Breeding Habitat:Grassland
Nest Type:Open-cup nesting passerine
Migration Status:Short distance migrant
Nest Location:Ground-low nesting
The Chestnut-collared Longspur is a characteristic breeding species of native mixed-grass prairies across the northern Great Plains. Along the western margin of its range, it is also found in tall short-grass habitats (Andrews and Righter 1992, Stewart 1975). It prefers taller and more mesic habitats than the McCown's Longspur, which becomes more prevalent in short-grass prairie communities.
Along BBS routes, the peak abundance of Chestnut-collared Longspurs is attained from southern Alberta and Saskatchewan into Montana and the Dakotas (Relative Abundance Map). Because of small sample sizes and incomplete coverage of BBS routes within portions of this range, the BBS trend estimates for this species should be viewed with caution. The 1966-1994 trends are generally non-significant; the only significant trend is a decline in South Dakota (Trend List). The 1966-1979 trends are generally in a positive direction, including significant increases in the Glaciated Missouri Plateau (S38) stratum, Western BBS Region, and Canada. In contrast the 1980-1994 trends are generally in a negative direction, with significant declines in South Dakota and the Great Plains Roughlands (S39) stratum. The trend map is a mosaic of increases and declines, perhaps with a predominance of declines (Trend Map). The survey-wide indices are variable, but with an increasing tendency through the late 1970s followed by a decline through the late 1980s (Survey-wide Annual Indices). Given the small sample sizes, the indices for states/provinces and strata tend to be variable with few consistent temporal patterns.
During the winter months, Chestnut-collared Longspurs are primarily found in grasslands from the Texas panhandle west to southeastern Arizona. Trends on CBCs are also limited by small sample sizes and should be viewed with caution; most are nonsignificant although an increase is indicated for Texas.
This species was formerly abundant in the native mixed-grass prairies, but its numbers have greatly declined since the nineteenth century as these habitats were converted to cultivated fields (Stewart 1975). Overgrazing is also detrimental to these longspurs, and contributed to these historic declines. Reduced wintering numbers have also been apparent in portions of Texas (Oberholser 1974). Since its preferred habitats continue to be lost to agriculture, the recent declines shown by the BBS are not unexpected. Whether or not the increasing tendency indicated during the 1970s was real or an artifact of the coverage of particular BBS routes during those years is unknown.
Andrews, R., and R. Righter. 1992. Colorado birds. Denver Mus.
Natur. Hist., Denver, CO. 442 pp.
Oberholser, H.C. 1974. The bird life of Texas, Vol. 2. Univ. of
Texas Press, Austin, TX. 538 pp.
Stewart, R.E. 1975. Breeding birds of North Dakota. Harrison
Smith, Lund Press, Minneapolis, MN. 295 pp.