Endangered and Threatened Wildlife and Plants: 90-Day Finding on a Petition To Delist the Astragalus magdalenae, 71795-71799 [05-23407]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 70, Number 229 (Wednesday, November 30, 2005)]
[Proposed Rules]
[Pages 71795-71799]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-23407]


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DEPARTMENT OF THE INTERIOR

Fish and Wildlife Service

50 CFR Part 17


Endangered and Threatened Wildlife and Plants: 90-Day Finding on 
a Petition To Delist the Astragalus magdalenae var. peirsonii 
(Peirson's milk-vetch)

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Notice of 90-day petition finding and initiation of status 
review.

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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce our 
90-day finding on a petition to delist Astragalus magdalenae var. 
peirsonii (Peirson's milk-vetch) as a threatened species pursuant to 
the Endangered Species Act (Act) of 1973, as amended (16 U.S.C. 1531 et 
seq.). We find that the petition presents substantial scientific or 
commercial information indicating that delisting Astragalus magdalenae 
var. peirsonii may be warranted. Therefore, we are initiating a status 
review of Astragalus magdalenae var. peirsonii to determine if 
delisting the species is warranted. To ensure that the review is 
comprehensive, we are soliciting scientific and commercial information 
regarding this species.

DATES: The finding announced in this document was made on November 30, 
2005. To be considered in the 12-month finding for this petition, 
comments and information must be submitted to the Service by January 
30, 2006.

ADDRESSES: Submit new information, materials, comments, or questions 
concerning this species to Field Supervisor, Carlsbad Fish and Wildlife 
Office, U.S. Fish and Wildlife Service, 6010 Hidden Valley Road, 
Carlsbad, California 92011; by facsimile to 760/431-9618; or by 
electronic mail to ``FW1PMV@fws.gov''. Please submit electronic 
comments in ASCII file format and avoid the use of special characters 
or any form of encryption. Please also include ``Attn: 90-Day Finding 
on Peirson's Milk-Vetch Delisting Petition'' in your e-mail subject 
header and your name and return address in the body of your message. If 
you do not receive a confirmation from the system that we have received 
your Internet message, contact us directly by calling our Carlsbad Fish 
and Wildlife Office at phone number 760-431-9440. Please note that the 
e-mail address ``FW1PMV@fws.gov'' will be closed out at the termination 
of the public comment period. See also the ``Public Information 
Solicited''' section for more information on submitting comments. The 
complete file for this finding is available for public inspection, by 
appointment, during normal business hours at the above address.

FOR FURTHER INFORMATION CONTACT: Jim Bartel, Carlsbad Fish and Wildlife 
Office (see ADDRESSES), telephone 760-431-9440; facsimile 760-431-9618.

SUPPLEMENTARY INFORMATION:

Public Information Solicited

    When we make a finding that substantial information is presented to 
indicate that a delisting action may be warranted, we are required to 
promptly commence a review of the status of the species. Based on 
results of the status review, we will make a 12-month finding as 
required by section 4(b)(3)(B) of the Act. To ensure that the status 
review is complete and based on the best available scientific and 
commercial data, we are soliciting information on

[[Page 71796]]

the Peirson's milk-vetch. We request any additional data, references, 
comments, and suggestions from the public, other concerned governmental 
agencies, Native American Tribes, the scientific community, industry, 
or any other interested parties concerning the status of Peirson's 
milk-vetch. Of particular interest is information pertaining to the 
factors the Service uses to determine if a species is threatened or 
endangered: (1) Present or threatened destruction, modification, or 
curtailment of its habitat or range; (2) overutilization for 
commercial, recreational, scientific, or educational purposes; (3) 
disease or predation; (4) inadequacy of existing regulatory mechanisms; 
and (5) other natural or human-caused factors affecting its continued 
existence. In addition, we request data and information regarding the 
items identified in the ``Summary of Threats Analysis'' section.
    If you wish to comment, you may submit your comments and materials 
concerning this finding to the Field Supervisor, Carlsbad Fish and 
Wildlife Office (see ADDRESSES section). Our practice is to make 
comments, including names and home addresses of respondents, available 
for public review during regular business hours. Respondents may 
request that we withhold their home address, which we will honor to the 
extent allowable by law. There also may be circumstances in which we 
would withhold a respondent's identity, as allowable by law. If you 
wish us to withhold your name and/or address, you must state this 
request prominently at the beginning of your comment. We will not 
consider anonymous comments. To the extent consistent with applicable 
law, we will make all submissions from organizations or businesses, and 
from individuals identifying themselves as representatives or officials 
of organizations or businesses, available for public inspection in 
their entirety. Comments and materials received will be available for 
public inspection, by appointment, during normal business hours at the 
above address.

Background

    Section 4(b)(3)(A) of the Act requires that the Service make a 
finding on whether a petition to list, delist, or reclassify a species 
presents substantial scientific or commercial information indicating 
that the petitioned action may be warranted. This finding is based on 
information contained in the petition, supporting information submitted 
with the petition, and information otherwise available in our files at 
the time we make the finding. To the maximum extent practicable, we are 
to make this finding within 90 days of our receipt of the petition, and 
publish our notice of the finding promptly in the Federal Register.
    Our standard for substantial scientific or commercial information 
within the Code of Federal Regulations (CFR) with regard to a 90-day 
petition finding is ``that amount of information that would lead a 
reasonable person to believe that the measure proposed in the petition 
may be warranted'' (50 CFR 424.14(b)). If we find that substantial 
scientific or commercial information was presented, we are required to 
promptly commence a review of the status of the species.
    In making this finding, we relied on information provided by the 
petitioners and otherwise available in our files at the time of the 
petition review, and evaluated that information in accordance with 50 
CFR 424.14(b). Our process of coming to a 90-day finding under section 
4(b)(3)(A) of the Act and section 424.14(b) of our regulations is 
limited to a determination of whether the information in the petition 
meets the ``substantial scientific or commercial information'' 
threshold.
    Our 90-day finding considers whether the petitioners have stated a 
reasonable case that delisting may be warranted. Thus, our finding 
expresses no view as to the ultimate issue of whether the species 
should be delisted. We reach a conclusion on that issue only after a 
thorough review of the taxon's status. In that review, which will take 
approximately 9 more months, we will perform a rigorous, critical 
analysis of the best available commercial and scientific information. 
We will ensure that the data used to make our determination as to the 
status of the species (i.e., our 12-month finding) is consistent with 
the Act and the Information Quality Act (44 U.S.C. 3504(d)(1) and 
3516). Upon completion, our 12-month finding will be published promptly 
in the Federal Register.
    Astragalus magdalenae var. peirsonii (Peirson's milk-vetch) was 
listed as threatened on October 6, 1998 (63 FR 53596). At the time of 
listing, the primary threat to the milk-vetch was the destruction of 
individuals and dune habitat from off-highway vehicle (OHV) use and 
associated recreational development. On October 25, 2001, we received a 
petition to delist Astragalus magdalenae var. peirsonii dated October 
24, 2001, from David P. Hubbard, Ted J. Griswold, and Philip J. 
Giacinti, Jr. of Procopio, Cory, Hargreaves & Savitch, LLP, that was 
prepared for the American Sand Association (ASA), the San Diego Off-
Road Coalition, and the Off-Road Business Association (ASA 2001). On 
September 5, 2003, we announced an initial petition finding in the 
Federal Register that the petition presented substantial information to 
indicate the petitioned action may be warranted (68 FR 52784). In 
accordance with section 4(b)(3)(A) of the Act, we completed a status 
review of the best available scientific and commercial information on 
the species, and published our 12-month finding on June 4, 2004 (69 FR 
31523). We determined that the petitioned action was not warranted at 
that time. This determination met deadline requirements established by 
a court-approved settlement agreement (ASA et. al. v. USFWS and Gale 
Norton, Stipulated Settlement Agreement, Civ. No. 03-315L LAB).
    On July 8, 2005, we received a petition to delist Astragalus 
magdalenae var. peirsonii (Peirson's milk-vetch) that was prepared for 
the American Sand Association, the Off-Road Business Association, the 
San Diego Off-Road Coalition, the California Off-Road Vehicle 
Association, and the American Motorcycle Association District 37 (ASA 
2005). The new petition claims that according to four years of 
additional data collection, ``the Peirson's milk-vetch is even more 
abundant than was reported in ASA, et al.'s original petition, and that 
the plant's population and reproductive capacity are so stable and 
strong as to warrant delisting.''
    This petition and its associated documents also include claims and 
information previously addressed in our 90-day and 12-month findings on 
the previous petition to delist Peirson's milk-vetch. Those claims that 
are not substantially different from those addressed in our previous 
findings or that are not supported by additional information will not 
be addressed in this 90-day finding. However, all available 
information, including information provided by the petitioners in 
supplements to the petition dated September 8, 2005 and October 4, 
2005, will be considered in our status review and 12-month finding.

Species Information

Species Description

    Astragalus magdalenae var. peirsonii is an erect to spreading, 
herbaceous, short-lived perennial in the Fabaceae (Pea family) (Barneby 
1959, 1964). Plants may reach 8 to 27 inches (in) (20 to 70 centimeters 
(cm)) in height and develop taproots (Barneby 1964) that penetrate to 
the deeper, moister sand. According to Phillips and Kennedy (2003), 
plants largely die back to a root crown in the summer. The stems and 
leaves are covered with fine, silky

[[Page 71797]]

appressed hairs. The leaflets, which may fall off in response to 
drought, are small and widely spaced, giving the plants a brushy 
appearance. This taxon is unusual in that the terminal leaflet is 
continuous with the rachis rather than articulated with it. The purple 
flowers are arranged in 10- to 17-flowered axillary racemes.

Taxonomy

    The taxonomic status of Peirson's milk-vetch was discussed in the 
final listing rule (63 FR 53596). Although Peirson's milk-vetch was 
originally described at the species rank, it is currently recognized as 
a variety as Astragalus magdalenae var. peirsonii. There are two other 
currently recognized varieties of this species, but these are 
restricted to Mexico.
    Two other Astragalus taxa occur in the Algodones Dunes region. They 
are Astragalus lentiginosus var. borreganus, which is easily 
distinguished by its conspicuously broad leaflets, and Astragalus 
insularis var. harwoodii, which is easily distinguished by its smaller 
stature and shorter banner petals.

Range and Distribution

    Astragalus magdalenae var. peirsonii is reported from northeastern 
Baja California, Mexico (Barneby 1959, 1964; WESTEC 1977; Spellenberg 
1993), and has been verified in the Gran Desierto of Sonora, Mexico 
(Felger 2000). In the United States, this plant is restricted to about 
53,000 acres (ac) (21,500 hectares (ha)) in a narrow band of the 
central portion of the Algodones Dunes of eastern Imperial County, 
California, which are among the largest sand dune fields in North 
America. The Algodones Dunes are often referred to as the Imperial Sand 
Dunes. Nearly all of the lands in the Algodones Dunes are managed by 
the Bureau of Land Management (BLM) as the Imperial Sand Dunes 
Recreation Area (ISDRA). However, the State of California and private 
parties own small inholdings in the dune area. Approximately 21,836 ac 
(8,837 ha) of the 185,000-ac (74,867-ha) ISDRA have been designated as 
critical habitat for A. m. var. peirsonii (69 FR 47330).

Life History

    Astragalus magdalenae var. peirsonii has variously been considered 
an annual or perennial (Munz 1932, 1974; Barneby 1959, 1964; 
Spellenberg 1993; Willoughby 2001). Willoughby (2001) states that A. m. 
var. peirsonii is apparently a short-lived perennial, so its response 
to the amount of rainfall in the growing seasons is predictable. 
Documented persistence of individuals from one growing season to the 
next also attests to the perennial nature of A. m. var. peirsonii 
(Phillips and Kennedy 2002, 2003, 2004). Although Romspert and Burk 
(1979) found inflorescences present from December through at least 
April, plants are reportedly in flower from as early as mid-November 
through May (Barneby 1964; Porter in litt. 2003; Phillips and Kennedy 
2002). The plants are self-incompatible, requiring cross-pollination. 
The primary pollinator is a digger bee (Habropoda pallida) (Porter 
2005).
    Based on current understanding of the species' life history, 
sufficient rain in conjunction with cooler-than-average fall weather 
appears to trigger germination events. Seedlings may be present in 
suitable habitat throughout the dunes, especially during above-normal 
precipitation years. In drier years, plant numbers decrease as 
individuals die and are not replaced by new seedlings. The long-term 
survival of the species likely depends on the production of viable 
seeds in the wetter years, the continual replenishment of the seed 
bank, and the persistence of the seed bank. The seed bank allows the 
species to persist until appropriate conditions for germination, 
growth, and reproduction occur. Large annual fluctuations in the 
numbers of plants present have been consistently found (Phillips and 
Kennedy 2005; Willoughby 2004, 2005).
    The relative contribution of first year plants of Peirson's milk-
vetch to the seed bank and survival of the taxon is not fully 
understood. Available data (Phillips and Kennedy 2002, 2004, 2005) and 
previous research (Romspert and Burk 1979) suggest that older age 
classes produce substantially more seeds than first-year plants and 
that, therefore, the older persisting plants (i.e., those plants that 
survive for more than one growing season) may be individually important 
for depositing more seeds into the seed bank.
    In desert plants, the majority of seedlings may die at the onset of 
the drier season as noted by previous reports. Phillips and Kennedy 
(2002) reported that 26 percent of the plants recorded in Spring 2001 
counts survived to late 2001. These authors (Phillips and Kennedy 2003) 
also report the nearly complete loss of the 2003 seedling cohort of 
Peirson's milk-vetch. Pavlik and Barbour (1988) studied the 
establishment and survivorship pattern of Astragalus lentiginosus var. 
micans, another dune endemic plant, and recorded a complete failure of 
the 1984-1985 seedling cohort. These authors also reported that 54 
percent of the 1985-1986 cohort of seedlings survived. However, none of 
these plants reached reproductive maturity that year.

Seed Biology

    The fruits of Peirson's milk-vetch are 0.8 to 1.4 in (2 to 3.5 cm) 
long, one-chambered, hollow, and inflated. Peirson's milk-vetch fruits 
contain 11 to 16 large flattened black seeds. The seeds, among the 
largest seeds of any Astragalus in North America (Barneby 1964), 
average less than 0.1 ounces (oz) (15 milligrams (mg)) each in weight 
and are up to 0.2 in (4.7 millimeters (mm)) in length (Bowers 1996). 
Seeds are either dispersed locally when they fall from partly opened 
fruits on the parent plant, or more widely when they are released from 
fruits blown across the sand after falling from the parent plant. Seeds 
require no pre-germination treatment to induce germination, but show 
increased germination success when scarified (outer cover is broken). 
Porter (2005) reported about 9.1 percent of scarified seeds germinated 
while only 5.3 percent of unscarified seeds germinated. In germination 
trials conducted by Romspert and Burk (1979), 92 percent or more seeds 
germinated within 29 days at temperatures of 77 [deg]F (25 [deg]C) or 
less, and no seeds germinated at temperatures of 86 [deg]F (30 [deg]C) 
or higher. This indicates that seeds on the dunes may likely germinate 
in the cooler months of the year. Porter (in litt. 2002) identified 
that the primary dormancy mechanism in Peirson's milk-vetch is the 
impermeability of the seed coat to water and demonstrated little loss 
of viability in seeds stored for three years. This mechanism is 
consistent with characteristics of other species that have seed banks 
(Given 1994). Dispersed seeds that do not germinate during the 
subsequent growing season become part of the seed bank (Given 1994).
    In a given year, an annual or short-lived species can fluctuate 
between large numbers of plants to few or even no plants. Many species, 
and Peirson's milk-vetch may be one of them, have periodic ``rescue'' 
episodes from the seed bank where large flushes appear when germination 
conditions are suitable (Elzinga et al. 1998). To the extent that 
plants are precluded from adding seeds to the seed bank because the 
plants are eliminated entirely or their reproductive output is reduced 
by summer drought, herbivory, and OHV impacts, these individuals cannot 
be expected to contribute to the seed bank and/or long-term survival of 
Peirson's milk-vetch. Development of a seed bank and associated 
dormancy allows plant species to grow, flower, and set seed in

[[Page 71798]]

years with most favorable conditions (Given 1994). When measuring seed 
bank dynamics to determine the viability and productivity of a seed 
bank, among the factors necessary to consider are estimation of the 
rate of seed mortality and aging, the amount of seed removed by 
predators, and the variability in germination events (Elzinga et al. 
1998).

Threats Analysis

    When considering an action for listing, delisting, or reclassifying 
a species, we are required to determine whether a species is endangered 
or threatened based on one or more of the five listing factors as 
described at 50 CFR 424.11. These factors are given as: (A) The present 
or threatened destruction, modification, or curtailment of its habitat 
or range; (B) overutilization for commercial, recreational, scientific, 
or educational purposes; (C) disease or predation; (D) the inadequacy 
of existing regulatory mechanisms; and (E) other natural or manmade 
factors affecting the continued existence of the species. Delisting a 
species must be supported by the best scientific and commercial data 
available and only considered if such data substantiates that the 
species is neither endangered nor threatened for one or more of the 
following reasons: (1) The species is considered extinct; (2) the 
species is considered to be recovered; and/or (3) the original data 
available when the species was listed, or the interpretation of such 
data, were in error. In making this finding, we evaluated whether or 
not the petition and associated documents and other information 
available to us present substantial information that delisting 
Peirson's milk-vetch may be warranted. Our evaluation, based on 
information provided in the petition and available in our files, is 
presented below.
    The petitioners provided us with four reports completed since our 
2004 12-month finding (69 FR 31523). These new reports include the work 
by BLM (Willoughby 2004, 2005) and reports by Phillips and Kennedy 
(2004, 2005).

A. Present or Threatened Destruction, Modification, or Curtailment of 
the Species' Habitat or Range

Demography of Peirson's Milk-Vetch
    The petition restates claims made in the October 2001 petition that 
(1) the original listing was made without a plant count and (2) the 
original listing relied on field studies that BLM has since indicated 
were biased. As noted above in the Background section, we will not be 
addressing in this 90-day finding those claims that are not 
substantially different from those addressed in our previous findings 
or are not supported by additional information.
    The petition states that its point is ``to demonstrate, through 
four years of additional data collection, that the Peirson's milk-vetch 
is even more abundant than was reported in ASA et al.'s original 
petition, and that the plant's population and reproductive capacity are 
so stable and strong as to warrant delisting'' (ASA 2005 p. 5). The 
petitioners suggest that (1) the addition of several years of 
monitoring data by BLM (Willoughby 2004, 2005) and Phillips and Kennedy 
(2004, 2005) indicate that Peirson's milk-vetch has a ``large and 
stable population'' (ASA 2005 p. 46) and (2) new data gathered by 
Phillips and Kennedy (2004, 2005) on Peirson's milk-vetch reproductive 
strategy indicate that the plant has the capacity to produce large 
numbers of seeds to restock the seed bank.
    Using, in particular, the results of the monitoring by BLM 
(Willoughby 2004, 2005) and Phillips and Kennedy (2004, 2005), the 
petitioners state that the ``anticipated threats to the Peirson's milk-
vetch and its habitat have not materialized'' (ASA 2005 p. 47). 
Instead, they state that threats to its ``continuous existence are 
negligible'' (ASA 2005 p. 48).
Off Highway Vehicle (OHV) Use
    A primary threat that led to the listing of the Peirson's milk-
vetch in 1998 was the destruction of individuals and habitat from OHV 
use and associated recreational development (63 FR 53596). The current 
petition (ASA 2005) and associated new documents provide information 
that bears on the impact of OHV activity on Peirson's milk-vetch. 
Monitoring studies conducted by BLM (Willoughby 2004, 2005) provide 
updated information on Peirson's milk-vetch abundance classes, use of a 
new monitoring protocol, estimates of density and population, and OHV 
impacts. Studies conducted by Phillips and Kennedy (2004, 2005) provide 
information on germination events and their timing, survivorship, seed 
bank, estimates of density and population size, OHV impacts, and 
additional surveys for Peirson's milk-vetch.
Evaluation of Information in the Petition and Other Information in Our 
Files
    Willoughby (2004) summarizes multiple years of monitoring of 
Peirson's milk-vetch and Helianthus niveus ssp. tephrodes (Algodones 
Dunes Sunflower) in the Algodones Dunes. For each transect used in 
previous BLM surveys, Willoughby (2004) included number of plants 
tallied, sums of abundance class values, and number of cells occupied. 
Willoughby (2004) reports that there is essentially no difference in 
the number of cells per transect occupied by Peirson's milk-vetch in 
areas opened or closed to OHV use. Willoughby (2004) noted that part of 
the area surveyed and considered as ``open area'' was, in fact, closed 
to OHV use during 2001 and 2002. The report concludes that the 
populations of Peirson's milk-vetch fluctuate with rainfall but there 
was no difference between open and closed areas. Willoughby (2005) 
estimated that there were 286,374 Peirson's milk-vetch plants with 
plant density estimated to be 13.5 plants per ha (33.3 ac). Willoughby 
(2005) included estimates of numbers of the total plants that were 
flowering adults in 2004 and seedling survival for seedlings found in 
spring 2004 until September 2004.
    Phillips and Kennedy (2004, 2005) provide information on 
survivorship, germination, seed bank, and population estimates of 
Peirson's milk-vetch based on counts at their study sites. They report 
actual plant counts of 77,922 individuals in March 2005 and 66,931 
individuals in April 2005 at 25 sample sites. Within 56 ha (138 ac) of 
potential habitat, Phillips and Kennedy (2005) estimate an approximate 
minimum population of 173,328 plants in March 2005 and 142,243 plants 
in April 2005. They describe finding approximately 30 seedlings in 
Anza-Borrego Desert State Park (an area outside of Algodones Dunes).
    To summarize, the petitioners have presented new information on the 
demography of Peirson's milk-vetch. Some of this information may be 
relevant to the potential impacts of OHV activities on the plant and 
its habitat. They support their arguments that Peirson's milk-vetch is 
healthy and stable and that OHV impacts are minimal with information 
from four reports (Willoughby 2004, 2005 and Phillips and Kennedy 2004, 
2005) that were not available at the time of the previous 12-month 
finding (69 FR 31523). We find that these documents present substantial 
information that the petitioned action may be warranted and that they 
justify further detailed analysis in a 12-month finding. Additional 
information in our files includes a study on the biology of Peirson's 
milk-vetch (Porter 2005) and a Service study on plant densities in the 
Algodones Dunes (Service 2005b). All of these materials will be 
included in the species status review as part of the 12-month finding.

[[Page 71799]]

B. Overutilization for Commercial, Recreational, Scientific, or 
Educational Purposes

    This petition (ASA 2005) does not present any information regarding 
this factor as a threat to Peirson's milk-vetch nor did we identify any 
threats relative to Factor B in our previous 12-month finding (69 FR 
31523). If new information becomes available in public comments, we 
will analyze it in our 12-month finding.

C. Disease or Predation

    The petition (ASA 2005) states that Peirson's milk-vetch is largely 
free of threats from disease or predation. This is the same statement 
made in the original (ASA 2001) petition. We addressed the impact of 
seed-eating beetles (Bruchidae) on the seeds and evidence of rodent and 
insect herbivory in our previous 12-month finding (69 FR 31523). In 
2004, BLM recorded numbers and distribution of plants with damage. 
Damage that was not from OHV impacts was attributed principally to 
insects (Willoughby 2005).
    We identified potential additive Factor C threats in our previous 
12-month finding (69 FR 31523), but the current petition does not 
identify threats in this category. Therefore, the petition does not 
present substantial information related to Factor C. However, our new 
12-month finding will consider Factor C threats.

D. Inadequacy of Existing Regulatory Mechanisms

    This petition (ASA 2005) and the previous petition (ASA 2001) both 
state that Peirson's milk-vetch has received adequate protection from 
BLM since 1977. The claim in the current petition that BLM has 
adequately protected Peirson's milk-vetch does not appear to constitute 
substantial information in and of itself because the petitioners' 
discussion of the issue was brief. However, the issue may be clarified 
by further analysis in a 12-month finding, which would also consider 
the Service's biological opinion, signed January 25, 2005, for the 
Imperial Sand Dunes Recreational Area Management Plan (Plan) (Service 
2005a). We will analyze the Plan and the biological opinion as part of 
the 12-month finding.

E. Other Natural or Manmade Factors Affecting the Species' Continued 
Existence

    This petition (ASA 2005) and the earlier petition (ASA 2001) both 
state that there are no other natural or manmade threats to Peirson's 
milk-vetch. We discussed threats from purposeful impacts to Peirson's 
milk-vetch by OHVs, rangewide natural threats during years when the 
numbers of individuals is very low, and the role of pollinators in our 
previous 12-month finding (69 FR 31523).
    We identified Factor E threats in our previous 12-month finding (69 
FR 31523), but the current petition does not identify threats in this 
category. Therefore, the petition does not present substantial 
information related to Factor E. However, the information presented by 
the petition may affect our analysis of the existence and relative 
magnitude of the identified Factor E threats and our new 12-month 
finding will consider these threats in light of the new information.

Summary of Threats Analysis

    The petitioners have presented new information regarding the 
ecology and demography of Peirson's milk-vetch at the Algodones Dunes. 
Phillips and Kennedy (2004) include new information on seedling growth, 
documentation of a late winter germination in 2004, and a count of 
seedlings in 2004. Phillips and Kennedy (2005) provide new information 
on plant densities in three study areas, population estimates for those 
areas, results of a new survey area, and indicate that Peirson's milk-
vetch ``colonies'' are increasing in three different areas open to OHV 
use. Willoughby (2004, 2005) includes new information regarding 
population trends of Peirson's milk-vetch plants in the Algodones 
Dunes, abundance class differences for 2002, number of occupied cells 
per transect, seedling survival, OHV impacts, and the use of a new 
monitoring protocol for special status plants, including Peirson's 
milk-vetch, in the Algodones Dunes. These reports constitute 
substantial information that the petitioned action may be warranted and 
thus justify further detailed analysis in a status review and 12-month 
finding.

Finding

    We have reviewed the petition and associated documents and other 
information available in our files. Based on this review, and the 
reasons discussed above, we find that the petition and information in 
our files present substantial information that delisting of Peirson's 
milk-vetch may be warranted.

References Cited

    A complete list of all references cited herein is available, upon 
request, from the Carlsbad Fish and Wildlife Office (see ADDRESSES 
section).

Author

    The primary author of this notice is the Carlsbad Fish and Wildlife 
Office.

    Authority: The authority for this action is the Endangered 
Species Act of 1973, as amended (16 U.S.C. 1531 et seq.).

    Dated: November 17, 2005.
Richard E. Sayers, Jr.,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 05-23407 Filed 11-29-05; 8:45 am]
BILLING CODE 4310-55-P