sites for a species become 
greater than its dispersal distance (such as due to habitat 
fragmentation); its long-term survival will be threatened unless the 
long-distance dispersal between the sites can be re-established 
(Trakhtenbrot et al. 2005, pp. 173-181). The study by Trakhtenbrot et 
al. (2005, pp. 173-181) regarding long-distance dispersal species 
supports the study by Soule et al. (1992, pp. 39-47) and the 
equilibrium theory of island biogeography (MacArthur and Wilson 1963, 
pp. 373-387, 1967). Based on these studies and our current 
understanding of this species and its decline, we believe that 
conserving solely the areas with the remaining known occurrences and 
populations of C. loncholepis is not sufficient to conserve or recover 
the species. The additional habitat that would provide connectivity 
between occurrences and populations is essential for the conservation 
and recovery of C. loncholepis. This is supported by Damschen et al. 
(2006, pp. 1284-1286), who showed that habitat patches that were 
connected by corridors benefitted wildlife and plants.

Primary Constituent Elements for Cirsium loncholepis

    For areas within the geographical area occupied by Cirsium 
loncholepis at the time of listing, we must identify the PCEs that may 
require special management considerations or protection. Based on the 
above needs and our current knowledge of the life history, biology, and 
ecology of the species, we have determined the PCEs for C. loncholepis 
are:
    1. Mesic areas associated with: (a) Margins of dune swales, dune 
lakes, marshes, and estuaries that are associated with dynamic 
(changing) dune systems including the Santa Maria Valley Dune Complex 
and Santa Ynez Valley Dune Complex; (b) margins of dynamic riparian 
systems including the Santa Maria and Santa Ynez Rivers and Orcutt and 
San Antonio Creeks; and (c) freshwater seeps and intermittent streams 
found in other habitats, including grassland, meadow, coastal scrub, 
chaparral, and oak woodland. These areas provide space needed for 
individual and population growth including sites for germination, 
reproduction, seed dispersal, seed bank, and pollination.
    2. Associated plant communities including: Central dune scrub, 
coastal dune, coastal scrub, freshwater seep, coastal and valley 
freshwater marsh and fen, riparian scrub (e.g., mule fat scrub, willow 
scrub), chaparral, oak woodland, intermittent streams, and other 
wetland communities, generally in association with the following 
species: Juncus spp. (rush), Scirpus spp. (tule), Salix spp. (willow), 
Toxicodendron diversilobum (poison oak), Distichlis spicata (salt 
grass), Baccharis pilularis (coyote brush), and B. douglasii (Douglas' 
baccharis).
    3. Soils with a sandy component including but not limited to dune 
sands, Oceano sands, Camarillo sandy loams, riverwash, and sandy 
alluvial soils.
    4. Features that allow dispersal and connectivity between 
populations, particularly: (a) Natural riparian drainages in Santa 
Maria River, Orcutt Creek, San Antonio Creek, and Santa Ynez River that 
are not channelized or confined by barriers or dams, such that they 
have soft bottoms and sides and a natural flood plain (allowing 
uninterrupted water flows); and (b) natural aeolian geomorphology in 
the Santa Maria Dune Complex and Santa Ynez Dune Complex, and along the 
Santa Maria River, Orcutt Creek, San Antonio Creek, and Santa Ynez 
River drainages that is not confined by barriers or wind-blocks such as 
large man-made structures, tree rows, or wind-breaks (allowing 
uninterrupted winds across these areas).
    We believe that C. loncholepis could be conserved and recovered if 
populations in habitat with essential features remain connected 
throughout the two dune complexes and four major watersheds where it 
once was known to occur. With this proposed revision of critical 
habitat, we intend to identify the physical and biological features 
that are essential to the conservation of the species, through the 
identification of the appropriate quantity and spatial arrangement of 
the PCEs sufficient to support the life history functions of the 
species. Each of the areas proposed in this rule have been determined 
to contain at least one PCE to provide for the life history functions 
of C. loncholepis. Units are proposed for designation based on one or 
more PCEs being present to support one or more of the species' life 
history functions.

Special Management Considerations or Protections

    When designating critical habitat, we assess whether the occupied 
areas contain the physical or biological features essential to the 
conservation of the species, and whether these features may require 
special management considerations or protection. It is recognized that 
numerous activities in and adjacent to the unit designated as critical 
habitat, as described in this proposed rule, may affect one or more of 
the PCEs found in that unit. These activities include, but are not 
limited to, those listed in the Application of the ``Adverse 
Modification'' Standard section as activities that may destroy or 
adversely modify critical habitat. We summarize here the primary 
threats to the physical and biological features essential to the 
conservation of the species.
    Many of the known occurrences of Cirsium loncholepis are threatened 
by direct and indirect effects from energy-related operations (i.e., 
maintenance activities, hazardous waste cleanup); development that 
results in additional habitat modification (i.e., agricultural and 
urban development); facility accidents by oil companies or Vandenberg 
Air Force Base; groundwater extraction in the Guadalupe Dunes and 
vicinity; hydrolog