≡
Mountain Plover
Charadrius montanus
NatureServe conservation status
Global (G-rank): G3
State (S-rank): S1B
- Reason: This species is a rare, localized nester in the Uinta Basin of Duchesne and Uintah counties. Breeding in Utah was confirmed in 1978 and more recently in 1993 and has been observed in every breeding season since then. The species is also a rare migrant occasionally encountered in various parts of the state.
External links
General information
Distribution: As cited in Knopf (1996): The mountain plover, Charadrius montanus, breeds in eastern, central, and southwestern Montana (Bergeron et al. 1992), tablelands of Wyoming (Oakleaf et al. 1992), eastern Colorado (including Fremont and Park counties; Andrews and Righter 1992), northeast and locally to west-central New Mexico (south to Roswell area and west to Fence Lake area; Hubbard 1978), and in Oklahoma and Texas panhandles. An isolated breeding population occurs in Davis Mountains, Texas. Breeding records defining the periphery of its range include Catron (Johnson and Spicer 1981), San Juan (Tolle 1976), and Valencia (Hubbard 1978) Counties, NM; Park County, NE (Clausen 1990, FLK), and the Lost River area of southern Alberta (Soper 1941, Wershler 1987). Three nests were found in 1993 in Duchesne County, UT (Day 1994), and additional nesting activity was found in 1994 and 1995.
In Utah it has been recorded as a casual migrant in Box Elder, Weber, Salt Lake, and Daggett counties (Woodbury et al. 1949). There are six documented historical sightings in the Uinta Basin (White et al. 1983). In 1978, Dan Gardner of the Bureau of Land Management photographed one adult and a nearby nest with three eggs (UDWR 1994, unpublished report). A pair of plovers was observed on 11 April 1989 on a sage brush bench about 1.6 k (1 mi) east of Pelican Lake, Uintah County (D. A. Boyce, USFS, pers. comm.). There were seven sightings of mountain plovers made during Utah Division of Wildlife Resources whitetail prairie dog (Cynomys leucurus) mapping surveys of Eightmile Flat, Uintah County in 1992 (UDWR 1992, unpublished report). Survey work in 1993 confirmed a population of unknown size in the same area (Day 1994). Population information from survey work done from 1993-98 is reported in Table 8.
As cited in Knopf (1996): Winter range. Birds disperse widely across western and southern Great Plains in late summer and early fall. Most birds winter from north-central California to Mexico border, primarily in the Sacramento, San Joaquin, and Imperial valleys, with some birds on Pacific slopes in southern counties (Knopf and Rupert 1995).
Ecology: Most birds wintering in California depart mid-March in flocks of less than 100 birds in a west-east spring migration, and seem to make a nonstop flight to the breeding grounds. Plovers regularly arrive on the Pawnee National Grassland around March 17 (Knopf and Rupert 1995), and have been observed in Duchesne County, Utah as early as April 9. It is likely that plovers arrive in Utah earlier than the date of observation reported here. Mountain plover diet consists mainly of arthropods. Baldwin (1971, as cited in Knopf 1996) found ground-dwelling beetles to account for 60% of food mass eaten, grasshoppers and crickets 24.5% and ants 6.6%. A study done of the plover diet on the wintering ground indicated that birds may be more flexible in food selection than previously thought (Knopf 1998). This species is associated with disturbed prairie and semidesert habitats. It prefers areas with 30% bare ground (Knopf and Miller 1994). Territories on the breeding ground are about 16 hectares each though some boundaries may overlap. Some birds will return to the same territory used the previous year (Graul 1973). In Utah nests of nearest neighbors in 1998 were located about 240-370 meters apart. The nest is a simple scrape on the ground (Graul 1973). Clutch size is typically 3 (Knopf 1996). Known predators to the mountain plover include thirteen-lined ground squirrel, swift fox, coyote, Swainson's Hawk, Prairie Falcon and Loggerhead Shrike (Knopf 1996). Most plovers breeding in Weld County, Colorado have departed by August 1 (Knopf and Rupert 1996); in Utah birds have been observed with young until August 14. Exact departure dates are not known.
Phenology
These birds are generally crepuscular foragers, spending much of midday relatively inactive.
Species range
This species is known to nest in the eastern Uinta Basin. Day (1994) reported three nests that were found during 1993 in Duchesne County, and nesting was documented during 1994, 1995, and 1996. Nesting by this species has since been confirmed in Uintah County and is possible in Grand County.
Migration
Generally arrival in northern nesting range is during mid-March to mid-May (Bent 1929); in Canada as late as late April (Wershler 1987). Usually these birds begin arriving in breeding areas in northeastern Colorado in mid-March; they depart in mid to late July (Knopf and Rupert 1995, Knopf 1996), then wander for a few months in the southern Great Plains region (Knopf 1996), and arrive at winter range in southern California in October. They depart again in mid-March, and migrate to breeding areas rapidly (Knopf 1996).
Habitat
Walters and Sorensen (1983) gave its habitat in migration through Utah as sagebrush-rabbitbrush (at lower elevations). Behle et al. (1985) considered it to be a "transient found mostly at upland moist meadows and seepage areas". Day (1994) described the general area in which the first nests of this species were found in Utah as ". . . a highly varied topography of sand/gravel washes, dry upland benches dominated by low-growing shrubs of Artemesia [sic] sp. and Chrysothamnus sp., rocky cliffs, and outcroppings. Greasewood (Sarcobatus vermiculatus) predominates in ravines and low-lying areas. Indian rice grass (Oryzopsis hymenoides), galleta (Hilaria jamesii) and blue grama (Bouteloua gracilis) are common understory grasses. . . . Elevations vary from approximately 1,524 m to 1,920 m." Day (1994) further described the particular areas used by this species: "A nest . . . was discovered . . . in a slightly sloped, scarified area approximately 60 m from a producing [oil] well. Another nest . . . was . . . in a flat area of sparse grasses . . . [or] in a large, flat area of sparse, low-growing grasses 12 m from an unimproved dirt road. A third nest . . . was . . . located . . . in moderately dense sagebrush (Artemesia [sic] nova) . . .. Broods primarily used moderately dense, low-growing (<30 cm) shrub complexes with open understory, which differs from the open, short-grass habitat most researches describe . . .. Plovers also were seen on and around the many [oil] well pads and dirt access roads . . .."
Food habits
This opportunistic bird feeds primarily on insects (grasshoppers, crickets, beetles, flies, ants). It takes prey from the ground, and selects different food items at different locales (Knopf, in prep.).
Ecology
These are gregarious birds, outside breeding season; they forage and roost in loose flocks of changing composition. Flock size may exceed 1000 on southern Great Plains in late summer; site fidelity seemed poorly developed in winter range in southern California, but the winter survival rate was high (Knopf and Rupert 1995). Density at Charles M. Russell National Wildlife Refuge, Montana, was 16.2 breeding plovers per 100 ha in prairie dog towns, 0.28 birds per sq km in the entire area (Olson 1984). The brood usually moves one to two km from the nest site in the first two to three days (Knopf and Rupert 1996). More than half of the clutches are lost to predators, mainly coyote (CANIS LATRANS) and swift fox (VULPES VELOX), and chicks also experience high rates of predation (Knopf 1996).
Reproductive characteristics
Breeding begins in late April in the south, mid May in the north. Nesting begins in April in Colorado (Knopf 1996). Full clutches occur mid-May to late June in north. Both sexes incubate three, sometimes two or four, eggs for 29 days, but not at the same nest. The female may lay second clutch while the male incubates the first clutch (Graul 1975). This behavior may be more the rule than the exception (Knopf, pers. obs.). Nestlings are precocial, and fledge in about 33-34 days. Adults nest alone or in loosely associated groups. Excessive rain and storms may destroy nests and result in taller vegetation that precludes birds from renesting in the vicinity as on the Pawnee National Grasslands in 1995 and 1997 (Knopf, unpub. data.).
Threats or limiting factors
The greatest threat to the nesting of this species in Utah is probably from degradation of breeding habitat. Oil and gas exploration and production in breeding areas may play some role in habitat loss. Knopf (1996) suggested that historical alteration of native grassland habitats caused by the "[r]emoval of native grazers--prairie dogs, bison, and pronghorns" may have led to the decline of this species.
References
- Text modified from: Parrish, J. R., F. P. Howe, and R. E. Norvell. 1999. Utah Partners in Flight draft conservation strategy. UDWR publication number 99-40. Utah Partners in Flight Program, Utah Division of Wildlife Resources, Salt Lake City.