[Federal Register: February 16, 1999 (Volume 64, Number 30)]
[Proposed Rules]               
[Page 7587-7601]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]



Fish and Wildlife Service

50 CFR Part 17

RIN 1018-AF35

Endangered and Threatened Wildlife and Plants: Proposed 
Threatened Status for the Mountain Plover

AGENCY: Fish and Wildlife Service, Interior.

ACTION: Proposed rule.


SUMMARY: The Fish and Wildlife Service (Service) proposes to list the 
mountain plover (Charadrius montanus) as a threatened species pursuant 
to the Endangered Species Act (Act) of 1973. The mountain plover is a 
bird of shortgrass prairie and shrub-steppe landscapes at both breeding 
and wintering locales. Breeding occurs in the Rocky Mountain States 
from Canada south to Mexico with most breeding birds occurring in 
Montana and Colorado. Most wintering birds occur on grasslands or 
similar landscapes in California; fewer wintering birds occur in 
Arizona, Texas, and Mexico. Breeding Bird Survey trends analyzed for 
the period 1966 through 1996 document a continuous decline of 2.7 
percent annually for this species, the highest of all endemic grassland 
species. Between 1966 and 1991, the continental population of the 
mountain plover declined an estimated 63 percent. The current total 
population is estimated to be between 8,000 and 10,000 individuals. 
Conversion of grassland habitat, agricultural practices, management of 
domestic livestock, and decline of native herbivores are factors that 
likely have contributed to the mountain plover's decline. Pesticides 
may be a factor contributing to the decline of mountain plovers, but 
their effects are not completely understood.

DATES: We must receive comments from all interested parties by April 
19, 1999. We must receive requests for public hearings by April 2, 

ADDRESSES: Send comments and materials concerning this proposal to the 
Assistant Field Supervisor, U.S. Fish and Wildlife Service, 764 Horizon 
Drive, South Annex A, Grand Junction, Colorado 81506-3946. We will make 
comments and materials we receive available for public inspection, by 
appointment, during normal business hours at the above address.

FOR FURTHER INFORMATION CONTACT: Robert Leachman at the above address, 
telephone 970/243-2778; facsimile 970/245-6933.



    The mountain plover (Charadrius montanus) was described by John K. 
Townsend in 1837 from specimens collected near the Sweetwater River, 
Fremont County, Wyoming (Coues 1874, cited in Laun 1957). This species 
was originally named the Rocky Mountain plover because the first 
specimens were taken within sight of those mountains (Oberholser 1974). 
The mountain plover has since been known by several different 
scientific names, as well as other common names. The species name 
Charadrius montanus was formally adopted by the Committee on 
Classification and Nomenclature of the American Ornithological Union in 
1983 (R. Banks, National Biological Service, pers. comm., 1994). There 
are no subspecies (Oberholser 1974).
    The mountain plover is a small bird (about 17.5 centimeters (cm)) 
(7 inches)(in)), about the size of a killdeer (Charadrius vociferus). 
It is light brown above with a lighter colored breast, but lacks the 
contrasting dark breastbelt common to many other plovers. During the 
breeding season it has a white forehead and a dark line between the 
beak and eye, which contrasts with the dark crown. Mountain plovers are 
insectivorous, with beetles, grasshoppers, crickets, and ants their 
principal food items (Stoner 1941, Baldwin 1971, and Rosenberg et al. 
1991, Knopf 1998).
    The mountain plover is associated with shortgrass and shrub-steppe 
landscapes throughout its breeding and wintering range. Historically, 
on the breeding range, it occurred on nearly denuded prairie dog towns 
(Knowles et al. 1982, Olson-Edge and Edge 1987) and in areas of major 
bison concentrations (Knopf 1997). Many consider nesting mountain 
plovers to be strongly associated with prairie dog towns (Tyler 1968, 
Knowles et al. 1982, Knowles and Knowles 1984, Shackford 1991, Samson 
and Knopf 1994, Knopf 1996b). All of the endemic grassland birds 
evolved within a grassland mosaic of lightly, moderately, and heavily 
grazed areas, and mountain plovers are considered to be strongly 
associated with sites of heaviest grazing pressure, to the point of 
excessive surface disturbance (Knopf and Miller 1994, Knopf 1996b). 
Currently, the mountain plover is also attracted to man-made landscapes 
(e.g., sod farms, cultivated fields) that mimic the natural habitat 
associations, or sites with grassland characteristics (alkali flats, 
other agricultural lands).
    Nesting mountain plovers are reported in some of the Rocky Mountain 
and Great Plains States from Canada south to Texas, and possibly in 
Mexico. Most mountain plovers breed in Colorado and Montana; breeding 
also occurs in Wyoming, New Mexico, Arizona, Nebraska, Utah, Kansas, 
Oklahoma, and Texas. Breeding is suspected in Mexico and historic 
nesting records occur from Canada. Nesting habitat in Canada is 
restricted to southeastern Alberta and southwestern Saskatchewan. 
Breeding adults, nests, and chicks have been observed on cultivated 
lands in Colorado, Kansas, Nebraska, Oklahoma, and Wyoming. Most 
mountain plovers winter in California where they are found on 
grasslands or landscapes resembling grasslands, and cultivated fields; 
many fewer wintering plovers are reported from Arizona, Texas, and 
    The mountain plover is one of nine bird species endemic to the 
North American grasslands (Knopf 1996a). Endemic grassland birds have 
declined more rapidly than other species in North America, and the 
mountain plover's decline is greater than that of the other grassland 
endemics (Knopf 1994; Sauer et al. 1997). Unlike other plovers, 
mountain plovers are rarely found near water.

Habitat Characteristics

    Mountain plovers evolved on grasslands that were inhabited by large 
numbers of nomadic grazing ungulates such as bison (Bison bison), elk 
(Cervus elaphus), pronghorn (Antilocapra americana), and burrowing 
mammals such as kangaroo rats (Dipodomys sp.), prairie dogs (Cynomys 
sp.), and badgers (Taxidea taxus) (Knopf 1996a). The herbivores 
dominated the grassland landscape at both breeding and wintering sites, 
and their grazing, wallowing, and burrowing activities created and 
maintained a mosaic of vegetation and bare ground to which mountain 
plovers became adapted (Dobkin 1994, Knopf 1996a).
    Short vegetation, bare ground, and a flat topography are now 
recognized as habitat-defining characteristics at both breeding and 
wintering locales (Graul 1975, Knopf and Miller 1994, Knopf and Rupert 
1995). Mountain plovers nesting

[[Page 7588]]

sites are dominated by short vegetation and bare ground, often with 
manure piles or rocks nearby. Mountain plovers historically nested on 
black-tailed prairie dog (Cynomys ludovicianis) towns (Flowers 1985, 
Godbey 1992, Kantrud and Kologiski 1982, Knowles et al. 1982, Knowles 
and Knowles 1993) or other areas heavily grazed by prairie herbivores.
    Currently, in addition to nesting on prairie dog towns, mountain 
plovers show a strong affiliation for sites that are heavily grazed by 
domestic livestock (e.g. near stock watering tanks), and also attempt 
breeding on fallow and cultivated fields which mimic natural habitats 
(Knopf 1996b). In California, many of the preferred wintering sites are 
grazed by domestic livestock, or are within giant kangaroo rat 
(Dipodomys ingens) precincts or California ground squirrel 
(Spermophilus beecheyi) colonies (Knopf and Rupert 1995). Wintering 
mountain plovers in Mexico are almost entirely associated with prairie 
dog towns (N. Kaufman, U.S. Fish and Wildlife Service, in litt., 1998). 
Since mountain plovers are usually associated with sites that are 
modified by grazing and digging mammals, Knopf and Miller (1994) 
suggested classifying the mountain plover as a species more closely 
associated with disturbed prairie sites, rather than pristine prairie 
    Bison and elk are now functionally extirpated from all mountain 
plover breeding habitat, and numbers of pronghorn are greatly reduced. 
Similarly, prairie dog and/or kangaroo rat numbers are greatly reduced 
on mountain plover breeding and wintering sites. Now, the primary 
grazer on both breeding and wintering habitat is domestic livestock, 
although prairie dogs and/or giant kangaroo rats influence habitat 
locally at a few sites. Current domestic livestock grazing management 
emphasizes rotating the animals in time and space among allotments 
within fenced pastures (Dobkin 1994, Knopf 1996c). Currently accepted 
domestic livestock grazing management may cause grasses to become more 
dense and uniform in height, decrease the amount of bare ground, 
increase the abundance of shrubs, and reduce the frequency and effects 
of fire (Knopf and Rupert in press, Dobkin 1994). Therefore, some types 
of domestic livestock grazing management techniques do not result in 
the same habitat characteristics as those created by the native 
herbivores, with which the mountain plover evolved.

Life History

    Mountain plovers arrive on their breeding grounds by late March. 
The nest is a simple scrape on the ground which is lined with organic 
debris (Graul 1975). Nests typically occur in areas with vegetation 
less than 10 cm (4 in) in height, with at least 30 percent bare ground, 
and with a conspicuous object such as a manure pile, clump of forbs, or 
rock nearby (Graul 1975, Knopf and Miller 1994, Olson and Edge 1985, 
Knowles and Knowles 1998). Although short vegetation, bare ground, and 
an object are characteristic of nest sites, the presence of some taller 
vegetation to shade chicks and adults also has been reported as 
necessary (Shackford and Leslie 1995a). Nest sites occur on ground with 
less than 5 percent slope, which is usually heavily grazed by domestic 
livestock and/or prairie dogs (Graul 1973, Kantrud and Kologiski 1982, 
Knowles and Knowles 1998). Vegetation at nest sites throughout the 
breeding range is variable, but usually dominated by needle-and-thread 
(Stipa comata), blue gramma (Bouteloua gracilis), buffalo grass 
(Buchloe dactyloides), plains prickly pear cactus (Opuntia polycantha), 
June grass (Koeleria cristata), and sagebrush (Artemisia sp.) (Graul 
1975, Parrish 1988, Day 1994, Knowles and Knowles 1998).
    On the Colorado breeding grounds, flocks of mountain plovers begin 
to form as early as mid-June prior to migration to wintering habitat. 
The flocks increase in size until mid-August, and then depart for the 
wintering grounds between August and October (Graul 1975). Mountain 
plovers begin to arrive on wintering grounds in California by 
September, but do not appear in large numbers until November (Jurek 
1973; Knopf and Rupert 1995). Two mountain plovers that were color 
banded in Colorado in 1992 were seen in the San Joaquin Valley of 
California the same year, representing the first direct link between 
breeding and wintering habitat for the species (Knopf and Rupert 1995). 
A mountain plover banded as a chick in Phillips County, Montana, in 
1995, was seen in the Sulphur Springs Valley of Arizona on January 1, 
1998, supporting other indications that the fall migration to wintering 
habitat is less direct than migration to breeding grounds (F. Knopf, 
USGS-Biological Resources Division, pers. comm. 1998, Knopf and Rupert 
    Historically, the mountain plover has been reported from a variety 
of habitats during the wintering period, including grasslands and 
agricultural fields in California (Tyler 1916; Grinnell et al. 1918; 
Belding 1879 in Grinnell et al. 1918: Preston 1981 in Moore et al. 
1990; Werschkull et al. 1984 in Moore et al. 1990). More recently, 
mountain plovers are reported from natural, noncultivated sites such as 
alkali sink scrub, valley sink scrub, alkali playa, and annual 
grasslands (S. Fitton, Bureau of Land Management (BLM), in litt., 1992, 
Knopf and Rupert 1995) in the Central Valley. Although cultivated land 
is used by wintering mountain plovers and is more abundant than 
noncultivated land, Knopf and Rupert (1995) found that mountain plovers 
preferred alkali flats, burned grasslands, and grazed annual grasslands 
to cultivated sites. Grazing on such grassland sites was usually by 
domestic livestock or burrowing mammals (Knopf and Rupert 1995).
    Mountain plovers are gregarious on their wintering habitat. Flock 
size averages from about 20 to 180 individuals, increasing in size as 
spring migration approaches (Knopf and Rupert 1995). Flocks with up to 
1,100 individuals have been reported from the San Joaquin Valley and 
Imperial Valley (B. Radke, Service, in litt. 1992, Knopf and Rupert 
1995). Mountain plovers begin leaving wintering areas by mid-March and 
may make a nonstop migration to breeding grounds (Knopf and Rupert 
1995). In general, mountain plovers spend about 4 months on breeding 
grounds, 5 months on wintering habitat, and the remaining time mostly 
in their fall migration (Knopf and Rupert 1996).

Breeding Distribution and Abundance

    As discussed by Knopf (1996), the continental breeding range of the 
mountain plover has been reduced from its historical extent, especially 
in the eastern portion of the range. The mountain plover was formerly 
common in western and central Kansas (Goss 1891), and reported as 
numerous between Fort Supply, Oklahoma and Dodge City, Kansas (McCauley 
1877). The species is considered to have been historically numerous in 
Colorado (Bailey and Niedrach 1965) and Wyoming (Knight 1902). Mountain 
plovers formerly occupied western South Dakota (South Dakota 
Ornithologist's Union 1991) and Nebraska (Knopf 1996), and there is one 
known breeding reference in North Dakota (Roosevelt 1885). They may 
have bred in northern Mexico in 1901 (Sanford et al. 1924).


    Mountain plovers have been studied more intensively in Weld County 
than any other location throughout their range. Graul and Webster 

[[Page 7589]]

considered Weld County the breeding stronghold for the mountain plover, 
a conclusion widely referenced by subsequent authors (e.g., Knopf and 
Rupert 1996). Inventories completed by the Colorado Bird Atlas 
Partnership from 1987 through 1995 reported mountain plovers from 8 
percent of the survey blocks inventoried in eastern Colorado, and the 
number of mountain plover sightings in some survey blocks was nearly 
equal to or greater than those reported from Weld County (H. Kingery, 
Colorado Bird Atlas Partnership, pers. comm., 1994, in litt., 1998). 
Kingery (in litt., 1997) estimated that about 7,000 mountain plovers 
breed in Colorado, and that about 1,500 of those breed in Weld County.
    Shackford and Leslie (1995b) reported mountain plovers seen on 
cultivated fields in 14 counties in eastern Colorado from 1992 through 
1995, with most birds seen in Kiowa County. Adult mountain plovers also 
occur on cultivated fields in Las Animas County within the boundary of 
the Comanche National Grassland in southeast Colorado (J. Cline, U.S. 
Forest Service, in litt., 1994). Breeding mountain plovers also have 
been reported from southeast Colorado by other researchers (Chase and 
Loeffler 1978; Nelson 1993; R. Estelle, no affiliation, in litt.. 
1994). Carter et al. (1996) detected mountain plovers at very low 
densities in 10 Colorado Counties; mountain plovers were most numerous 
in Kiowa and Park Counties. The Colorado Natural Heritage Program 
conducted mountain plover surveys in Park County in 1994, 1995, and 
1997 (Pague and Pague 1994, Sherman et al. 1996, Hanson 1997). About 
1,000 mountain plovers were estimated in Park County in 1995, and these 
surveys also disclosed the vulnerability of some breeding sites to 
ongoing and potential urbanization (Sherman et al. 1996). Additionally, 
Service biologists have observed adults in Moffat County in July (R. 
Leachman, Service, pers. comm., 1998).
    The Bird Atlas Partnership survey (H. Kingery, in litt., 1998) and 
the inventory of cultivated fields (Shackford and Leslie 1995b) 
mentioned above resulted in observations of breeding behavior and 
relative abundance, not estimates of density or productivity. Knopf 
(1996) reported densities of breeding birds on the Pawnee National 
Grassland (Weld County) as ranging between 2.0 and 4.7 birds/square 
kilometer (km) between 1990 and 1994. In 1995, the Pawnee National 
Grassland experienced exceptionally wet, cold weather through June and 
few birds were found there during the breeding season (Knopf 1996). 
Sherman et al. (1996) estimated 1.32 birds/square km in Park County 
during 1995.
    Estimates of nest success and productivity in Colorado are 
available from studies on prairie habitat in Weld County and cultivated 
lands in southeast Colorado. Nest success on the Pawnee National 
Grassland in Weld County was highly variable among years. Percentage of 
nests where at least one egg hatched varied from 26 percent (Knopf and 
Rupert 1996) to 65 percent (Graul 1975). Mountain plovers in Weld 
County fledged an estimated 1.4 young/nest during 1969-1974 (Graul 
1975) and also in 1992, suggesting that breeding success in Weld County 
did not change much in nearly 30 years (Miller and Knopf 1993). 
McCaffery et al. (1984) estimated a brood size of about 1.3 chicks/
adult in Weld County just prior to fledging. Knopf (1996) hypothesized 
that reported low fledging rates were attributable to drought, which 
affects the food supply and simultaneously increases predation 
pressures. The only other estimate of productivity in Colorado is from 
mountain plovers on cultivated fields in southeast Colorado, southwest 
Kansas, and northwest Oklahoma where Shackford and Leslie (1995a) 
estimated 34 percent of nests were successful and 47 percent of chicks 
that hatched also fledged. In comparison, on the Pawnee National 
Grassland, an estimated 50 percent of nests were successful and 47 
percent of chicks that hatched also fledged (Miller and Knopf 1993). 
Further studies are needed to determine if average productivity and 
recruitment on cultivated land differs significantly from native 
grassland. In Weld County 60 to 70 percent of the mountain plover 
habitat occurs on the Pawnee National Grassland (F. Knopf, in litt. 
1991). We therefore believe that areas within Weld County will be 
important to any future conservation efforts because mountain plovers 
have shown an affinity for this locale, independent studies over a 30 
year period have confirmed successful reproduction, and the extensive 
Federal ownership improves opportunities for habitat maintenance and 
    Recent reports of the mountain plover being more widely distributed 
in Colorado than previously known has led to some speculation that the 
population in Colorado is stable or improving. Pulliam (1988) expressed 
caution that basing a species' conservation needs on where it is most 
common rather than where it is most productive may lead to errors. 
Although additional sightings of mountain plovers in Colorado are 
encouraging, some of these sightings have occurred on cultivated lands. 
We know of no productivity estimates that are available to compare 
production on these cultivated areas with production estimated from 
historic breeding sites.


    Breeding habitat for mountain plovers in Montana is usually 
characterized by grasslands and shrublands consisting commonly of 
needle-and-thread, blue grama, June grass, saltbush (Atriplex 
gardneri), and prickly pear cactus. Most breeding sites are grazed by 
domestic livestock or prairie dogs, and the largest number of breeding 
mountain plovers in Montana is found on a large complex of black-tailed 
prairie dog towns in Phillips and Blaine Counties (Knowles and Knowles 
1998). The prairie dog towns occur on the Charles M. Russell National 
Wildlife Refuge, Fort Belknap Indian Reservation, BLM, State school 
lands, and private lands. Mountain plovers in these two Counties number 
fewer than 2,000 individuals, and are considered the second major 
breeding population for the species (Knopf and Miller 1994, Knowles and 
Knowles 1996, S. Dinsmore, Service, pers. comm., 1998).
    Mountain plovers also breed on land administered by the BLM in 
Valley County (Little Beaver Creek), and on private land in Wheatland 
and Golden Valley Counties near the Little Belt and Big Snowy Mountains 
(Knowles and Knowles 1998). Surveys through 1997 now also confirm 
breeding mountain plovers in Big Horn, Broadwater, Carbon, Carter, 
Fergus, Jefferson, Hill, Madison, Musselshell, Petroleum, Rosebud, 
Toole, Treasure, and Teton Counties (Knowles and Knowles 1996, 1998; J. 
Grensten, BLM, pers. comm., 1998).
    Only one mountain plover was located during a search of cultivated 
fields in 17 counties in Montana in 1995, and mountain plovers appear 
to use cultivated fields only for foraging and territorial display; 
nesting has not been observed in cultivated fields in Montana (C. 
Knowles, Fauna West, pers. comm., 1998). Shackford and Leslie (1995b) 
hypothesized that more frequent disturbance of fields, a shorter 
growing season, and more clayey soils in Montana compared to Colorado 
(Knowles pers. comm., 1998) may explain the fact that fewer birds are 
sighted nesting on cultivated fields.
    With the exception of the population in Phillips and Blaine 
Counties, mountain plovers total less than 800 individuals at the other 
8 locations. Therefore, Knowles and Knowles (1996) estimate fewer than 
2,800 mountain plovers in Montana. Selected prairie-dog towns at the 
Charles M. Russell National Wildlife Refuge in Montana

[[Page 7590]]

yielded density estimates of 6.8 and 5.8 birds/square km in 1991 and 
1992, respectively. The spring of 1995 was very wet in Montana, and 
densities in this area were reported at 1.3 birds/square km in that 
year (Knopf 1996).


    The mountain plover is classified as common in Wyoming, with 
breeding known or suspected in 20 of 28 blocks of latitude/longitude. 
Six blocks in the southeast corner of the State make up the primary 
breeding range (Oakleaf et al. 1982). From 1992 to 1997, nesting was 
confirmed on the Thunder Basin National Grassland in northeast Wyoming 
with nearly all nests found on black-tailed prairie dog towns 
(Bartosiak 1992; M. Edwards, Forest Service, in litt., 1994; T. Byer, 
Forest Service, in litt., 1997). Based on 1997 survey data, about 150 
mountain plovers occur on the Grassland (T. Byer, in litt., 1997). 
Recently, Thunder Basin National Grassland acquired an adjacent parcel 
of privately-owned rangeland, which together with existing property 
forms a management unit that has been identified as the next potential 
site for black-footed ferret reintroduction. In addition, the current 
Forest Management Plan for Thunder Basin is being revised and the new 
plan will identify increased acreage to be managed specifically for 
prairie wildlife, such as prairie dogs and mountain plovers (M. 
Lockhart, U. S. Fish and Wildlife Service, pers. comm., 1998).
    From 1979 to 1992, nesting was confirmed at the Antelope Coal Mine 
in the southern Powder River Basin. Reported breeding densities of 0.9 
to 2.4 birds/square km are lower than those reported for Wyoming prior 
to 1965 and at other breeding sites in Montana and Colorado (Oelklaus 
1989, Parrish 1988, M. Edwards, in litt., 1994). Mountain plovers 
throughout the southern Powder River Basin are generally thought to be 
widely scattered at low densities, with a few areas of local 
concentrations (Oelklaus 1989). Knopf (in litt., 1991) found mountain 
plovers on the Laramie Plains, on the Chapman Bench north of Cody, and 
in the vicinity of Shirley Basin. One nest and some adults were located 
on cultivated lands in Laramie County (Shackford and Leslie 1995b). 
Mountain plovers also breed in shrub-steppe habitat in southwest 
Wyoming (Oakleaf et al. 1982). Recent survey efforts in Wyoming have 
not been as intensive as those in Montana or Colorado. In 1991, Knopf 
(in litt., 1991) estimated fewer than 1,500 mountain plovers nesting in 

New Mexico

    Historic reports from New Mexico indicate that mountain plovers 
numbered from several individuals (1968 to 1977 data) to 150 in a 
single flock in July 1937 (Hubbard 1978). Sager (1996) conducted 
mountain plover surveys in 1995 and found 152 breeding adults and 26 
juveniles at 35 sites in 11 counties north of 34 degrees latitude. His 
search was primarily confined to areas north of 34 degrees latitude. 
However, one adult was located in Hidalgo County during 4 days of 
survey effort south of 34 degrees, suggesting that occasional breeding 
may occur in the southern parts of the State (Sager 1996). Migrating 
mountain plovers were also sighted in Valencia, Colfax, Union, and 
Torrance Counties, with most of these seen on turf farms at Moriarty 
and Los Lunas (Sager 1996). The recent surveys in New Mexico imply that 
additional searching may yield more mountain plovers (S. Williams III, 
New Mexico Department of Game and Fish, in litt., 1997).


    Few breeding mountain plovers were found in Oklahoma native 
shortgrass prairie and prairie dog towns in 1986. The few plovers 
found, combined with the discovery of one mountain plover nest on a 
maize field, stimulated additional surveys of cultivated fields in 
Oklahoma (Shackford 1991). In Cimarron County in the panhandle of 
Oklahoma, Shackford (1991) found that during the nesting seasons of 
1986-1990, 60 percent of mountain plovers observed were in native 
grassland and 40 percent were in cultivated fields. Ten of the 15 birds 
observed in native grassland were on prairie-dog towns. Annual counts 
of mountain plovers on cultivated fields from 1990 through 1995 have 
ranged from 3 to 428 (Shackford and Leslie 1995b).

Other Breeding Areas

    In Utah, the only site known to have breeding mountain plovers is 
in Duchesne County, south of Myton, in the Uintah Basin. Counts of 
breeding mountain plovers in this area from 1992 through 1997 have 
ranged from 7 to 29, and broods have been found in each year except 
1992 (T. Dabbs, BLM, in litt., 1997). Counts of breeding mountain 
plovers on cultivated lands in western Kansas from 1992 through 1995 
have ranged from 52 (6 counties searched) to 114 (4 counties searched) 
(Shackford and Leslie 1995b). Surveys of cultivated fields and 
rangelands within the boundary of the Cimarron National Grassland in 
Kansas also have been conducted. Counts on the Grassland in 1994, 1996, 
and 1997 ranged from 1 to 13, and most of the sightings were on plowed 
fields (J. Chynoweth, Forest Service, in litt., 1997).
    Three pairs of mountain plovers were reported near Fort Davis, 
Texas, in 1992 (K. Brian, Davis Mountain State Park, pers. comm., 
1992), but more recent breeding in Texas cannot be confirmed due to 
lack of permission to access private land (P. Horner, Texas Parks and 
Wildlife Department, in litt., 1997). An adult incubating three eggs 
was found near Springerville, Apache County, Arizona, in May 1996 (T. 
Cordery, U.S. Fish and Wildlife Service, pers. comm., 1998). A nesting 
mountain plover was found in western Nebraska in 1990 (F. Knopf, in 
litt., 1990), and two mountain plover nests were found in a fallow 
field in the same vicinity in 1997 (W. Jobman, Service, in litt., 
1997). Seventeen mountain plovers were counted on 10 cultivated fields 
in western Nebraska in 1992 and 1995 (Shackford and Leslie 1995b). The 
most recent nesting record in Canada is one nest in southeastern 
Alberta in 1990 (C. Wershler, Sweetgrass Consultants Limited, pers. 
comm., 1992). Mountain plover breeding behavior was observed in 1998 in 
Nuevo Leon, Mexico, but additional surveys are needed to confirm nests 
and broods (F. Knopf, in litt., 1998). The Service is not aware of any 
breeding records from other locations.

Winter Distribution

    Historically, mountain plovers have been observed during the winter 
in California, Arizona, Texas, and Nevada; the California coastal 
islands of San Clemente Island, Santa Rosa Island; and, the Farallon 
Islands (Strecker 1912; Swarth 1914; Alcorn 1946; Jurek 1973 Jorgensen 
and Ferguson 1984; Garrett and Dunn 1981; B. Deuel, American Birds 
Editor, in litt., 1992). In Mexico, wintering mountain plovers have 
been sighted in Baja, California, as well as north-central and 
northeastern Mexico, specifically in Chihuahua, Coahuila, Sonora, Nuevo 
Leon, and San Luis Potosi (Russell and Lamm 1978; A. Garza de Leon, The 
Bird Galley, in litt., 1990; L. Stenzel, Point Reyes Bird Observatory, 
in litt., 1992; R. Estelle, pers. comm., 1998). Currently, the majority 
of mountain plovers appear to winter in California, with fewer reported 
from Texas, Arizona, and Mexico.
    The only published scientific study of mountain plovers on their 
wintering habitat documented movement patterns, habitat preferences, 
and winter survival rates in the San Joaquin Valley and

[[Page 7591]]

Carrizo Plain Natural Area of California (Knopf and Rupert 1995). Due 
to the lack of published information on wintering birds, we examined 
Christmas Bird Count data, notes of California sightings compiled from 
American Birds, National Wildlife Refuge records, BLM surveys, and 
other information (J. Lowe, Cornell Laboratory of Ornithology, in 
litt., 1989; B. Deuel, in litt., 1992).


    In California, mountain plovers are most frequently reported and 
found in the greatest numbers in two general locations--(1) in the 
Central Valley south of Sacramento and west of U.S. Highway 99, and (2) 
the Imperial Valley in southern California. Throughout these areas, 
sightings occur on agricultural fields and noncultivated sites; 
noncultivated sites are preferred habitat (Knopf and Rupert 1995). 
Within the Central Valley, flocks of up to 1,100 birds have been seen 
recently in Tulare County (Knopf and Rupert 1995). The Carrizo Plain 
Natural Area in San Luis Obispo County also is recognized as an 
important wintering site, with wintering birds reliably reported from 
the west side of the Carrizo Plain Natural Area since 1971 (S. Fitton, 
in litt., 1992). The Sacramento Valley portion of the Central Valley 
also provides wintering habitat for flocks of mountain plovers within 
Solano and Yolo Counties. During the 1998 census, 230 and 187 mountain 
plovers were observed within each of these counties, respectively (K. 
Hunting, California Department of Fish and Game, in litt., 1998).
    About 2,000 mountain plovers were counted on agricultural fields in 
the Imperial Valley in 1994 (B. Barnes, National Audubon Society, in 
litt.. 1994). At other locations in southern California, birds have 
been seen at Harper Dry Lake, Antelope Valley, San Jacinto Lake 
Wildlife Area, and the Tijuana River Valley (K. Garrett, no 
affiliation, pers. comm., 1989; G. Cardiff, no affiliation, pers. 
comm., 1992; T. Paulek, California Department of Fish and Game, pers. 
comm., 1992; E. Copper, unaffiliated, in litt., 1992). Mountain plovers 
are considered extirpated (extinct) from Orange County (B. Harper, U.S. 
Fish and Wildlife Service, in litt., 1990).

Arizona, Texas, Nevada and Mexico

    Wintering mountain plovers also are reported from other areas, but 
in much lower numbers than are reported from California. From 1983 to 
1991, a total of 30 to 180 mountain plovers were reported from 
southeastern Arizona (J. Witzeman, Audubon Society, pers. comm., 1992). 
In Texas, up to 130 mountain plovers were reported from Guadalupe, San 
Patricio, and Williamson Counties (G. Lasley, Regional Editor American 
Birds, pers. comm., 1992). Mountain plovers also have been sighted 
throughout the year in Texas in Val Verde, Nueces, Kleburg, Aransas, 
Tom Green, Concho, and Schleicher Counties (P. Horner, in litt., 1997), 
and at Laguna Atascosa National Wildlife Refuge (L. Laack, U.S. Fish 
and Wildlife Service, in litt., 1992). In Nevada, several mountain 
plovers were collected in the Lahontan Valley in 1940, with a few 
observed there in the 1990's (Alcorn 1946; F. Knopf, pers. comm., 
1995). In January 1992, 148 mountain plovers were counted at the north 
end of Laguna Figueroa, Baja California, Mexico (L. Stenzel, in litt. 
1992). About 150 mountain plovers were seen on a prairie dog town in 
San Luis Potosi, Mexico, in January 1998 (R. Estelle, pers. comm., 

Total Mountain Plover Population Abundance and Trend Estimates

    Historically, breeding mountain plovers were reported as locally 
rare to abundant, and widely distributed in the Great Plains region 
from Canada south to Texas (Coues 1878, Knight 1902, McCafferty 1930, 
Bailey and Neidrach 1965). On wintering grounds in California, as many 
as 10,000 mountain plovers were repeatedly counted in the San Joaquin 
Valley during the 1960's (J. Engler, U.S. Fish and Wildlife Service, in 
litt., 1992). In January 1994, 3,346 mountain plovers were counted 
during a simultaneous survey of 17 sites throughout California (B. 
Barnes, in litt., 1994). A similar coordinated survey in California in 
January 1998 counted 2,179 (Hunting, in litt., 1998).
    We present the above estimates of mountain plover relative density 
and abundance rangewide and within each state to give the reader an 
indication of the variability in information reported in published 
literature and other references. The estimates of abundance provided 
for each State or area are usually from different researchers, from 
different times, and using different techniques. Therefore, the 
estimates should not be considered comparable to one another, nor 
necessarily additive. Knopf (1996b) estimated the total 1995 North 
American population to be between 8,000 and 10,000 birds. He arrived at 
this estimate beginning with a one day winter count of 3,346 mountain 
plovers at all known historical sites in California, assuming that at 
least one-half of all mountain plovers in California were missed by 
that count, and adding an estimated 1,000--3,000 birds that winter in 
Texas and Mexico.
    Knopf (1994) reported that between 1966 and 1991, continental 
populations of the mountain plover declined an estimated 63 percent. 
Breeding Bird Survey trend analysis completed for the period 1966 
through 1996 yields an estimated annual rate of decline of 2.7 percent 
(P = 0.02, 95 percent confidence intervals -4.7, -0.6; Sauer et al. 
1997). Knopf and Rupert (in press) hypothesized that reduced 
productivity as a result of tillage on cultivated lands used for 
nesting may explain the annual rate of decline of this species. The 
mountain plover's decline is considered a major conservation concern 
(Knopf 1994, 1996b).

Previous Federal Action

    On December 30, 1982, we designated the mountain plover as a 
category 2 candidate species, meaning that more information was 
necessary to determine whether the species status is declining, stable, 
or improving (47 FR 58458). In 1990, we prepared a status report on the 
mountain plover suggesting that Federal listing may have been warranted 
(Leachman and Osmundson 1990). We elevated the mountain plover to a 
category 1 candidate species in the November 15, 1994 Animal Candidate 
Notice of Review (59 FR 58982). At that time, category 1 candidate 
species were defined as those species for which we had sufficient 
information on biological vulnerability and threats to support issuance 
of a proposed rule to list. In 1996, we redefined candidate species and 
eliminated category 2 and 3 candidate designations (61 FR 64481). 
Candidate species were defined using the old category 1 definition. The 
mountain plover retained its candidate species designation as reported 
in the September 19, 1997, Review of Plant and Animal Taxa (62 FR 
49398). On July 7, 1997, we received a petition to list the mountain 
plover as threatened from Jasper Carlton of the Biodiversity Legal 
Foundation. The Service responded by notifying the petitioners that 
petitions for candidate species are considered second petitions, 
because candidate species are species for which we have already decided 
that listing may be warranted. Therefore, no 90-day finding was 
required for Biodiversity Legal Foundation's petition.

Summary of Factors Affecting the Species

    Section 4 of the Endangered Species Act (Act) of 1973, as amended 
(16 U.S.C. 1531 et seq.) and regulations (50 CFR part 424) promulgated 
to implement the listing provisions of the

[[Page 7592]]

Act set forth the procedures for adding species to the Federal lists. A 
species may be determined to be endangered or threatened due to one or 
more of the five factors described in section 4(a)(1). These factors 
and their application to the mountain plover (Charadrius montanus) are 
as follows:

A. The Present or Threatened Destruction, Modification, or Curtailment 
of its Habitat or Range.

    As discussed below, mountain plover habitat is threatened by the 
conversion of grasslands to croplands and urban uses, domestic 
livestock management, and other land uses (e.g., prairie dog control, 
mineral development) throughout mountain plover breeding and wintering 
Historical Conversion of Grassland in Breeding Range
    Conversion of grassland to cropland within the breeding range of 
the mountain plover has been extensive, with about 32 percent of the 
grasslands in the Great Plains now converted (Laycock 1987, Knopf and 
Rupert in press). Approximately 20 percent of Wyoming's and 80 percent 
of Texas' shortgrass prairie has been lost (comparable data not 
available for each State, Samson and Knopf 1994, Knopf and Samson 
1997). The demand for agricultural development at the turn of century 
stimulated grassland conversion to croplands at both breeding and 
wintering locales. Conversions continued in later years to meet demands 
during World Wars I and II. In the 1940s, some additional land was 
plowed to take advantage of favorable precipitation and high wheat 
prices after World War II (Laycock 1987). Under the Soil Bank Act of 
1956, participating farms withdrew cropland from production for 3-10 
years. At the peak of the program in 1961, 14.1 million acres (ac) in 
the Great Plains were planted to grasses. Laycock (1987) suggests that 
observations show that almost all of this area was plowed again 
beginning in the early 1970s, along with previously unbroken grassland. 
Thus, the Soil Bank Program of 1956 was successful as a wildlife 
habitat conservation measure only in the short term. Later, during the 
Russian wheat sale of 1972 and authorization and implementation of 
Federal water projects in California's Central Valley, conversions of 
grassland continued (see Moore et al. 1990, Williams 1992). During the 
1970s and 1980s, an estimated 572,000 ac (228,800 ha) and 15,000 ac 
(6,000 ha) of previously unbroken grassland were plowed in Colorado and 
Kansas (Laycock 1987). Simultaneously, domestic livestock replaced 
native ungulates as the primary grazer at both breeding and wintering 
locations, and livestock management practices that encouraged 
vegetative uniformity were adopted (see Knopf 1996c, and Knopf and 
Rupert in press).
Current Conversion of Grassland in Breeding Range
    We investigated recent loss of native rangeland within the breeding 
range of the mountain plover using the National Resources Inventory 
(NRI) of the U. S. Department of Agriculture Natural Resources 
Conservation Service (NRCS). The NRI is a comprehensive database of 
natural resource information on non-federal lands of the United States 
that focuses on soil, water, and related resources. Although the survey 
is now repeated every five years, the earliest NRI data is available 
from 1982 (U.S. Department of Agriculture Soil Conservation Service 
1994). The 1992 NRI Summary Report provided estimates of change in 
rangeland acreage, 1982-1992, for each state. Rangeland was defined as 
a land cover/use category that includes land on which the climax or 
potential plant cover is composed principally of native grasses, grass-
like plants, forbs, or shrubs suitable for grazing, and introduced 
forage species that are managed like rangeland. We believe that this 
cover type would most likely represent the vegetative elements required 
by breeding mountain plovers.
    Colorado, Montana, and Wyoming are the three States with the 
majority of breeding mountain plovers; some breed in Kansas, Nebraska, 
and Oklahoma. Using areas inventoried by Knowles and Knowles (1998) and 
Shackford and Leslie (1995b), we compared the change in rangeland that 
has occurred in their inventory areas between 1982 and 1992. With the 
exception of Phillips and Blaine counties, Knowles and Knowles (1998) 
report more mountain plovers from Broadwater, Golden Valley, Jefferson, 
Madison, Valley, and wheatland counties than other locations in 
Montana. The counties inventoried by Shackford and Leslie (1995b) 
closely describe the area commonly reported as the mountain plover 
breeding range in Colorado, Kansas, Nebraska, Oklahoma, and Wyoming. We 
believe the 30 counties in the six states which we selected for review 
of NRI data are a good representation of areas either currently or 
historically occupied by mountain plovers.
    Data were not available for all of the selected Montana counties. 
From 1982 to 1992, the amount of rangeland in the selected counties of 
Wyoming decreased 25,300 ac, in Colorado 466,200 ac, in Nebraska, 
18,400 ac, in Kansas, 30,700 ac, and in Oklahoma 33,000 acres. These 
decreases occurred because of conversion to a variety of landuses, 
including cropland, developed land, and other rural lands (U. S. 
Department of Agriculture Soil Conservation Service 1994). These data 
suggest that the conversion of grasslands remains a significant threat 
to the species. Given the fact that mountain plovers are endemic to 
grasslands, we believe that a similar proportion of mountain plover 
habitat was likely lost during that time period. In fact, the 
conversion of grasslands to cropland is reported by many authors as a 
cause for the decline of mountain plovers and their habitat (e.g., 
Graul and Webster 1976, Fauna West 1991, Knopf and Rupert in press).
    Mountain plovers are known to breed on private grasslands near the 
Little Belt and Big Snowy mountains in Montana, on private lands within 
the boundary of the Pawnee National Grassland in Colorado, and in other 
areas that could be converted to croplands (Knowles and Knowles 1993, 
Knopf and Rupert in press). Three mountain plover nest sites on 
grasslands in central Montana were converted to cropland in 1995 under 
a farm plan approved by the Natural Resources Conservation Service, and 
grassland conversion is occurring at other locations in Montana 
(Knowles and Knowles 1996, 1998).
Cultivated Areas in Breeding Range as Potential Population Sinks
    A direct loss of habitat is not the only effect of grassland 
conversion in the breeding range. Conversion may not only destroy 
existing mountain plover breeding sites (see Knowles and Knowles 1996b, 
1998) and eliminate the opportunity to manage grasslands to provide 
future nesting sites (e.g., through burning and grazing), it also may 
create habitats that attract breeding mountain plovers which would then 
be exposed to the tilling of cultivated fields to control weeds. This 
tilling can destroy mountain plover nests, eggs, and chicks (Shackford 
and Leslie 1995a,b; Knopf 1996b; Knopf and Rupert in press).
    In the last 25 years, Great Plains' farms have become larger and 
new crops have become economically feasible. Many farmers now plant 
extensive areas to sunflowers and millet, as well as winter and spring 
wheat. Fields may remain fallow until early May, after most mountain 
plovers have started nesting. Many nests are then destroyed by farm 
equipment when the fields are planted in May. Mountain plovers may 
renest on these fields, but then likely

[[Page 7593]]

abandon nests as the grain crop becomes too tall to allow plovers to 
scan their surroundings for predators (Knopf 1996b). In other 
instances, fallow fields may not be planted, but may be tilled 
periodically to control weeds.
    During the nesting season of 1995, Shackford and Leslie (1995b) 
searched 999 km around cultivated fields in 68 counties of eight 
States. They observed 54 mountain plovers on a total of 29 cultivated 
fields in 13 counties in five of the eight States: Colorado, Montana, 
Nebraska, Oklahoma, and Wyoming. The majority of plovers observed on 
cultivated fields were in the southern portion of the range (53 of 54 
birds): Laramie County, Wyoming (19 birds), southwestern Nebraska (13), 
and eastern Colorado (17). Shackford and Leslie (1995b) concluded that 
fewer birds are found nesting in cultivated fields in northern 
latitudes because upland crops are sparse in Montana and Wyoming, there 
is a shorter growing season, and spring wheat planted in northern 
latitudes is disturbed more frequently than the winter wheat planted in 
the south. The short intervals between disturbances for spring wheat 
would not normally allow enough time for breeding, nesting, and young 
    In 1993 and 1994, 48 percent of nests located on cultivated fields 
in Colorado, Oklahoma, and Kansas were destroyed by tilling (Shackford 
and Leslie 1995a). Although the long-term effect of tilling on mountain 
plover productivity and abundance is not known, cultivated lands may 
represent a reproductive ``sink'' (Knopf 1996b; Knopf and Rupert in 
press). Pulliam (1988) described a reproductive sink as habitat where 
reproduction of a species is less than mortality, so that immigration 
from more productive habitats (i.e., ``sources'') is needed to maintain 
the species' presence at the sink. Sinks are habitats where breeding 
efforts are misrepresented as recruitment into the population, but 
where the mortality actually causes a population decline. We concur 
with Knopf and Rupert (in press) that the source-sink dynamics (as 
described by Pulliam (1988)) are likely operating on the grassland-
cultivated sites used by mountain plovers in Colorado, Kansas, and 
    Many grasslands are not suitable breeding habitat, and therefore, 
are not used by mountain plovers. However, conversion of these 
grasslands also can be considered detrimental because such conversion 
may create locally acceptable habitat (Knopf and Rupert in press) on 
which mountain plovers are then exposed to tilling (i.e., creation of 
sink habitat, see above). Consequently, grassland conversion may be 
considered a threat to mountain plover conservation whether or not the 
grasslands are presently suitable breeding habitat, particularly when 
conversions are proposed within the southern portion of the bird's 
breeding range.
    Grasslands in the breeding range also are being converted to urban 
uses. Nationwide, between 1982 and 1992, a 14 million ac (5,600,000 ha) 
increase in developed land came in part from conversion of 2 million ac 
of rangeland (U.S. Department of Agriculture Soil Conservation Service 
1994). In Park County, Colorado, which may support about 1,000 mountain 
plovers, the number of residential building permits has tripled between 
1991 and 1997 in areas of the County known to have breeding habitat 
(Hanson 1997; G. Nichols, Park County, Colorado, in litt. 1998).
Historical Conversion of Grassland in Winter Range
    In the early 1900s, a great number of mountain plovers were 
reported on wintering areas in California on both grasslands and 
agricultural lands (Grinell et al. 1918). Prior to extensive human 
development, grasslands occupied about 8,900,000 hectares (ha) (22 
million ac) throughout California, with about 20 percent occurring in 
the San Joaquin Valley (Dasmann 1965 and Burcham 1982 cited in Moore et 
al. 1990. During agricultural development, extensive conversion of 
natural habitats occurred and proportionately more grasslands were 
converted than any other cover type (Ewing et al. 1988, Moore et al. 
1990). The amount and variety of mountain plover habitat has been 
significantly reduced throughout the Central Valley and in southern 
California. To more fully evaluate the degree of mountain plover 
habitat conversion that has occurred, we reviewed the habitat 
inventories completed for other declining terrestrial species in the 
San Joaquin Valley. While the San Joaquin Valley encompasses only the 
southern portion of the Central Valley, we believe the trend there is 
representative of wintering habitat degradation elsewhere.
    Grasslands in the San Joaquin Valley have been nearly extirpated, 
with less than 60,700 ha (150,000 ac) in the San Joaquin Valley floor 
remaining unaffected by cultivation or urbanization (Service 1997). 
Consequently, habitats preferred by mountain plovers have been reduced 
to less than 4 percent of their historical abundance (Knopf and Rupert 
1995, Anderson et al. 1991). Research in the San Joaquin Valley 
documents that wintering mountain plovers prefer Valley sink scrub and 
grasslands over any of the more common cultivated land (Anderson et al. 
1991; Knopf and Rupert 1995). However, the sink scrub and grasslands 
occupy no more than about 26,400 ha (66,000 ac) of the San Joaquin 
Valley (Anderson et al. 1991). Mountain plovers in the San Joaquin 
Valley are dependent on these core areas of uncultivated lands for 
early winter survival, and further loss of these areas would be 
detrimental to the species (Knopf and Rupert 1995). Apparently due to 
the scarcity of uncultivated wintering habitat, mountain plovers use 
croplands created by annual cultivation as alternate foraging areas 
(Knopf and Rupert 1995). Such use may give the appearance that 
conversion to cropland is benign. However, mountain plovers may not 
benefit in the long term because the cultivated lands are commonly 
treated with pesticides and may become urbanized (American Farmland 
Trust 1989, Moore et al. 1990, Knopf 1996b). Most of the remaining 
undeveloped lands in the San Joaquin Valley are primarily in the 
foothills of the Valley, and are lands that have less potential for 
agricultural production (Moore et al. 1990, Service 1997). While the 
Carrizo Plain Natural Area contiguous to the west side of the Valley is 
recognized as a regular wintering area, only about 10 percent of its 
102,792 ha (254,000 ac) has vegetation and topography suitable for 
mountain plovers (U.S. BLM 1995, S. Fitton, in litt., 1992).
Effects of Range Management on Mountain Plover Habitat
    Historically, mountain plover habitat at both breeding and 
wintering sites was a byproduct of the nomadic behavior of bison, elk, 
and pronghorn, and the fossorial (digging) behavior of numerous 
rodents. Today prairie dogs and kangaroo rat numbers have been reduced 
on a significant portion of their former range, and the grazing effects 
of the dominant herbivore (domestic livestock) are usually closely 
managed by rotating the livestock within fenced pasture allotments. 
Current range management practices for domestic livestock, together 
with extensive eradication of prairie dogs and other burrowing rodents, 
has adversely affected mountain plover habitat, as detailed below.
    Some current domestic livestock grazing management emphasizes a 
uniform grass cover to minimize grassland and soil disturbance (Knopf 
and Rupert in press), whereas the landscape created by the native 
herbivores was a mosaic of grasses, forbs, and bare ground that could

[[Page 7594]]

change frequently in time and location. The shift to livestock grazing 
strategies that favor uniform cover is believed to be partly 
responsible for the decline of mountain plovers in Oklahoma and Canada 
(Flowers 1985, Wershler 1989). Mountain plovers are no longer reported 
from the Lewis Ranch in central Montana since elimination of grazing 
there in 1993 (Knowles and Knowles 1998). Mountain plovers on the 
Pawnee National Grassland are closely associated with heavily-grazed 
sites. Therefore, in order to prevent deterioration of existing 
mountain plover breeding habitat, the Forest Service has deferred 
implementation of new grazing management plans that would have reduced 
stocking rates (Forest Service 1994b). However, similar attention to 
the vegetative requirements of mountain plovers is not in place 
throughout their breeding range. The decline in the cattle and sheep 
industry has caused additional rangeland to be converted to cropland, 
which is believed to have eliminated some of the mountain plover 
habitat in Montana (Fauna west 1991, Knowles and Knowles 1998).
    Range management projects to improve forage conditions for domestic 
livestock are conducted on public and private lands throughout the 
range of the mountain plover. Examples of these projects include 
``pitting'' to increase moisture retention in the soil, introduction of 
exotic grass species such as crested wheatgrass, watershed improvement 
projects, and fire suppression (Graul 1980, Fauna west 1991, Knowles 
and Knowles 1993). These activities enhance the development of taller 
vegetation and have eliminated suitable mountain plover nesting 
habitats in Montana and Colorado (Graul and Webster 1976, Knowles and 
Knowles 1993).
Effects of the Decline of Burrowing Mammals on Mountain Plover Habitat
    The decline of the mountain plover is partially due to the decline 
of prairie dogs in plover breeding range and the decline of small 
burrowing mammals in plover winter range (Knowles et al. 1982; Fitton, 
in litt., 1992, Knopf 1994).
Breeding Range
    Mountain plovers occur within prairie dog towns in Colorado, 
Montana, Wyoming, and Oklahoma (Knowles et al. 1982; Flowers 1985; 
Shackford 1991; Godbey 1992; Nelson 1993; Edwards, in litt., 1994; T. 
Byer, in litt., 1997; S. Dinsmore, pers. comm., 1998). Active prairie 
dog towns in Montana have shorter vegetation and more abundant mountain 
plover food, and therefore are better foraging sites than adjacent 
sites without prairie dogs (Olson 1985). In Phillips County, Montana, 
mountain plovers were found to selectively use only those active 
prairie dog towns that also were grazed by cattle; mountain plovers 
were not seen on inactive or ungrazed prairie dog towns (Knowles et al. 
1982). Most of the mountain plover nests found on survey transects in 
Phillips County during the past 6 years were located on prairie dog 
towns (S. Dinsmore, pers. comm., 1998). The largest population of 
mountain plovers in Montana occurs on prairie dog colonies, and between 
1992 and 1996, prairie dog occupation of these colonies was reduced by 
as much as 80 percent as a result of sylvatic plague (J. Grensten, 
pers. comm., 1998). Mountain plover numbers along prairie dog transect 
routes within the area affected by plague declined from 80 in 1991 to 
19 in 1997, but increased to 27 in 1998 following some recovery of the 
prairie dog population (S. Dinsmore pers. comm. 1998). We believe that 
the best information available indicates that mountain plovers in 
Phillips County are dependent on the activities of prairie dogs. 
Because mountain plovers breeding in Montana represent a significant 
part of the species total population, eradication of prairie dogs in 
Montana would not only be detrimental to local conservation of plovers 
(Knowles and Knowles 1998), but also could impact their viability 
    In Wyoming, prairie dogs on the Thunder Basin National Grassland 
effectively maintain the vegetative characteristics required by 
mountain plovers. To maintain these characteristics in the absence of 
prairie dogs, more intensive grazing by domestic livestock or native 
ungulates, or burning, would have to be conducted (T. Byer, pers. 
comm., 1998). The importance of prairie dogs to mountain plover habitat 
on the Pawnee National Grassland in Colorado was recently recognized 
following a significant reduction in habitat caused by record rainfall 
there in 1995. Prairie dogs on the Grassland have been effective in 
maintaining the vegetative structure suitable for nesting mountain 
plovers, while the vegetation at similar sites without prairie dogs is 
now too tall or dense to be suitable habitat for mountain plovers.
    Prairie dog abundance and distribution has been reduced by up to 98 
percent across the species range due to concerted efforts aimed at 
eradication of prairie dogs, extensive habitat reduction and 
fragmentation, and sylvatic plague (Marsh 1984, Whicker and Detling 
1993, Miller et al. 1994, W. Gill, Service, in litt. 1995).
    Prairie dog control continues to occur on private and public lands 
throughout the mountain plover's breeding range. Prairie dog 
conservation efforts now being implemented at black-footed ferret 
recovery sites in southeastern Wyoming (56 FR 41473) and north-central 
Montana (59 FR 42696) will prevent prairie dog control from threatening 
the success of the ferret recovery efforts. Mountain plovers at these 
sites will be incidentally protected by these efforts, but similar 
strategies are not in place throughout the species range. Outbreaks of 
sylvatic plague continue to occur, and no measures are available to 
effectively prevent or minimize the negative effect of plague on 
prairie dog populations.
    Prairie dog towns also are threatened by land use conversion 
(Knowles and Knowles 1993). Further loss of prairie dog towns within 
the current breeding range of the mountain plover would be detrimental 
to plover conservation. Conversely, the conservation of the mountain 
plover can be enhanced by implementing strategies to increase the 
distribution and abundance of prairie dogs on breeding habitat.
Wintering Range
    Some wintering habitat in California continues to be maintained in 
suitable conditions by the activities of giant kangaroo rats and 
California ground squirrels (Knopf and Rupert 1995). We estimate that 
the federally listed giant kangaroo rat occupies less than about 2 
percent of its former range due primarily to conversion of grassland 
habitat to agriculture and urbanization, and secondarily to other 
incidental human activities and control of California ground squirrels 
(52 FR 283). Further loss of giant kangaroo rat colonies within the 
current winter range would be detrimental to plover conservation. 
Conversely, the conservation of the mountain plover can be enhanced by 
implementing strategies to increase the distribution and abundance of 
giant kangaroo rats on wintering habitats.
Oil, Gas, and Mineral Development in Mountain Plover Breeding Habitat
    Oil and gas leasing and development commonly occur throughout the 
breeding range of the mountain plover. Ongoing development of natural 
gas resources in southwest Wyoming now exceeds the rate of development 
projected 3 years ago, and the volume of natural gas suspected to occur 
could make the rate of development the highest in the Nation (R. 
Amidon, BLM, pers. comm., 1998). Oil and gas

[[Page 7595]]

development requires construction of individual well pads, access 
roads, travel corridors, and pipelines (Brockway 1992). Roads present a 
direct hazard for a variety of reasons. Mountain plovers nest on nearly 
level ground (often near roads), adults and chicks often feed on or 
near roads, and roads may be used as travel corridors by mountain 
plovers, all of which make plovers susceptible to being killed by 
vehicles (McCafferty 1930, Laun 1957, Godbey 1992, Knowles and Knowles 
1996). Chicks and adults are vulnerable to stress caused by human 
disturbance, and chicks require shading by adults to avoid heat (Graul 
1975). Because adults may abandon chicks during distraction displays 
(Graul 1975), any human activity that elicits distraction displays is 
likely to increase the vulnerability of chicks to stress. Thus, 
development of oil and gas resources could adversely affect mountain 
plover habitat or cause the death of individuals (Brockway 1992).
    Mineral resources found within the range of the mountain plover 
include coal, uranium-vanadium, bentonite, and hard rock minerals. Many 
of these resources occur on public lands and are commonly mined using 
surface mining techniques. Up to 25 percent of the mountain plover 
habitat at the Antelope Coal Mine in Converse County, Wyoming, has been 
affected by mining disturbance in the past (K. Edwards, in litt., 
1994), but mountain plover sightings at the coal mine have remained 
fairly stable in recent years, and the habitat impacts may not have 
affected population levels (B. Postovit, Powder River Eagle Surveys, 
pers. comm., 1998). However, other surface coal mining is proposed in 
Wyoming that may impact mountain plovers or their habitat (M. Jennings, 
U.S. Fish and Wildlife Service, in litt., 1998).

B. Overutilization for Commercial, Recreational, Scientific Educational 

    Prior to the passage of the Migratory Bird Treaty Act in 1916, 
mountain plovers were commercially hunted for food. There is no recent 
evidence that mountain plovers are overutilized for any purpose.

C. Disease or Predation

    Disease-related factors are not known to be a problem to the 
species. Mountain plovers are most vulnerable to terrestrial and avian 
predators as eggs and chicks, and are only rarely killed as adults. 
Potential avian and terrestrial predators include the prairie falcon 
(Falco mexicanus), loggerhead shrike (Lanjus ludovicianus), swift fox 
(Vulpes velox), ground squirrels (Spermophilus sp.), and coyote (Canis 
latrans) (Graul 1975). Nest predation at the Pawnee National Grassland 
has ranged between 15 to 74 percent from 1969 to 1994 (Graul 1975, 
Miller and Knopf 1993, Knopf and Rupert 1996). A high rate of nest 
predation by swift fox at the Pawnee National Grassland in 1993 and 
1994 may have been due to temporarily reduced prey resources, and is 
not believed to be a factor in the long-term decline of the mountain 
plover population (Knopf and Rupert 1996).

D. The Inadequacy of Existing Regulatory Mechanisms

    Protecting the mountain plover and its habitat is complicated 
because its breeding and wintering habitats occur over a wide 
geographic area, which includes private and public land, and numerous 
State and Federal authorities. Federal laws that provide protection of 
mountain plovers include the Federal Land Policy and Management Act, 
Federal Onshore Oil and Gas Leasing Reform Act, Endangered Species Act, 
Fish and Wildlife Coordination Act, Federal Agriculture Improvement and 
Reform Act of 1996, and Migratory Bird Treaty Act. To various degrees, 
these laws address Federal candidate species, migratory birds, or 
declining species when evaluating potential effects of federally 
authorized, funded, or permitted actions. Further, some Federal 
agencies have adopted policies requiring consideration of declining 
species during project review, to ensure that Federal actions do not 
cause a trend toward Federal listing. However, the effectiveness of 
these existing Federal regulations and policies are highly variable and 
may not be sufficient to reverse the species' decline throughout its 
    The Forest Service has adopted an interim mountain plover 
management strategy for oil and gas activities on the Pawnee National 
Grassland because of the potential impact these activities would have 
on the species (U.S. Forest Service 1994). The BLM has adopted the same 
strategy for oil and gas activities under its administration at the 
same location (U.S. BLM 1994). Spatial buffers to protect mountain 
plovers have also been adopted on Forest Service and Bureau lands in 
Colorado, Wyoming, and Utah (M. Ball, Forest Service, in litt., 1997; 
T. Byer, in litt., 1997; T. Dabbs, in litt., 1997). However, many of 
the mineral resources occur as split estate ownership, where the 
surface is owned by the Federal government but the subsurface minerals 
are owned by private parties. Strategies adopted by Federal agencies to 
protect mountain plovers are not as effective on split estate lands 
because the Federal Government has less regulatory authority over 
private surface activities. In southwest Wyoming the ``checkerboard'' 
pattern of alternating private and public land (Federal and State 
sections) also reduces the effectiveness of Federal plover conservation 
    Land exchange or disposal by Federal agencies may also involve 
mountain plover habitat. For example, land exchanges on the Thunder 
Basin National Grassland in Wyoming have resulted in transfer of known 
nesting habitat to private ownership, as well as transfer of nesting 
habitat on private land to Forest Service ownership (T. Byer, pers. 
comm., 1998). In Colorado, the BLM has identified numerous parcels of 
public land that are available for exchange or disposal to the public, 
including parcels in Park County known to be mountain plover habitat 
(L. Deike, BLM, in litt., 1997). Disposal of these lands requires 
review by the BLM, yet the candidate status of the mountain plover may 
not be effective as a mechanism to retain all breeding sites in public 
ownership (E. Brekke,BLM, pers. comm., 1998). While federal ownership 
of mountain plover habitat is not necessary to insure conservation, 
retaining known habitat in federal ownership reduces the burden of 
conservation on private landowners.
    The mountain plover is now classified as endangered in Canada, 
threatened in Nebraska, a ``species of special interest or concern'' in 
Montana, Oklahoma, and California, and designated a ``species in need 
of conservation'' in Kansas (Wershler and Wallis 1986; Flath 1984; E. 
Hunt, California Department of Fish and Game, in litt., 1990; Nebraska 
Game and Parks Commission 1992; Oklahoma Department of Wildlife 
Conservation 1992; Kansas Department of Wildlife and Parks 1992). The 
mountain plover is currently believed to be extirpated from North 

Dakota and South Dakota (Faanes and Stewart 1982). Only California and 
Nebraska have laws requiring evaluation of State-listed species through 
a consultation process. States other than those identified above have 
not given the mountain plover any special designation. In 1995, 
Colorado, Kansas, Montana, Nebraska, New Mexico, Oklahoma, and Wyoming, 
designated the mountain plover as a ``species of management concern'' 
under the Partners in Flight Program (Service, in litt., 1995). It is 
not known if the bird has any official designation in Mexico.
    State listing can encourage State agencies to use existing 
authorities to achieve recovery, stimulate research,

[[Page 7596]]

and allow redirection of priorities within State natural resource 
departments. However, without measures to protect the species' habitat, 
such State laws are generally inadequate to ensure conservation of the 

E. Other Natural or Manmade Factors Affecting its Continued Existence

Natural Factors Affecting Nesting
    Mountain plover nests are often found grouped in localized areas, 
which suggests a loose colonialism during the breeding season (Graul 
1975). Results of studies conducted in Colorado and Montana suggest a 
high degree of site fidelity in mountain plovers, with both males and 
females returning to nest within several hundred meters of the previous 
year's nest site, and banded chicks returning as adults the following 
year to nest at their natal areas (Graul 1973, Knopf 1996b).
    The mountain plover's narrow range of habitat requirements combined 
with its site fidelity increases its vulnerability to impacts at 
traditional breeding locales. Although mountain plovers or their 
habitat may be affected by localized climatic events (Graul 1973, 
1975), we do not believe such events have contributed to the historic 
decline of the species. However, a declining mountain plover population 
combined with high site fidelity characteristics may increase their 
vulnerability to such events in the future. For example, the Pawnee 
National Grassland received 30 cm (12 in) of rainfall in one month 
during the spring of 1995 (Ball, in litt. 1997) which caused vegetation 
growth in 1995 that averaged 30 cm (12 in) in height, thereby 
eliminating mountain plover nest site characteristics. Independent 
surveys determined that mountain plover abundance on the Pawnee 
National Grassland has declined by as much as 90 percent compared to 
the pre-1995 surveys (Ball, in litt., 1997; F. Knopf, in litt., 1997). 
In 1998, mountain plovers were not observed at their traditional 
nesting sites on the Pawnee National Grassland, suggesting that the 
deteriorated habitat conditions have caused mountain plovers to abandon 
much of this area (F. Knopf, in litt., 1998). Similarly, researchers 
witnessed the destruction of all nests and chicks in a given area 
during a single flash flood event in 1997 in central Montana (C. 
Knowles, pers. comm., 1998). Therefore, climatic events that render 
areas unsuitable for nesting may mean that birds who return to that 
area for nesting must expend additional time and energy locating a 
suitable alternative area. This search may result in a decreased 
reproductive success for that year. The long-term effect of such 
naturally occurring catastrophes on mountain plover viability is not 
known, but populations at low abundance are more vulnerable to 
extirpation by such events. Naturally occurring events can increase the 
risk of extirpation at local breeding sites.
Manmade Factors Affecting Nesting
    In addition to loss of habitat, human disturbance during the 
nesting period may directly impact mountain plovers due to their 
sensitivity to stress (Wershler and Wallis 1986). Mountain plover 
chicks less than 2 weeks old may die in 15 minutes if shade is not 
available on days when the temperature exceeds 27 deg. C (81 deg. F) 
(Graul 1975). Adults have been known to abandon eggs after being 
disturbed on the nest, and adults also may die from stress (Graul 
1975). Consequently, any human activity that significantly modifies 
behavior by adults will not only increase the exposure of chicks to 
natural elements, but also will increase the vulnerability of adults to 
stress-related mortality.
    Grasshoppers that occur throughout the breeding range of the 
mountain plover can reach population levels considered a threat to 
agriculture, and stimulate grasshopper control measures. Although 
cooperative grasshopper control programs between the Animal and Plant 
Health Inspection Service (APHIS) and private land owners have been 
abandoned, federally-subsidized control can be implemented if a severe 
grasshopper outbreak occurs and congressional funding is provided (L. 
McEwen, Colorado State University, pers. comm., 1998). Grasshopper 
control methods can reduce the abundance of grasshoppers by more than 
90 percent, as well as reduce the abundance of nontarget insects (Fair 
et al. 1995). Although control is designed to reduce rather than 
eradicate grasshoppers, mountain plover productivity may be influenced 
by a reduction in prey abundance (Animal and Plant Health Inspection 
Service 1987, Graul 1973, Knopf 1996b, Knopf and Rupert 1996).
    In addition, mountain plovers are at risk from increased metabolism 
of DDE residues if their foraging behavior is altered to compensate for 
this reduced insect abundance (U.S. Environmental Protection Agency 
(EPA) 1975, Fair et al. 1995). Grasshopper control subsidized by APHIS 
is designed to minimize impacts to wildlife species; however, due to 
the reduction in Federal programs to control grasshopper infestations, 
private landowners may choose control methods that increase the 
contaminant risk to mountain plovers. Therefore, grasshopper control on 
breeding habitat is considered a potential threat to mountain plovers.
Manmade Factors--Wintering
    In California, pesticides are applied to cultivated fields during 
the 5 months that mountain plovers occupy these wintering habitats 
(Knopf 1996b). Birds are exposed to pesticides by adsorption through 
the skin, preening, ingestion, and inhalation (Driver et. al. 1991). To 
investigate the potential threat of pesticides to mountain plovers, 
adults were collected from wintering habitats and eggs were collected 
from breeding habitats (F. Knopf, in litt., 1991). The adults and eggs 
were analyzed for concentration of organochlorines (hydrocarbon 
pesticides), selenium, and heavy metals. Forty whole-body samples of 
adults from the San Joaquin Valley had residues of DDE (a principal 
environmental metabolite of DDT) ranging from near 1 to 10 parts per 
million ( L. Carlson, Service, in litt., 1992; A. Archuleta, Service, 
pers. comm.. 1995). Twenty-two of the 54 eggs collected in Colorado and 
Montana had DDE residues similar to those found in the wintering birds.
    Although these DDE residues in eggs do not appear detrimental to 
mountain plover reproduction, residues found in adults may cause death 
to some individuals if they are mobilized to the brain (U.S. 
Environmental Protection Agency 1975). While average selenium 
concentrations found in samples from winter habitats are below 
thresholds that would cause concern for population level effects, 
individual mountain plovers may be at risk in some locations (J. 
Skorupa, Service, pers. comm., 1993; A. Archuleta, pers. comm., 1995). 
Heavy metal concentrations were within acceptable thresholds (A. 
Archuleta, pers. comm., 1995).
    We have confirmed that the field application of 27 pesticides is 
responsible for killing numerous species of birds throughout the Nation 
(R. Smith, U.S. Fish and Wildlife Service, in litt., 1992). Diazinon, 
dimethoate, mevinphos, and chlorpyrifos are included on this list of 27 
pesticides, and are commonly applied to a variety of agricultural crops 
in Imperial County and the Central Valley of California from November 
through February (California Department of Pesticide Regulation, in 
litt., 1998). Ten other pesticides identified by the Service (R. Smith, 
in litt., 1992) as toxic to birds also are used in Imperial County and 
the Central Valley, but primarily during times when mountain plovers 
are absent. Studies conducted in the San

[[Page 7597]]

Joaquin Valley, California, to determine exposure of mountain plovers 
to organophosphates and carbamates were inconclusive. Cholinesterase 
activity levels of mountain plovers from the exposed site were 
consistently higher than those at the reference site, yet significant 
cholinesterase inhibition was not detected in any mountain plover (W. 
Iko, USGS-Biological Resources Division, in litt., 1997).


    In summary, threats to mountain plovers occur at both breeding and 
wintering locales. Conversion of rangeland to croplands has been 
significant on breeding habitat with about 30 percent of rangeland in 
the Great Plains now converted to crops. The cultivated lands now 
interspersed with prairie in the southern part of the plover's breeding 
range are hypothesized to represent a reproductive sink, which may 
significantly impact maintenance of a viable population. Similarly in 
the San Joaquin Valley, a significant wintering area, only 60,700 ha 
(150,000 ac) of the valley bottom remain currently uncultivated, and 
less than half of that may qualify as preferred habitat. Throughout the 
breeding range, bison are functionally extinct, prairie dogs have been 
considerably reduced, and current domestic livestock grazing management 
does not always promote the vegetative and bare ground structure 
required by mountain plovers. Similarly, the native herbivores that 
once maintained wintering habitats in California are either 
functionally or virtually extirpated. Oil and gas development occurs on 
core breeding sites on the Pawnee National Grassland, and is presently 
developing rapidly in southwest Wyoming. Rangeland grasshopper control 
may impact mountain plover productivity on breeding habitat, and 
mountain plovers are exposed to pesticide use while on wintering 
    We have carefully assessed the best scientific and commercial 
information available regarding the past, present, and future threats 
faced by the mountain plover in determining to issue this proposed 
rule. The present distribution and abundance of mountain plovers is at 
risk given the potential for these impacts to continue. Federal listing 
under authority of the Act is the only mechanism we can presently 
identify that ensures protection to the mountain plover throughout its 
life cycle and throughout its range, on both public and private lands. 
Therefore, based on this evaluation, the preferred action is to list 
the mountain plover (Charadrius montanus) as a threatened species. 
While not in immediate danger of extinction, we believe the mountain 
plover is likely to become an endangered species in the foreseeable 
future unless measures are taken to reverse the decline resulting from 
the above described threats.

Critical Habitat

    Critical habitat is defined in section 3(5)(a) of the Act as: (I) 
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 (I) essential to the conservation 
of the species and (II) that may require special management 
considerations or protection and; (ii) 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. The term ``conservation'' as defined in section 3(3) of 
the Act means ``to use and the use of all methods and procedures 
necessary to bring any endangered or threatened species to the point at 
which the measures provided pursuant to this Act are no longer 
necessary,'' i.e., the species is recovered and can be removed from the 
list of endangered and threatened species.
    Section 4(a)(3) of the Act, as amended, and implementing 
regulations (50 CFR 424.12) require that, to the maximum extent prudent 
and determinable, the Secretary designate critical habitat at the time 
the species is determined to be endangered or threatened. Our 
regulations (50 CFR 424.12(a)(1)) state that designation of critical 
habitat is not prudent when one or both of the following situations 
exist--(1) the species is threatened by taking or other human activity, 
and identification of critical habitat can be expected to increase the 
degree of threat to the species, or (2) such designation of critical 
habitat would not be beneficial to the species. We find that 
designation of critical habitat for the plover is not prudent because 
there would be no additional benefit to the species beyond that 
conferred by listing it as threatened. The reasons for this conclusion, 
including the factors considered in weighing the potential benefits 
against the risks of designation, are provided below.
    Potential benefits of critical habitat designation derive from 
section 7(a)(2) of the Act, which requires Federal agencies, in 
consultation with us, to ensure that their actions are not likely to 
jeopardize the continued existence of listed species or to result in 
the destruction or adverse modification of critical habitat of such 
species. Critical habitat, by definition, applies only to Federal 
agency actions. The 50 CFR 402.02 defines ``jeopardize the continued 
existence of'' as meaning to engage in an action that would reasonably 
be expected, directly or indirectly, to reduce appreciably the 
likelihood of both the survival and recovery of a listed species in the 
wild by reducing the reproduction, numbers, or distribution of that 
species. ``Destruction or adverse modification'' of critical habitat is 
defined as a direct or indirect alteration that appreciably diminishes 
the value of critical habitat for both the survival and recovery of a 
listed species. Such alterations include, but are not limited to, 
alterations adversely modifying any of those physical or biological 
features that were the basis for determining the habitat to be 
critical. Thus, in the section 7(a)(2) consultation process, the 
jeopardy analysis focuses on potential effects on the species' 
populations, whereas the destruction or adverse modification analysis 
focuses on the value of habitat to the species. However, both 
jeopardizing the continued existence of a species and adversely 
modifying critical habitat have similar standards and similar 
thresholds for violation of section 7 of the Act. Biological opinions 
that conclude that a Federal agency action is likely to adversely 
modify critical habitat but is not likely to jeopardize the continued 
existence of the species for which critical habitat has been designated 
are extremely rare historically; none have been issued in recent years.
    The mountain plover's distribution and biology are particularly 
relevant to the not prudent determination, as it relates to the section 
7 consultation process discussed above. The mountain plover is a 
neotropical migratory bird found in 11 different States in the western 
and southwestern United States and Mexico. It occupies grasslands or 
sites with grassland characteristics, including manmade landscapes such 
as sod farms and cultivated fields, and areas heavily grazed by cattle. 
Mountain plovers commonly occur on public lands at both breeding and 
wintering locales. The best-documented mountain plover breeding areas 
include lands managed by either the BLM or Forest Service in Montana 
and Colorado. Breeding and wintering mountain plovers occur on other 
Federal lands in each of these States, as well as in Wyoming, Utah, New 
Mexico, and California. The habitat in the other locations may be 
managed by the above agencies, or in a few cases by the

[[Page 7598]]

Service or the Department of Defense. In addition to their occurrence 
on Federal lands, mountain plovers also occur on private lands which 
may be enrolled in Federal programs that support commodity production. 
Federally sponsored activities on private land will receive the benefit 
of section 7 consultation, regardless of whether or not critical 
habitat is designated.
    As stated above, the mountain plover is a migratory bird that has a 
wide distribution throughout its breeding and winter range. While 
mountain plovers demonstrate a degree of fidelity to breeding 
locations, specific nest site locations can vary from year to year 
depending on availability of essential habitat elements. Studies of 
mountain plovers on winter habitat in California have shown that winter 
site fidelity is poorly developed, and flocks of birds may travel over 
55 km (33 miles (mi)) between alternate foraging sites. Further, the 
mountain plover demonstrates an affinity for sites with a mosaic of 
short vegetation and bare ground. These attributes are subject to 
change annually in proportion and distribution due to either natural 
(e.g., fire, succession, seasonal precipitation) or human-caused (e.g., 
grazing intensity, range management) events. It would be impractical to 
designate specific geographic locations as critical habitat when the 
essential elements of that habitat may shift temporally and spatially 
across the landscape.
    Designation of critical habitat may provide a minor benefit in that 
it may assist in securing funding or acquiring land for conservation. 
In some cases, the designation of critical habitat may provide some 
benefits to a species by identifying areas important to the species' 
conservation, including habitat that is not presently occupied and that 
may require restoration efforts to support recovery. In some cases, the 
designation of critical habitat serves to notify Federal agencies of 
the presence of a listed species on land they administer. However, in 
this case, the Service, the BLM, and the Forest Service are all aware 
of the presence of the mountain plover on their lands, and in some 
cases currently perform affirmative management actions for this 
    Listing of the mountain plover as a threatened species also 
publicizes the present vulnerability of this species. Any designation 
of critical habitat for this species could reasonably be expected to 
increase the potential threat of vandalism or intentional destruction 
of the species habitat. In light of the vulnerability of this species 
to vandalism, the intentional destruction of its habitat (for example 
tilling nests, tilling grassland habitat), or disturbance caused by 
birders, the designation of critical habitat and the publication of 
maps providing locations and descriptions, as required for the 
designation of critical habitat, would reasonably be expected to 
increase the degree of threat to the species and its habitat, increase 
the difficulties of law enforcement, and further contribute to the 
decline of the mountain plover.
    Therefore, because the mountain plover is widely distributed on 
Federal lands and also may occur on private lands enrolled in Federal 
programs, the designation of critical habitat would provide little 
additional benefit beyond that provided by the jeopardy standard under 
section 7 regulations. In addition, the mountain plover's affinity for 
habitat elements that are likely to change frequently at both breeding 
and wintering locales strongly suggest that the biological value of any 
critical habitat designation would be short lived. Lastly, designation 
brings about the potential for an increased risk of intentional 
destruction of birds or their habitat. Consequently, we have determined 
that the designation of critical habitat for the United States 
population of the mountain plover is not prudent.

Available Conservation Measures

    Potential conservation measures to reverse the declining trend for 
this species might include incentives to landowners to leave some 
cultivated areas unplanted until plover eggs have hatched, grazing 
plans for native range that encourage high grazing intensity in plover 
nesting areas, haying and grazing on existing Conservation Reserve 
Program tracts to manage for the grass height and density required by 
nesting plovers, and seeding criteria for new Conservation Reserve 
Program tracts that would encourage establishment of native shortgrass 
prairie species in preference to taller grasses. The Service is 
initiating discussions with the Natural Resources Conservation Service 
to explore ways, such as the Conservation Reserve Enhancement Program, 
that these measures might be implemented on private land.
    Conservation measures provided to a species listed as endangered or 
threatened under the Act include recognition, recovery actions, 
requirements for Federal protection, and prohibitions against certain 
practices. Recognition through listing encourages and leads to the 
implementation of conservation actions by Federal, State, County, and 
private agencies, groups, and individuals. The Act provides for 
possible land acquisition and cooperation with the States, and requires 
that recovery actions be carried out for all listed species. Such 
actions are initiated by us following listing. The protection required 
of Federal agencies and the prohibitions against taking and harm are 
discussed, in part, below.
    Section 7(a) of the Act requires Federal agencies to evaluate their 
actions with respect to any species that is proposed or listed as 
endangered or threatened, and with respect to its critical habitat, if 
any is being designated. Regulations implementing this interagency 
cooperation provision of the Endangered Species Act are codified at 50 
CFR part 402. Section 7(a)(4) of the Act requires Federal agencies to 
confer informally with us on any action that is likely to jeopardize 
the continued existence of a proposed species or result in destruction 
or adverse modification of proposed critical habitat. If a species is 
listed subsequently, section 7(a)(1) provides that all Federal agencies 
shall utilize their authorities in furtherance of the purpose of the 
Act by carrying out programs for the conservation of species listed 
pursuant to the Act. Further, section 7(a)(2) of the Act requires 
Federal agencies to ensure that activities they authorize, fund, or 
carry out are not likely to jeopardize the continued existence of such 
a species or to destroy or adversely modify its critical habitat. If a 
Federal action may affect a listed species or its critical habitat, the 
responsible Federal agency must enter into formal consultation with us. 
Consequently, Federal listing will cause all Federal agencies to 
consider mountain plover conservation needs during their review of 
activities they may fund, authorize, or carry out.
    Section 10(a)(2)(A) of the Act allows for the incidental taking of 
federally listed species on private lands, where no Federal agency 
action exists, provided the applicant adopts a habitat conservation 
plan (HCP) to minimize the degree of take while furthering the 
conservation of the species. We anticipate that HCPs will be requested 
should the mountain plover become a federally listed species. We 
encourage and will participate in the development of HCPs to ensure 
that mountain plovers can be conserved throughout their range while 
authorizing incidental take associated with otherwise lawful 
activities. We believe that habitat modification techniques shown to be 
effective for the mountain plover can be incorporated into HCPs that 
may be implemented at breeding or wintering locales.

[[Page 7599]]

    A unique Memorandum of Agreement (MOA) was signed in 1995 by the 
Secretary of the Department of the Interior and the Governor of 
Colorado. The purpose of the MOA is to address the conservation needs 
of declining species in Colorado, with a goal of preventing their 
decline to a point at which Federal listing could be needed. The 
mountain plover is mentioned specifically in this MOA, and a work group 
now exists to address its needs. We have participated diligently with 
the work group to pursue the goals of the MOA and believe that the MOA 
can be an effective vehicle to promote and implement mountain plover 
conservation actions in Colorado, and perhaps encourage similar 
conservation actions in adjoining States.
    Mountain plovers occur on lands administered by the Service, Forest 
Service, BLM, and other agencies. For all public lands where mountain 
plovers occur, the Act would require the appropriate land management 
agency to evaluate potential impacts to mountain plovers that may 
result from activities they fund, authorize, or carry out. The Act 
requires consultation under section 7 of the Act for activities on 
private lands, including tribal lands, that may impact the survival and 
recovery of the mountain plover, if such activities are funded, 
authorized, or permitted by Federal agencies. The Federal agencies that 
may be involved as a result of this proposed rule include the Service, 
BLM, Forest Service, APHIS, Bureau of Indian Affairs, Natural Resources 
Conservation Service, Farm Services Agency, Department of Defense, 
Department of Energy, Department of Justice, and the EPA.
    Federal agency actions that may require conference and/or 
consultation as described in the preceding paragraphs include:
    (1) Removing, thinning or altering vegetation. Mountain plover nest 
sites have short vegetation, while taller vegetation may be required by 
chicks for shade and hiding cover;
    (2) Modifying topography and soils at breeding sites. Mountain 
plover nest sites are on land with less than 5 percent slope, and 
usually have at least 30 percent bare ground. Any activity that alters 
one of these characteristics would likely be detrimental;
    (3) Domestic livestock grazing management. The current state of 
knowledge indicates that domestic livestock grazing intensity 
influences the quality of mountain plover habitat. Review of grazing 
management proposals would be necessary to determine their 
compatibility with the mountain plover and its habitat. Those proposals 
that adversely affect a species or its habitat (e.g., altering 
vegetative structure or composition that destroys suitable habitat 
characteristics) would require reasonable and prudent alternatives or 
reasonable and prudent measures to minimize incidental take;
    (4) Controlling burrowing rodents. Prairie dogs, giant kangaroo 
rats, and California ground squirrels are known to create suitable 
conditions for mountain plovers;
    (5) Conversion of untilled grassland to tilled land. While mountain 
plovers are found on grasslands, they are attracted to cultivated lands 
for foraging opportunities and nesting, which makes them vulnerable to 
effects from tilling and pesticide application. Therefore, cultivated 
lands are likely a reproductive sink. Therefore, Federal programs that 
encourage conversion of grasslands to cultivated land could be 
detrimental to the conservation of the mountain plover;
    (6) Human activities near nesting mountain plovers. Federal 
proposals or permits for activities that would create disturbance 
during the nesting period could interfere with normal nesting behavior 
and result in the death of eggs, chicks and/or adults;
    (7) Registration of pesticides. We have documented that numerous 
pesticides are toxic to birds during field application and some of 
these pesticides are used while mountain plovers occupy breeding and 
wintering habitats;
    (8) Oil, gas, or mineral development on known nesting or wintering 
    The Act and implementing regulations found at 50 CFR 17.21 and 
17.31 set forth a series of general prohibitions and exceptions that 
apply to all threatened wildlife. The prohibitions, codified at 50 CFR 
17.21 and 17.31, in part, make it illegal for any person subject to the 
jurisdiction of the United States to take (includes harass, harm, 
pursue, hunt, shoot, wound, kill, trap, capture, or collect; or attempt 
any of these), import or export, ship in interstate commerce in the 
course of commercial activity, or sell or offer for sale in interstate 
or foreign commerce any such species. It also is illegal to possess, 
sell, deliver, carry, transport, or ship any such wildlife that has 
been taken illegally. Certain exceptions apply to agents of the Service 
and conservation agencies.
    Under certain circumstances, permits may be issued to carry out 
otherwise prohibited activities involving threatened wildlife species. 
Regulations governing permits are codified at 50 CFR 17.32. Such 
permits are available for scientific purposes, enhancement of 
propagation or survival of the species, educational purposes, 
zoological exhibition, incidental take in connection with otherwise 
lawful activities, and/or other special purposes consistent with the 
purposes of the Act. Requests for copies of the regulations regarding 
listed wildlife and inquiries about prohibitions and permits may be 
addressed to the Permits Branch, U.S. Fish and Wildlife Service, P.O. 
Box 25486, Denver Federal Center, Denver, Colorado 80225-0207 
(telephone 303/275-2370; facsimile 303/275-2371).
    We adopted a policy on July 1, 1994 (59 FR 34272), to identify to 
the maximum extent practicable, at the time a species is proposed for 
listing, those activities that would or would not constitute a 
violation of section 9 of the Act. The intent of this policy is to 
increase public awareness of the effect of the listing on proposed and 
ongoing activities within a species' range. We believe that the actions 
listed below would probably not result in a violation of section 9:
    (1) Activities authorized, funded, or carried out by Federal 
agencies (e.g., grazing management, agricultural conversions, range 
management, rodent control, mineral development, oil and gas 
development, road construction, human recreation, and pesticide 
application) when such activity is conducted in accordance with any 
reasonable and prudent measures given by us in accordance with section 
7 of the Act;
    (2) Within the breeding range, normal farming practices on 
cultivated lands, prescribed burns, and construction/maintenance 
activities (e.g., fences, power lines, pipelines, and utility lines) 
conducted when mountain plovers are not present on breeding habitat. 
The period when activities would not impact mountain plovers may vary 
at specific locations, but would usually fall between August 10 and 
April 1;
    (3) Within the wintering range, normal winter farming practices on 
sod farms and tilled cropland;
    (4) Casual, dispersed human activities on foot or horseback at 
breeding and wintering habitats (e.g., waterfowl hunting, bird 
watching, sightseeing, photography, camping, and hiking);
    (5) Normal, routine domestic livestock grazing, herding, and 
inspecting, including maintenance of livestock improvement structures; 
    (6) Application of pesticides in accordance with label restrictions 
or County Bulletins that have resulted from Endangered Species Act 
    We believe that the actions listed below might potentially result 
in a violation of section 9; however, possible

[[Page 7600]]

violations are not limited to these actions alone:
    (1) Unauthorized collecting or handling of the species;
    (2) The unauthorized destruction of mountain plovers including 
adults, nests, eggs, and/or young by any human activity, or any human 
activity resulting in actual death or injury to the species by 
significantly modifying essential behavioral patterns (e.g., breeding, 
feeding, sheltering). Examples of human activities may include discing 
or tilling on cultivated land during the breeding season; land 
leveling, conversion of grassland to cropland, road construction, water 
development, range management, mineral development, or off-highway 
vehicle use, in any season on non-cultivated lands that serve as 
nesting habitat;
    (3) Application of pesticides in violation of County Bulletins or 
label restrictions; and
    (4) Interstate or foreign commerce (commerce across State or 
international boundaries) and import/export (as discussed earlier in 
this section) without having obtained a threatened species permit. 
Permits to conduct these activities are available for purposes of 
scientific research and enhancement of propagation or survival of the 
    Questions regarding whether specific activities, such as changes in 
land use, will constitute a violation of section 9 should be directed 
to the Assistant Field Supervisor (see ADDRESSES section).
    The prohibition against intentional and unintentional ``take'' of 
listed species applies to all landowners regardless of whether or not 
their lands are within critical habitat (see 16 U.S.C. 1538(a)(1), 
1532(1a), and 50 CFR 17.3). Section 10(a)(1)(B) authorizes us to issue 
permits for the taking of listed species incidental to otherwise lawful 
activities such as agriculture, surface mining, and urban development. 
Incidental take permits must be supported by an HCP that identifies 
conservation measures that the permittee agrees to implement to 
conserve the species, usually on the permittee's lands. For example, 
no-till practices that leave tall stubble may successfully cause 
plovers to avoid cropland. On fallow ground, the type of farm implement 
used and the timing of the use may be significant in producing more 
plovers. These and other techniques to avoid plovers or produce plovers 
can be examined by producers in the development of an HCP. A key 
element in our review of an HCP is a determination of the plan's effect 
upon the long-term conservation of the species. We would approve an 
HCP, and issue a section 10(a)(1)(B) permit, if the plan would minimize 
and mitigate the impacts of the taking and would not appreciably reduce 
the likelihood of the survival and recovery of that species in the 

Public Comments Solicited

    We intend that any final action resulting from this proposal will 
be as accurate and as effective as possible. Therefore, comments or 
suggestions from the public, other concerned governmental agencies, the 
scientific community, industry, or any other interested party 
concerning this proposed rule are hereby solicited.
    We are seeking comments particularly concerning:
    (1) Biological, commercial trade, or other relevant data concerning 
any threat (or lack thereof) to the mountain plover;
    (2) The location of any additional breeding, wintering, or 
migration sites, including areas in Mexico and Canada;
    (3) Additional information concerning mountain plover distribution, 
population size and/or population trend;
    (4) Information regarding current or planned land uses, and their 
possible beneficial or negative impact to the mountain plover or its 
habitat (e.g., agricultural conversions, oil and gas development, land 
exchanges, range management, habitat conservation plans, conservation 
    (5) Information regarding mountain plovers on their wintering 
habitats (e.g., preferential use of natural versus agricultural 
habitats, habitat distribution and abundance, daily routines, night 
roosts, site fidelity, population abundance);
    (6) Additional biological or physical elements that best describe 
mountain plover habitat, that could be considered essential for the 
conservation of the mountain plover (e.g., burrowing rodent colonies, 
vegetation, food, topography);
    (7) Information relative to mountain plover distribution and 
productivity on cultivated lands, shortgrass prairie, and shrub-steppe 
    (8) Alternative farming practices that will reduce or eliminate the 
take of mountain plovers;
    (9) Other management strategies that will conserve the species 
throughout its range; and
    (10) Information regarding the benefits of critical habitat 
    Final promulgation of the regulations on this species will take 
into consideration the comments and any additional information received 
by us. Such communications may lead to a final regulation that differs 
from this proposal.
    The Act provides for one or more public hearings on this proposal, 
if requested. Requests must be received within 45 days of the date of 
publication of the proposal in the Federal Register. Such requests must 
be made in writing and addressed to the Assistant Field Supervisor (see 
ADDRESSES section).
    Executive Order 12866 requires each agency to write regulations 
that are easy to understand. We invite your comments on how to make 
this rule easier to understand including answers to questions such as 
the following: (1) Are the requirements in the rule clearly stated? (2) 
Does the rule contain technical language or jargon that interferes with 
its clarity? (3) Does the format of the rule (grouping and order of 
sections, use of headings, paragraphing, etc.) aid or reduce its 
clarity? (4) Would the rule be easier to understand if it were divided 
into more (but shorter) sections? (5) Is the description of the rule in 
the SUPPLEMENTARY INFORMATION section of the preamble helpful in 
understanding the rule? What else could we do to make the rule easier 
to understand?
    Send a copy of any comments that concern how we could make this 
rule easier to understand to: Office of Regulatory Affairs, Department 
of the Interior, room 7229, 1849 C Street, NW, Washington, DC 20240. 
You may also e-mail the comments to this address: Execsec@ios.doi.gov.

National Environmental Policy Act

    We have determined that Environmental Assessments and Environmental 
Impact Statements, as defined under the authority of the National 
Environmental Policy Act of 1969, need not be prepared concerning 
regulations adopted pursuant to section 4(a) of the Act of 1973, as 
amended. A notice outlining our reasons for this determination was 
published in the Federal Register on October 25, 1983 (48 FR 49244).

Required Determinations

    This rule does not contain any new collections of information other 
than those already approved under the Paperwork Reduction Act, 44 
U.S.C. 3501 et seq., and assigned Office of Management and Budget 
clearance number 1018-0094. An agency may not conduct or sponsor, and a 
person is not required to respond to a collection of information, 
unless it displays a currently valid control number. For additional 
information concerning permit and associated requirements for 
threatened species, see 50 CFR 17.32.

[[Page 7601]]

References Cited

    A complete list of all references cited herein, as well as others, 
is available upon request from the Assistant Field Supervisor (see 
ADDRESSES section).
    Author. The primary author of this proposed rule is Robert Leachman 
(see ADDRESSES section).

List of Subjects in 50 CFR Part 17

    Endangered and threatened species, Exports, Imports, Reporting and 
recordkeeping requirements, Transportation.

Proposed Regulation Promulgation

    Accordingly, we propose to amend 50 CFR Part 17, as set forth 


    1. The authority citation for Part 17 continues to read as follows:

    Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1554; 16 U.S.C. 
4201-4245; Pub. L. 99-625, 100 Stat. 3500, unless otherwise noted.

    2. Amend Sec. 17.11(h) by adding the following, in alphabetical 
order under ``BIRDS'' to read as follows:

Sec. 17.11  Endangered and threatened wildlife.

* * * * *
    (h) * * *

                        Species                                                    Vertebrate
--------------------------------------------------------                        population where                                  Critical     Special
                                                            Historic range       endangered or         Status      When listed    habitat       rules
           Common name                Scientific name                              threatened

                   *                  *                  *                  *                  *                  *                  *
Plover, mountain.................  Charadrius montanus.  U.S.A. (western)...  Entire.............  T                                     NA           NA

                   *                  *                  *                  *                  *                  *                  *

    Dated: December 23, 1998.
Jamie Rappaport Clark,
Director, Fish and Wildlife Service.
[FR Doc. 99-3628 Filed 2-12-99; 8:45 am]