Introduction

Native to the prairies of North America, the Chestnut-collared Longspur bred historically at sites recently grazed by bison (Bison bison) or disturbed by fire. Even today, this species avoids nesting in areas protected from grazing, instead preferring pastures and mowed areas such as airstrips, as well as grazed native prairie habitats. Breeding territories are sometimes clumped together, so this bird may at times be locally abundant. But as native prairie has disappeared, so has the Chestnut-collared Longspur. Breeding populations in Nebraska and Minnesota, for example, have been much reduced, and this species no longer breeds in Kansas, where it was described as abundant in the 1870s.

In fall, this species moves south from its breeding grounds to winter primarily on the dry grasslands, deserts, and plateaus of the south-central and southwestern United States and Mexico. Wintering flocks, with densities as high as 166 individuals/ha, feed on grains such as wheat and seeds of native plants.

The male Chestnut-collared Longspur defends his territory by performing Aerial Song Displays—flying upward to a height of 10 to 15 meters, then spreading his tail and singing during descent. Male plumage is conspicuous with black belly and cap, deep chestnut collar, and yellow cheek; the buff-colored female, by contrast, blends cryptically into its prairie habitat. Double-brooded and socially monogamous, this is one of many species in which extra-pair copulations occur; most extra-pair young are found in second brood nests.

Generally, this species has not been well studied and there are many gaps in our knowledge of its migratory and wintering biology. Major studies of breeding populations include those by Harris (1944) in Manitoba; Fairfield (1968), Hussell (1972), and Maher (1973), in Saskatchewan; and Wyckoff (1983, 1986a, b) in North Dakota and Minnesota.