[Federal Register Volume 65, Number 33 (Thursday, February 17, 2000)]
[Proposed Rules]
[Pages 8104-8107]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-3652]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
Endangered and Threatened Wildlife and Plants; Notice of 90-Day
Finding for a Petition To List the Yellow-billed Cuckoo as Endangered
and Commencement of a Status Review
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Notice of 90-day petition finding.
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SUMMARY: We, the U.S. Fish and Wildlife Service (Service), announce a
90-day finding on a petition to list the yellow-billed cuckoo (Coccyzus
americanus) as endangered, with critical habitat, pursuant to the
Endangered Species Act (Act) of 1973, as amended. We find that the
petition presents substantial scientific or commercial information to
indicate that the listing of the yellow-billed cuckoo may be warranted.
Therefore, we are initiating a status review to determine if the
petitioned action is warranted. To ensure that the review is
comprehensive, we are soliciting information and data regarding this
species.
DATES: The finding in this document was made on February 7, 2000. To be
considered in the status review and subsequent 12-month finding for the
petition, your information and comments must be received by April 17,
2000.
ADDRESSES: You may submit data, information, comments, or questions
concerning this finding to the Field Supervisor, U.S. Fish and Wildlife
Service, Sacramento Fish and Wildlife Office, 2800 Cottage Way, Room W-
2605, Sacramento, California 95825. The petition finding, supporting
data, and comments are available for public inspection, by appointment,
during normal business hours at the above address.
FOR FURTHER INFORMATION CONTACT: Karen Miller at the Sacramento Fish
and Wildlife Office (see ADDRESSES section above), or at 916/414-6600.
SUPPLEMENTARY INFORMATION:
Background
Section 4(b)(3)(A) of the Endangered Species Act (Act) of 1973, as
amended (16 U.S.C. 1531 et seq.), requires that we make a finding on
whether a petition to list, delist, or reclassify a species presents
substantial information indicating that the petitioned action may be
warranted. To the maximum extent practicable, we must make this finding
within 90 days of the receipt of the petition and publish it promptly
in the Federal Register. If the finding is that substantial information
was presented, we are also required to promptly commence a review of
the status of the involved species. This finding is based on
information contained in the petition, supporting information submitted
with the petition, and information otherwise available to us at the
time the finding was made. While the Act does not provide for petitions
to designate critical habitat, the specific critical habitat
designation is petitionable under the Administrative Procedures Act. As
required by section 4(a)(3) of the Act, we will consider critical
habitat designation if we determine that listing is warranted.
The processing of this petition conforms with our Listing Priority
Guidance published in the Federal Register on October 22, 1999 (64
FR57114). The guidance clarifies the order in which we will process
rulemakings. Highest priority is processing emergency listing rules for
any species determined to face a significant and imminent risk to its
well-being (Priority 1). Second priority (Priority 2) is processing
final determinations on proposed additions to the lists of endangered
and threatened wildlife and plants. Third priority is processing new
proposals to add species to the lists. The processing of administrative
petition findings (petitions filed under section 4 of the Act) is the
fourth priority. The processing of this 90-day petition finding is a
Priority 4 action and is being completed in accordance with the current
Listing Priority Guidance.
We were previously petitioned to list the western yellow-billed
cuckoo (Coccyzus americanus occidentalis) in 1986 as endangered in the
States of California, Washington, Oregon, Idaho, and Nevada (Manolis et
al. 1986). We received this petition from Dr. Tim Manolis, Western
Field Ornithologists, and it was cosigned by the Animal Protection
Institute, Defenders of Wildlife, Sacramento River Preservation Trust,
Friends of the River, Planning and Conservation League, Davis
[[Page 8105]]
Audubon Society, Sacramento Audubon Society, and the Sierra Club. We
published a 90-day finding on January 21, 1987, in the Federal Register
(52 FR 2239) that the petition presented substantial information
indicating that the requested action may be warranted. We acknowledged,
in that finding, the difficulties in defining distinct, biologically
defensible populations of western yellow-billed cuckoos for possible
listing, and the existence of gaps in available information as to its
status in certain parts of its range. We published a 12-month finding
on December 29, 1988, in the Federal Register (53 FR 52746) that the
petitioned action was not warranted, finding that the petitioned area
did not encompass either a distinct subspecies or a distinct population
segment. The finding cited--(1) a study of geographic variation in the
species that concluded the morphological differences between eastern
and western birds were too small to merit separate subspecies (Banks
1988), and (2) that the petitioned area did not encompass a distinct
population segment. It noted that yellow-billed cuckoos near a State
line within the petitioned area, such as on the California side of the
lower Colorado River, are part of the same population and interbreed
with birds immediately across the same State border and outside the
petitioned area.
We received another petition on February 9, 1998, and dated
February 2, 1998, to list the yellow-billed cuckoo (Coccyzus
americanus) as an endangered species. The petition was submitted by
Robin Silver, Kieran Suckling, and David Noah Greenwald of Southwest
Center for Biological Diversity on behalf of 22 groups. The 22 groups
are the Maricopa Audubon Society, Tucson Audubon Society, Huachuca
Audubon Society, White Mountain Audubon Society, White Mountain
Conservation League, Wildlife Damage Review, Sky Island Alliance, San
Pedro 100, Zane Grey Chapter of Trout Unlimited, T and E Inc.,
Biodiversity Legal Foundation, Environmental Protection Information
Center, Sierra Nevada Alliance, Wetlands Action Network, Rangewatch,
Oregon Natural Desert Association, Oregon Natural Resources Center,
Klamath-Siskiyou Wildlands Center, Southern Utah Wilderness Alliance,
Wild Utah Forest Campaign, Friends of Nevada Wilderness, and Toiyabe
Chapter of the Sierra Club. The petitioners requested that we list the
yellow-billed cuckoo as endangered, stating that they believe the
yellow-billed cuckoo ``is endangered in a significant portion of its
range (i.e., the western United States).'' The petitioners also stated
they ``believe this range of endangerment is coterminous with a valid
subspecies, the western yellow-billed cuckoo (Coccyzus americanus
occidentalis)'' and that they would concur with a decision to list only
this subspecies. The petitioners also requested that critical habitat
be designated. Included in the petition was supporting information
relating to the species' taxonomy and ecology, adequacy of existing
regulatory mechanisms for the species, the historic and present
distribution, current status, and causes of decline in the western
United States. This notice announces our 90-day finding for the 1998
petition.
The yellow-billed cuckoo is a medium-sized bird of about 30
centimeters (12 inches) in length, and weighing about 60 grams (2
ounces). The species has a slender, long-tailed profile, with a fairly
stout and slightly down-curved bill, which is blue-black with yellow on
the basal half of the lower mandible (bill). Plumage is grayish-brown
above and white below, with rufous primary flight feathers. The tail
feathers are boldly patterned with black and white below. The legs are
short and bluish-gray, and adults have a narrow, yellow eye ring.
Juveniles resemble adults, except the tail patterning is less distinct,
and the lower bill may have little or no yellow. Males and females
differ slightly. Males tend to have a slightly larger bill, and the
white in the tail tends to form oval spots, whereas in females the
white spots tend to be connected and less distinct (Hughes 1999).
In the west, based on historic accounts, the species was widespread
and locally common in California and Arizona; locally common in a few
river reaches in New Mexico; common very locally in Oregon and
Washington; generally local and uncommon in scattered drainages of the
arid and semiarid portions of western Colorado, western Wyoming, Idaho,
Nevada, and Utah; and, probably uncommon and very local in British
Columbia. Hughes (1999) summarizes the species' historic range and
status in these areas. The species was listed by the State of
California as threatened in 1971 and was reclassified as endangered in
1987. Based on a 1986-87 statewide survey, only three areas in the
State support more than about five breeding pairs on a regular basis.
In the Pacific Northwest, the last confirmed breeding records were in
the 1930s in Washington and in the 1940s in Oregon. The species may now
be extirpated from Washington. Arizona probably contains the largest
remaining cuckoo population among States west of the Rocky Mountains,
but cuckoo numbers in 1999 are substantially less than some previous
estimates for Arizona as habitat has declined. In Colorado and Idaho,
the species is rare, and in Nevada, the remaining breeding populations
are threatened with extinction, if not already extirpated (Hughes
1999). The portion of Texas west of the Pecos River has been identified
as within the range of the historic western subspecies (Oberholser and
Kincaid 1974), but other authors consider birds from this area most
similar to eastern cuckoos (Hughes 1999). The species still occurs in
this area, but its conservation status is unknown (Groschupf 1987). The
species is widespread and uncommon to common in central and eastern
Texas (Oberholser and Kincaid 1974; Rappole and Blacklock 1994).
The species breeds from extreme southern Canada (Quebec and
Ontario) south to the Greater Antilles and Mexico (American
Ornithologist Union (AOU) 1998). The cuckoo occurs widely and is an
uncommon to common breeding bird in the United States east of the
Continental Divide. Habitat for the species in the eastern United
States, mainly riparian and other broad-leaved woodlands, is
widespread. This habitat is in contrast to habitat west of the
Continental Divide, where suitable habitat is limited to narrow, and
often widely separated, riparian patches. Distribution, population, and
trend data we obtained from the Breeding Bird Survey (BBS) program and
other available sources indicate that, although regional declines have
occurred, the yellow-billed cuckoo is relatively common as a breeding
bird in much of the eastern United States (Oberholser and Kincaid 1974;
Rappole and Blacklock 1994; BBS 1999; Hughes 1999).
The petitioners included information on factors affecting the
species in the western United States, which they define as the historic
range of the western subspecies. The petition identifies habitat loss,
overgrazing, tamarisk invasion of riparian areas, river management,
logging, and pesticides as causes of decline. These factors are
consistent with loss, degradation, and fragmentation of riparian
habitat as the primary factor causing yellow-billed cuckoo declines in
the western United States. Estimates of riparian habitat losses include
90-95 percent for Arizona, 90 percent for New Mexico, 90-99 percent for
California, and more than 70 percent nationwide (Noss et al. 1995;
Ohmart 1994). Much of the remaining habitat is in poor condition
[[Page 8106]]
and heavily affected by human use (U.S. Department of Interior 1994;
Almand and Krohn 1978). Local extinctions and low colonization rates
have also been identified as factors, and pesticides and loss of
wintering habitat as potential factors (Hughes 1999).
We reviewed the petition, supporting documentation, and other
information available in our files to determine if substantial
information is available to indicate that the requested actions may be
warranted. We find that the petition presents substantial information
indicating that listing a western yellow-billed cuckoo subspecies
(Coccyzus americanus occidentalis) may be warranted, although the
taxonomy of this subspecies is currently unclear. The petitioners
stated that ``all existing scientific data supports the AOU conclusion
that the western yellow-billed cuckoo is a valid sub-species.''
However, this statement does not represent the AOU's current position.
The AOU does not have a current position on the validity of yellow-
billed cuckoo subspecies and has stated the need to evaluate the
taxonomic standing of the subspecies of North American birds (AOU
1998). The AOU's Committee on Classification and Nomenclature (the body
that makes taxonomic decisions for North American birds) has begun a
comprehensive review of the taxonomic status of subspecies for North
American birds, a task that is expected to take at least several years
(Richard C. Banks, U.S. National Museum of Natural History, chair of
AOU Committee on Classification and Nomenclature (North America), pers.
comm., 1999). The existing scientific data, including that provided by
the petitioners, is equivocal (of uncertain significance) on the
taxonomic status of western yellow-billed cuckoo subspecies.
The yellow-billed cuckoo was separated into eastern (Coccyzus
americanus americanus) and western (Coccyzus americanus occidentalis)
subspecies by Ridgway (1887), who cited a larger average size for birds
from the western versus eastern United States. Several ornithologists
who have questioned the validity of these subspecies since that time
(Todd and Carriker 1922; Swarth 1929; Van Tyne and Sutton 1937; Bent
1940; Monson and Phillips 1981) noted the small magnitude and
inconsistency of differences between eastern and western cuckoos and
the broad overlap in the size of eastern and western individuals. The
yellow-billed cuckoo has been the subject of two taxonomic studies
published since 1980. One study concluded that the division of yellow-
billed cuckoos into two subspecies was not supported by the
morphological data and that all yellow-billed cuckoos in North America
should be classified simply as C. americanus (Banks 1988, 1990). The
second study found small but statistically significant size differences
between western and eastern cuckoos (Franzreb and Laymon 1993). This
study stated that the recognition of subspecies on the basis of these
differences was equivocal (of uncertain significance) and recommended
that the subspecies described by Ridgway (1887) be retained, pending
further studies (Franzreb and Laymon 1993).
The petitioners cited the above studies' findings of statistically
significant differences in morphological measurements between western
and eastern cuckoos, but did not provide evidence that these
differences meet traditional or other accepted criteria for defining
avian subspecies. Banks (1988, 1990) concluded that these differences
were not adequate for subspecies recognition. The petition and other
information currently available to us do not resolve this taxonomic
question for this species. However, we are funding ongoing genetic work
that may aid in resolving this issue. Although the available
information does not conclusively resolve this issue, we find that the
petition presents substantial information that leads us to conclude
that further investigation is required, through a status review, to
determine if listing the western yellow-billed cuckoo as a subspecies
is warranted.
The petitioners stated that they believed the western States
constitute a significant portion of the species' range. However, we
find that the petition does not provide information to support this
statement. The petition does not provide information on the
conservation status of the yellow-billed cuckoo outside the western
United States and British Columbia, Canada, and the available data do
not indicate that the species as a whole may be threatened or
endangered in a significant portion of its range. On a gross level, the
area of the western States within the species' historic range
represents about 27 percent of the total area within the species' U.S.
range. However, this number includes the entire area of States and does
not represent the distribution or area of habitat suitable or available
for the species. The species nests almost exclusively in riparian
habitats in the west and occurs widely in riparian habitats in the east
(Hughes 1999). More than 95 percent of the riparian habitat area within
the species' U.S. range is located east of the Continental Divide, and
less than 5 percent is located west of the divide. Further, these
percentages overestimate the proportion of cuckoo habitat occurring
west of the Continental Divide, as they do not account for the fact
that, east of the divide, the cuckoo also nests in a variety of
nonriparian habitats, including woodlands, hardwood forests, abandoned
farmlands, fencerows, shade trees, and gardens (Hughes 1999).
Although not specifically addressed by the petitioners, we also
considered whether substantial information exists indicating that
listing of the western yellow-billed cuckoo as a distinct population
segment (DPS) as described in our 1996 Policy Regarding the Recognition
of Distinct Vertebrate Population Segments Under the Endangered Species
Act (61 FR 4721) may be warranted. The policy states that we will
consider three elements in decisions regarding the status of a possible
DPS as endangered or threatened under the Act: (1) Distinctness of a
population segment in relation to the remainder of the species to which
it belongs, (2) significance of the population segment in relation to
the species as a whole, and (3) conservation status of the population
segment in relation to the Act's standards for listing as threatened or
endangered. Criteria for all three elements must be satisfied to be
considered a DPS.
Anecdotal reports have suggested differences between eastern and
western birds based on bill color and vocalizations (Franzreb and
Laymon 1993), but these differences have not been documented. Western
cuckoos have been reported to nest later, on average, than eastern
cuckoos (Franzreb and Laymon 1993; Hughes 1999), but the species
demonstrates considerable plasticity in timing of nesting (Hamilton and
Hamilton 1965; Hughes 1999). These observed differences could represent
distinct populations with genetically based adaptations to local
conditions, however, equally plausible alternative explanations exist.
For example, the observed differences could also represent the
interaction between individuals of a relatively uniform but flexible
species and local environmental factors. We are not currently aware of
any study that has tested the alternative explanations, although the
principal study of nesting biology published in a scientific journal
(Hamilton and Hamilton 1965) favored the latter interpretation
(differences are due to interactions of individuals of a flexible
species). This study questioned whether eastern and western cuckoos
were distinct, based on observations of
[[Page 8107]]
ecology, adaptation to the physical environment, and timing and
duration of breeding season. Based on the available scientific
information, it is unclear that eastern and western yellow-billed
cuckoos are distinct. However, we find that the petition presents
substantial information that leads us to conclude that further
investigation is required, through a status review, to determine if
listing the western yellow-billed cuckoo as a distinct population
segment may be warranted.
In making these findings, we recognize that yellow-billed cuckoo
populations have declined in portions of their range in the United
States, particularly west of the Continental Divide. Loss and
degradation of western riparian habitats appears to be a primary factor
in these declines. The range of the species has contracted
substantially in many regions of the western United States, compared to
the range reported for the species in the first several decades of the
twentieth century (Gaines and Laymon 1984; Laymon and Halterman 1987;
Hughes 1999). Population numbers have also declined substantially in
the western United States (Hughes 1999), although scientific data on
the magnitude of population changes are unavailable for most regions.
Public Information Solicited
We solicit information regarding the taxonomic status, occurrence,
and distribution of the species, and any additional data or scientific
information from the public, scientific community, Tribal, local,
State, and Federal governments, and other interested parties concerning
the status of the yellow-billed cuckoo. Of particular interest is
information regarding:
(1) The taxonomy and genetics of the species and whether this
information supports classifying the western yellow-billed cuckoo as a
valid subspecies;
(2) Behavioral and ecological differences between eastern and
western yellow-billed cuckoos; and
(3) Significance of the western population in relation to the
species as a whole that may aid in differentiating population segments.
After consideration of additional information received during the
public information collection period (see DATES section of this
notice), we will prepare a 12-month finding as to whether listing the
yellow-billed cuckoo as a species, subspecies, or distinct population
segment is warranted.
References Cited
You may request a complete list of all references we cited, as well
as others, from the Sacramento Fish and Wildlife Office (see ADDRESSES
section).
Authority. The authority for this action is the Endangered Species
Act of 1973, as amended (16 U.S.C. 1531 et seq.).
Dated: February 7, 2000.
Jamie Rappaport Clark,
Director, U.S. Fish and Wildlife Service.
[FR Doc. 00-3652 Filed 2-16-00; 8:45 am]
BILLING CODE 4310-55-P