[Federal Register: April 19, 1999 (Volume 64, Number 74)]
[Proposed Rules]               
[Page 19108-19111]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]



Fish and Wildlife Service

50 CFR Part 17

Endangered and Threatened Wildlife and Plants: 90-Day Finding for 
a Petition to List the Ambrosia pumila (San Diego Ambrosia) as 

AGENCY: Fish and Wildlife Service, Interior.

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


SUMMARY: We have made a 90-day finding on a petition to list the 
Ambrosia pumila (San Diego ambrosia) pursuant to the Endangered Species 
Act of 1973, as amended (Act). We find that the petition presents 
substantial scientific or commercial information indicating that 
listing Ambrosia pumila as endangered may be warranted. We are 
initiating a status review to determine if listing is warranted.

DATES: The finding announced in this document was made on April 13, 
1999. To be considered in the 12-month finding, comments and 
information must be submitted to us by May 19, 1999.

ADDRESSES: Submit data, information, comments, or questions concerning 
the petition and this 90-day finding to the Field Supervisor, U.S. Fish 
and Wildlife Service, Carlsbad Fish and Wildlife Office, 2730 Loker 
Avenue West, Carlsbad, California 92008. You may inspect the petition, 
90-day finding, supporting data, comments and related documents, by 
appointment, during normal business hours at the above address.

FOR FURTHER INFORMATION CONTACT: Douglas Krofta, biologist, U.S. Fish 

[[Page 19109]]

Wildlife Service at the above address or telephone 760-431-9440.



    Section 4(b)(3)(A) of the Endangered Species Act of 1973, as 
amended (16 U.S.C. 1531 et seq.) (Act), requires that we make a finding 
on whether a petition to list, delist, or reclassify a species presents 
substantial scientific or commercial information to demonstrate that 
the petitioned action may be warranted. To the maximum extent 
practicable, we are to make this finding within 90 days of receipt of 
the petition, and we are to publish the finding promptly in the Federal 
Register. If the finding is that substantial information was presented, 
we must promptly commence a review of the status of the species.
    We have made a 90-day finding on a petition to list Ambrosia pumila 
(San Diego ambrosia). Mr. David Hogan, of the Southwest Center for 
Biological Diversity, and Ms. Cindy Burrascano, of the San Diego 
Chapter of the California Native Plant Society, submitted the petition, 
dated November 12, 1996, which we received on January 9, 1997. The 
petition requested the listing of A. pumila as endangered pursuant to 
section 4 of the Act. Additionally, the petitioners appealed for the 
emergency listing of A. pumila pursuant to section 4(b)(7) of the Act, 
and further requested the designation of critical habitat for this 
plant taxon. The letter clearly identified itself as a petition and 
contained the names, signatures, and addresses of the petitioners. 
Accompanying the petition was supporting information relating to 
taxonomy, ecology, threats, and distribution of A. pumila. On November 
21, 1997, we received a 60-day notice of intent to sue from the 
petitioners over the failure to issue the administrative 90-day finding 
for A. pumila. The petitioners filed a lawsuit in the United States 
District Court on October 1, 1998, citing that we had failed to produce 
the administrative 90-day and 12-month findings for A. pumila.
    We have reviewed the petition, supporting documentation, and other 
information available in our files to determine if substantial 
information is available to indicate that the requested action may be 
warranted. On the basis of the best scientific and commercial 
information available, we find that the petitioned action may be 
warranted for Ambrosia pumila because of the magnitude of ongoing and 
threatened impacts to existing populations. We will commence a status 
review in accordance with the final listing priority guidance for 
fiscal years 1998 and 1999 (63 FR 25502) published on May 8, 1998.
    At the time the petition was received on January 9, 1997, we were 
operating under our final listing priority guidance for fiscal year 
1997, which was published December 5, 1996 (61 FR 64475) in the Federal 
Register. The guidance clarified the order in which we would continue 
to process the backlog of rulemakings following two related events--(1) 
the lifting, on April 26, 1996, of the moratorium on final listings 
imposed on April 10, 1995 (Pub. L. 104-6); and (2) the restoration of 
significant funding for listing through passage of the omnibus budget 
reconciliation law on April 26, 1996, following severe funding 
constraints imposed by a number of continuing resolutions between 
November 1995 and April 1996. Based on biological considerations, the 
guidance established a ``multi-tiered approach that assigned relative 
priorities, on a descending basis, to actions to be carried out under 
section 4 of the Act'' (61 FR 64479). The guidance called for giving 
highest priority (Tier 1) to handling emergency situations, second 
highest priority (Tier 2) to resolving the listing status of the 
outstanding proposed listings, third priority (Tier 3) to resolving the 
conservation status of candidate species and processing administrative 
findings on petitions, and lowest priority (Tier 4) to preparation of 
proposed or final critical habitat designations, and processing 
delistings and reclassifications from endangered to threatened status.
    On January 23, 1997, we notified the petitioners that based on the 
listing priority guidance for fiscal year 1997, we would conduct a 
preliminary review of the petition to determine whether Ambrosia pumila 
faced a significant risk to its well-being under the emergency listing 
provisions of section 4(b)(7) of the Act (61 FR 64479). We indicated 
that if such an emergency existed and the species fell within Tier 1, 
we would immediately process an emergency listing and proposed rule; if 
an emergency did not exist, the petitioned action would fall within 
Tier 3 of the guidance. On July 15, 1997, we made a determination that 
an emergency did not exist (i.e., the immediacy of threats to A. pumila 
were not so great to a significant proportion of the population that 
the routine listing process was insufficient to prevent large losses 
that might result in extinction). Therefore, the processing of the 
petition fell under Tier 3. Our Carlsbad Office (which was assigned the 
responsibility for processing the petition) continued to direct 
personnel and budget toward accomplishment of ongoing Tier 2 and Tier 3 
activities for species judged to be in greater need of the Act's 
protection than A. pumila. As these higher priority activities were 
accomplished, and personnel and funds became available, we proceeded 
with a 90-day finding on the petition for A. pumila.
    On May 8, 1998, final listing priority guidance for fiscal years 
1998 and 1999 (63 FR 25502) was published. This new guidance changed 
the four tier priority system to a three tier system. The three tier 
system described our first priority (Tier 1) as completion of emergency 
listings for species facing the greatest risk to their well-being. Our 
second priority (Tier 2) was processing final decisions on pending 
proposed listings; processing new proposals to add species to the 
lists; processing 90-day and 12-month administrative findings on 
petitions to add species to the lists and petitions to delist or 
reclassify species; and delisting or downlisting actions on species 
that have achieved or are moving towards recovery. Our third priority 
(Tier 3) described in the guidance was processing petitions for 
critical habitat designations and preparing proposed and final critical 
habitat designations. Under this current guidance, the processing of 
this petition fell under Tier 2.
    Ambrosia pumila is a clonal perennial herb restricted to upper 
terraces of rivers and drainages, but has been identified growing in 
open, flat grasslands; dry lake beds; open patches in coastal sage 
scrub habitat; and disturbed sites such as fuel breaks and roadway 
rights-of-way. Populations of San Diego ambrosia occur on federal, 
state, and private lands located in southwestern Riverside and San 
Diego counties, California, and Baja California, Mexico. The range of 
A. pumila is known from an estimated 53 documented historical and 
current populations from Riverside and San Diego counties, California, 
and central Baja California, Mexico from Colonet south to Lake Chapala. 
The distribution of A. pumila is centralized in San Diego County, where 
approximately 48 distinct populations have been reported. Recently, two 
populations of A. pumila were discovered in southwestern Riverside 
County. Although limited information is available concerning current 
populations of A. pumila in Baja California, three disjunct populations 
are presumed extant.

San Diego County

    Of the 48 reported populations of Ambrosia pumila in San Diego 
County, 23 have been extirpated, and an

[[Page 19110]]

additional 11 populations were misidentified and are actually a similar 
species A. confertiflora. This leaves 14 populations extant in San 
Diego County. Two populations consist of plants that were transplanted 
from sites where the taxon was extirpated due to roadway construction 
or development. Although these populations are extant, their long-term 
viability is in question due to unsuccessful attempts at transplanting 
the taxon in the past. Eleven of the remaining 12 populations have been 
recently field verified and are known to be extant. Insufficient 
information exists to make a determination on the status and viability 
of the twelfth population due to the inadequacy of data on the original 
collection and difficulty in site access. The long-term viability of at 
least 5 of the remaining 11 populations is in question due to 
population size, fragmentation, past and potential impacts, extent of 
suitable habitat in the immediate area, current land use practices and 
land-ownership. These apparently nonviable populations range in extent 
from a single plant growing up through a crack in a sidewalk in 
National City to a population consisting of several hundred or more 
stems at Gillespie Field. The six remaining populations in San Diego 
County are considered to have a greater degree of long-term persistence 
or viability primarily due to larger population sizes and current land 
use practices or ownership. These six populations include one 
population in Mission Trails Regional Park, two populations on the San 
Diego National Wildlife Refuge, one population on a dirt road off of 
Del Dios Highway, one population within a San Diego Gas and Electric 
(SDGE) gas line easement along State Route (SR) 76, and one population 
within a SDGE electrical transmission line easement adjacent to Jamul 
    The Mission Trails population is considered to be the largest and 
most viable population of Ambrosia pumila in the United States. It is 
located in Mission Trails Regional Park and on adjacent private 
property. Although road construction and adjacent urban development 
have historically fragmented the population, the core population 
consists of several thousand stems and several small colonies scattered 
throughout the general area. The petitioners asserted that the 
persistence of this core population is apparently essential to the 
survival of this taxon in the United States (Hogan and Burrascano 
1996). A minimum 90 percent of the core population in Mission Trails 
Regional Park is protected under the provisions of the Multiple Species 
Conservation Plan (MSCP) for southwestern San Diego County. Other 
populations within MSCP boundaries, such as the Del Dios Highway 
population, will receive protection under specific sub-area/sub-
regional plans addressing conservation measures on an individual 
project/population basis. The two populations located within the San 
Diego National Wildlife Refuge are conserved and managed as part of the 
National Wildlife Refuge System, and are not likely to be threatened. 
The two San Diego populations found within SDGE easements have the 
potential for long-term persistence but are currently outside the San 
Diego County MSCP boundaries. These two populations are protected by a 
habitat conservation plan with SDGE. Under this plan, the species is 
covered by special mitigation measures that involve avoidance of 
impacts as a first priority, and mitigation of impacts as a second 

Riverside County

    The two populations of Ambrosia pumila recently recorded in 
southwestern Riverside County are in the vicinity of Skunk Hollow and 
Lake Elsinore. The Skunk Hollow population consists of approximately 
500 stems and is located on private lands within a wetland mitigation 
bank. The Lake Elsinore population has an estimated 250-500 stems and 
is also located on private lands. The long-term persistence or 
viability of the Lake Elsinore population is in question due to current 
development threats.


    The current documented range of Ambrosia pumila in Baja California, 
Mexico extends from Colonet south to Lake Chapala. Three disjunct 
populations are recorded. Although additional sites may occur in Baja, 
the taxon is not considered to be widespread due to the lack of 
appropriate habitat and impacts resulting from agriculture and urban 
development, especially in coastal areas. Recent field reconnaissance 
(Hogan and Burrascano 1996) of two of the three documented sites has 
confirmed that the recorded populations are extant, but estimates on 
population size and long-term viability are inconsistent. All three of 
the known and presumed extant Baja California populations are 
threatened by agricultural practices and urban development. Further 
evaluation of these populations is necessary to determine their status 
and the immediacy of threats.


    All populations of Ambrosia pumila appear vulnerable to random, 
environmental or demographic events. Fire, natural or human-induced, 
could destroy one or more populations. Competition from other plant 
taxa is also a serious threat. While Ambrosia pumila is considered 
tenacious in appropriate habitat, it is thought to be a weak competitor 
with invasive herbaceous and non-native grass species.
    Of the 16 populations of Ambrosia pumila presumed extant in the 
United States, only six populations in San Diego County and one 
population in Riverside County are considered secure and protected. 
These seven populations are expected to persist, provided that adequate 
protection and management measures are established, implemented, and 
maintained. The permanent protection and management of A. pumila 
populations under multiple species conservation plans will contribute 
to long-term habitat viability for A. pumila.
    We have reviewed the petition, as well as other available 
information in our files. On the basis of the best scientific and 
commercial information available, we find that there is sufficient 
information to indicate that the petitioned action, listing Ambrosia 
pumila as endangered, may be warranted. The petitioners also requested 
that critical habitat be designated for this species. Designation of 
critical habitat is not petitionable under the Act. However, if we 
determine in the 12-month finding that the petitioned action is 
warranted, we will address the designation of critical habitat in the 
subsequent proposed rule.

Additional Information Solicited

    When we make a finding that substantial information exists to 
indicate that listing a species may be warranted, we are also required 
to promptly commence a review of the status of the species. To ensure 
that the status review is complete and based on the best available 
scientific and commercial data, we are soliciting information 
concerning the following:

(1) information on historic and current distribution;
(2) habitat conditions;
(3) basic biology of the species;
(4) ongoing efforts to protect the species and its habitat; and
(5) threats to the species and its habitat.

References Cited

    You may request a complete list of all references cited in this 
document from

[[Page 19111]]

the Carlsbad Fish and Wildlife Office (see ADDRESSES section).
    Author. The primary author of this document is Douglas Krofta, 
biologist, Carlsbad Fish and Wildlife Office, U.S. Fish and Wildlife 
Service (see ADDRESSES section).


    The authority for this action is the Endangered Species Act (16 
U.S.C. 1531 et seq.).

    Dated: April 13, 1999.
Jamie Rappaport Clark,
Director, Fish and Wildlife Service.
[FR Doc. 99-9783 Filed 4-15-99; 8:45 am]