[Federal Register Volume 62, Number 118 (Thursday, June 19, 1997)]
[Proposed Rules]
[Pages 33388-33390]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-15926]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
RIN: 1018-AC98
Endangered and Threatened Wildlife and Plants; Withdrawal of
Proposed Rule to List Arctostaphylos Imbricata (San Bruno Mountain
Manzanita) as Threatened
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Proposed rule; withdrawal.
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SUMMARY: The U. S. Fish and Wildlife Service (Service) withdraws the
proposal to list Arctostaphylos imbricata (San Bruno Mountain
manzanita) as a threatened species under the Endangered Species Act of
1973, as amended (Act). This determination is based on evaluation of
comments and additional information received subsequent to publication
of the proposed rule. Provisions of the San Bruno Mountain Habitat
Conservation Plan (HCP) pertaining to management for the conservation
of A. imbricata have been clarified. Other threats identified in the
proposed rule pertaining to fire frequency and overutilization for
horticultural purposes are no longer considered to pose a significant
risk to the survival of the species. Thus, protection under the Act is
unnecessary at this time.
ADDRESSES: The complete file for this rule is available for public
inspection, by appointment, during normal business hours at the
Sacramento Field Office, U.S. Fish and Wildlife Service, 3310 El Camino
Ave., Sacramento, California 95821-6340.
FOR FURTHER INFORMATION CONTACT: Diane Windham, at the above address or
by telephone at (916) 979-2725.
SUPPLEMENTARY INFORMATION:
Background
Alice Eastwood (1931) originally described Arctostaphylos imbricata
in 1931, based on material collected from the San Bruno Hills in 1915.
Until 1967, various authors either synonymized A. imbricata with A.
andersonii (Jepson 1939), or considered it to be a variety of A.
andersonii (Adams in McMinn 1935). Roof (1967) followed Eastwood's
treatment and acknowledged A. imbricata as a distinct species. Wells
(1988) recognized A. montariensis as a subspecies of A. imbricata
which, under the rules of botanical nomenclature, automatically created
the name (autonym) A. imbricata ssp. imbricata. He has since revised
his treatment of California Arctostaphylos to recognize A. imbricata as
a distinct species (Wells 1993).
Arctostaphylos imbricata is a low, spreading, evergreen shrub of
the heath family (Ericaceae) that lacks a basal burl. Attaining a
height of 20 centimeters (8 inches), this highly branched shrub forms
mats up to about 6 meters (m) (6 yards) in diameter. The bright green,
oblong to ovate leaves are hairless, except on the midrib, and densely
overlapping. Small, white, urn-shaped flowers appearing from February
to May are densely clustered at the end of branchlets. After fire, A.
imbricata regenerates from seed instead of resprouting from a basal
burl. Arctostaphylos imbricata can be distinguished from other members
of the genus by its prostrate form, its shorter, densely arranged
leaves, and its compact flower clusters (Roof 1967).
Arctostaphylos imbricata is restricted to San Bruno Mountain in
northern San Mateo County. On San Bruno Mountain, six small colonies
comprise one population which covers approximately 2.3 hectares (5.6
acres) (V. Harris, Thomas Reid Associates, in litt. 1993; R. Gankin,
San Mateo County Planning Department, in litt. 1994). The most abundant
colony has 400 to 500 plants; other colonies have as few as 3 plants
(R. Gankin, pers. comm. 1993; R. Gankin, in litt. 1994). The plant
grows on rocky, exposed areas such as open ridges within coastal scrub
or manzanita scrub vegetation at an elevation range of 275 to 365 m
(900 to 1,200 feet). Where it occurs, it is the dominant plant species,
and may be associated with Baccharis pilularis (coyote brush),
Vaccinium ovatum (huckleberry), Rhamnus californica (coffeeberry), and
Arctostaphylos uva-ursi var. suborbiculata (bearberry) (California
Department of Fish and Game 1988). Arctostaphylos imbricata has never
been known from more than the single population of six colonies that
occurs today. Five of the six colonies occur on land owned by the San
Mateo County Department of Parks and Recreation; the sixth colony is
privately owned (Thomas Reid Associates 1991). All colonies are located
within the San Bruno Mountain HCP boundaries.
Finding and Withdrawal
The proposed rule to list Arctostaphylos imbricata as threatened
(October 4, 1994; 59 FR 50550), stated that the San Bruno Mountain HCP,
a planning effort under management and implementation by San Mateo
County and their consultant, Thomas Reid and Associates, identifies A.
imbricata as a ``species of concern'' but that the HCP does not
identify any species-specific management actions for this species.
Since publication of the proposed rule, provisions of the HCP
pertaining to management for the conservation of A. imbricata have been
clarified. The HCP preserves most of the mountain and provides
monitoring and management for a number of rare plant and animal
species, including A. imbricata. In addition, threats identified in the
proposed rule pertaining to fire frequency and overutilization for
horticultural purposes are no longer considered to pose a significant
risk to the survival of the species. For these reasons, the Service now
believes the plant is adequately conserved.
Previous Federal Action
On December 15, 1980, the Service published in the Federal Register
an updated Notice of Review for plants
(45 FR 82480) which included Arctostaphylos imbricata as a category 1
candidate for Federal listing. Category 1 taxa were formerly defined as
taxa for which the Service had on file sufficient information on status
and threats to support issuance of a listing proposal. Arctostaphylos
imbricata retained category 1 status in revised plant notices published
on September 27, 1985 (50 FR 39526), February 21, 1990 (55 FR 6184),
and September 30, 1993 (58 FR 51144).
A proposal to list Arctostaphylos imbricata as threatened and
Lessingia germanorum as endangered was published in the Federal
Register on October 4, 1994 (59 FR 50550). This notice of withdrawal of
the proposal to list A. imbricata is published concurrently in the
Federal Register with the final rule listing L. germanorum as
endangered in order to resolve the listing status of both species.
Processing the final listing decisions on these two species follows the
Service's listing priority guidance published in the Federal Register
on December 5, 1996 (61 FR 64475).
Summary of Comments and Recommendations
In the October 4, 1994, proposed rule and associated notifications,
all interested parties were requested to submit factual reports or
information
[[Page 33389]]
that would contribute to the development of a final decision document.
Appropriate Federal and State agencies, county and city governments,
scientific organizations, and other interested parties were contacted
and requested to comment. In accordance with Service policy published
on July 1, 1994 (59 FR 34270), the Service solicited comments from
three appropriate and independent specialists regarding pertinent
scientific or commercial data and assumptions relating to the proposed
rule. A newspaper notice of the proposed rule was published in the San
Francisco Chronicle on October 19, 1994, which invited general public
comment. A 60-day comment period closed on December 4, 1994.
The Service received eight letters of comment. No requests for
public hearings were received. Because the proposed rule included both
Arctostaphylos imbricata and Lessingia germanorum, only comments
pertaining to A. imbricata are discussed here. Comments and issues
pertaining to L. germanorum are discussed in a separate Federal
Register notice published concurrently with this notice.
Of the eight people who submitted comments, three were neutral and
four supported the listing of Arctostaphylos imbricata. The eighth
respondent opposed the listing of A. imbricata on the grounds that
listing was premature at the time and recommended that it be retained
as a candidate species. As previously indicated, the listing proposal
for A. imbricata is being withdrawn in this notice. A candidate is a
species for which the Service has on file sufficient information on the
status and threats to the species to support issuance of a listing
proposal. Therefore, upon the withdrawal of the proposal to list, A.
imbricata cannot be maintained as a candidate.
One commenter indicated that designation of critical habitat would
aid in protection of rare plants. Because the proposed rule for
Arctostaphylos imbricata is being withdrawn, this issue is moot with
respect to this species. Another commenter suggested that the effects
of microwave facilities on San Bruno Mountain might pose a threat to
the species. The Service is not aware of any data to support this
contention and no evidence was provided by the commenter.
The combined threats of senescence (growing old, dying) of plants
and lack of reproduction due to the prolonged absence of fire described
in the proposed rule were considered by another commenter to be
unsubstantial. After reviewing the available information, the Service
concurs. More detail on this issue is provided in the discussion of
Factor E in the ``Summary of Factors Affecting the Species'' section
below.
Only one of the three independent and appropriate specialists
provided comments on the proposal to list Arctostaphylos imbricata.
This reviewer concurred with all of the comments made in the proposed
rule concerning the status, threats, and potential threats to the
species and supported listing as proposed. The reasons for the
Service's decision to withdraw its proposal to list A. imbricata, in
opposition to this specialist's recommendation, are explained in the
following section.
Summary of Factors Affecting the Species
Section 4(a)(1) of the Act requires the Service to consider five
factors when determining whether to list a species as threatened or
endangered. These factors, and their application to the Service's
decision to withdraw the proposal to list Arctostaphylos imbricata
Eastw. (San Bruno Mountain manzanita), are as follows:
A. The present or threatened destruction, modification, or
curtailment of its habitat or range. No threats to Arctostaphylos
imbricata were identified under this factor in the proposed rule, nor
were any such threats identified by commenters on the rule. None of the
colonies are threatened by development permitted under the San Bruno
Mountain HCP. The Service believes that no threats exist to the
species' habitat or range.
B. Overutilization for commercial, recreational, scientific, or
educational purposes. The proposed rule cited overutilization for
horticultural purposes as a potential threat to Arctostaphylos
imbricata. In 1991, cuttings were taken from plants located at
Kamchatka Point on San Bruno Mountain. The remnant surviving portions
of the plants showed evidence that the clippings were performed with
horticultural expertise (Doug Heisinger, Park Ranger, San Mateo County
Park, pers. comm. 1993). Some A. imbricata individuals being sold at
local plant sales may have originated from clippings from the natural
population (Paul Reeberg, pers. comm. 1993). The Service now concludes
that, although such actions are inappropriate and illegal (under both
the California Endangered Species Act and the California Native Plant
Protection Act), infrequent pruning does not currently constitute a
significant threat to the survival of the species.
C. Disease or predation. No known threats from disease or predation
were identified in the proposed rule. The Service has no new
information on threats from these factors.
D. The inadequacy of existing regulatory mechanisms. The proposed
rule stated that Arctostaphylos imbricata derived limited protection
from the San Bruno Mountain HCP, but that no species-specific
management actions for A. imbricata are identified in the HCP and none
have been implemented. After publication of the proposed rule, the HCP
Trustees informed the Service that the San Bruno Mountain HCP provides
for monitoring and management of populations of all rare plants
occurring on the mountain including A. imbricata. Moreover, the HCP
Trustees have agreed and committed to an annual budget for rare plant
monitoring and management. Any specific management activities
recommended, such as controlled burning (see Factor E below), will be
carried out under the HCP. Present management for A. imbricata includes
alien plant control. The Trustees have also expressed a willingness to
meet and work with Service biologists to identify and implement any
specific management actions necessary for the conservation of the
species (V. Harris, in litt. 1996).
Arctostaphylos imbricata is listed as endangered under the
California Endangered Species Act (Chapter 1.5 section 2050 et seq. of
the California Fish and Game Code and Title 14 California Code of
Regulations 670.2). The proposed rule stated that, although both the
California Endangered Species Act and the California Native Plant
Protection Act prohibit the ``take'' of State-listed plants (California
Endangered Species Act, Chapter 1.5 section 2080 and California Native
Plant Protection Act, Chapter 10 section 1908), State law exempts the
taking of such plants via habitat modification or land use changes by
the owner provided notification requirements are satisfied. The Service
concluded that this exemption renders State law inadequate to protect
A. imbricata from extinction. The Service believes that the inadequacy
of State law in protecting A. imbricata is no longer an issue because
protection of the species is provided by the San Bruno Mountain HCP.
E. Other natural or manmade factors affecting its continued
existence. The Service indicated in the proposed rule that
Arctostaphylos imbricata is a fire-adapted plant that, following a
fire, regenerates entirely from seed and does not resprout from a basal
burl. Keeley (1977) labeled plants employing this
[[Page 33390]]
type of post-fire reproductive strategy ``obligate-seeders.'' The
Service also implied in the proposed rule that fire, which can remove
competing vegetation and counter mechanisms that prevent seed
germination (e.g., hormones, impervious seed coat), is necessary for
the maintenance of A. imbricata because sexual reproduction by seed is
important to the maintenance of genetic diversity. Although germination
of its seed bank (seeds accumulated in the soil and canopy of mature
shrubs) is triggered mainly by fire, occasional germination and
establishment of A. imbricata does occur without the aid of fire (R.
Gankin, in litt., 1994). Moreover, A. imbricata can spread vegetatively
and reportedly is spreading on San Bruno Mountain (R. Gankin, in litt.,
1994). Thus, fire is not necessary for maintenance of the species.
The Service asserted in the proposed rule that if the amount of
time between fires were too long, Arctostaphylos imbricata would have
little opportunity to reproduce sexually and individuals could become
senescent. However, Keeley (1977) argued that the reproductive strategy
of obligate-seeders such as the non-sprouting manzanita species is an
adaptation to a long-interval fire cycle. Obligate-seeders tend to
occur in less fire-prone areas, like San Bruno Mountain which is often
shrouded in fog during the summer (D. Schooley, Bay Area Land Watch, in
litt., 1994), that generally burn more intensely when fires do occur
(Keeley 1977). Consequently, A. imbricata and other obligate-seeders
``are resilient to very long intervals [between fires] and successful
seedling recruitment is observed after fires in stands which may exceed
100 years of age'' (Keeley et al. 1988). In addition, fires burned
colonies of A. imbricata on San Bruno Mountain in 1964 and in the late
1980's. Even though all of the individuals in the colony which burned
in the 1980's were killed, significant regeneration did take place (R.
Gankin, in litt., 1994). Also, both regeneration from seed and
spreading by layering has occurred in the colony which burned in 1964
(D. Schooley, in litt., 1994). For these reasons, the Service concludes
that the prolonged absence of fire does not threaten A. imbricata now
and will not in the foreseeable future.
The Service also stated in the proposed rule that a reduction in
fire frequency could pose a threat to the species because periodic
fires reduce competition and shading by other plant species. On San
Bruno Mountain, Arctostaphylos imbricata grows on rocky exposed areas
such as open ridges. On such sites, the lack of soil development
precludes significant establishment of other plant species; the species
most likely to pose a threat through overtopping and consequent
shading, Ceanothus thrysiflorus, is a short-lived species that does not
do well on such undeveloped soils (R. Gankin, in litt., 1994). The
Service now concludes, on the basis of the foregoing evidence, that the
prolonged absence of fire is not likely to result in significant
establishment of other plant species and that therefore competition
from (including shading by) other plant species does not pose a
significant threat to the survival of A. imbricata.
Frequent fire, that is fire recurring within a short period of time
(fewer than 15 years), can result in local extinctions (Zedler et al.
1983 in Keeley and Keeley 1988). As discussed above and in the proposed
rule, on San Bruno Mountain Arctostaphylos imbricata grows on rocky
exposed areas such as open ridges. Because such open sites lack
sufficient fine fuels (i.e., dried grass and herbs) to sustain fire or
carry fire from adjoining, more densely vegetated habitat, the Service
concludes that fire is unlikely to occur frequently in A. imbricata
habitat and that, therefore, frequent fire is not a significant threat
to the species.
The Service has carefully assessed the best scientific and
commercial information available regarding the past, present, and
future threats faced by Arctostaphylos imbricata in determining to
withdraw the proposed rule to list the species as threatened. The
Service has determined that implementation of the San Bruno Mountain
HCP, which includes monitoring and management of A. imbricata,
sufficiently removes the threats to the species and provides for its
conservation. Furthermore, the Service has determined that the threats
identified in the proposed rule pertaining to fire frequency and
overutilization for horticultural purposes are not likely to pose a
significant risk to the survival of A. imbricata.
Author: The primary author of this document is Diane Windham,
Sacramento Field Office (see ADDRESSES section).
Authority: The authority for this action is section
4(b)(6)(B)(ii) of the Endangered Species Act of 1973, as amended (16
U.S.C. 1531 et seq).
Dated: April 8, 1997.
John G. Rogers,
Acting Director, U.S. Fish and Wildlife Service.
[FR Doc. 97-15926 Filed 6-18-97; 8:45 am]
BILLING CODE 4310-55-P