Introduction

Ross’s Goose is the smallest of three varieties of white (snow) geese that breed in North America. First reported as the “horned wavey” by the explorer Samuel Hearne (1795) during his travels in the interior of the central Canadian Arctic between 1770 and 1771, the species was not described for science until almost a century later (Cassin 1861). Its arctic nesting grounds remained unknown for another 80 years until Angus Gavin, a manager with the Hudson’s Bay Company, located them in the Perry River region of the central Canadian Arctic in 1940. These were the last of the white goose breeding areas to be discovered in North America (Cartwright 1940, Gavin 1940). Additional nesting colonies were found in the central Arctic by Hanson et al. (1956), Ryder (1969a), Alisauskas and Boyd (1994), and Kerbes (1994).

Currently, about 95 percent of all Ross’ Geese nest in the Queen Maud Gulf Migratory Bird Sanctuary in the central Canadian Arctic (Kerbes 1994). Small numbers also nest along the west and south coasts of Hudson Bay, on Southampton and Baffin islands, and in the western Arctic. The main wintering area for the species is presently in the Central Valley of California, though increasing numbers winter in Arkansas, Louisiana, New Mexico, Texas, and the north-central highlands of Mexico (Turner et al. 1994). This species seldom associates with the largest snow goose, Greater Snow Goose (Chen caerulescens atlantica), which breeds farther north on high arctic islands and winters farther north and east (Atlantic Coast) than does Ross’s Goose, but it is often found in the company of the intermediate-sized Lesser Snow Goose (C. c. caerulescens) which breeds and winters at similar latitudes, and during the winter and early spring migration in California, with the Cackling Goose (Branta canadensis minima).

Ross’ Geese nest in colonies, usually interspersed with Lesser Snow Geese. Nests are on the ground, usually on sparsely vegetated islands and surrounding mainland areas of shallow arctic lakes (Ryder 1969a, Kerbes 1994), less frequently on riverine and offshore islands (Alisauskas and Boyd 1994). This is a grazing species that feeds on grasses, sedges, and small grains.

Before 1900 and in the early 1900s, this goose was considered a rare species, possibly a consequence of open market hunting in California—it was commonly seen in the markets of San Francisco, Sacramento, Stockton, and Los Angeles (Grinnel et al. 1918). In 1931, when its numbers were estimated at 5,000 to 6,000 individuals, legislation was passed to prohibit hunting. Subsequent accidental and illegal killing, however, was thought to be a continued serious threat. Cahalane et al. (1941), in their 1940 report to the American Ornithologists’ Union Committee on Bird Protection, recommended (unsuccessfully) closing the Sacramento Valley in California to all white goose hunting, to protect the Ross’s Goose. In the 1960s and 1970s, Alberta and Saskatchewan initiated a late white goose hunting season in an effort to reduce hunting mortality of this species. Total number of birds have increased from a recorded low of 2,000–3,000 in the early 1950s (Lloyd 1952) to more than 188,000 recorded nesting in the Queen Maud Gulf Migratory Bird Sanctuary in 1988 (Kerbes 1994). The breeding biology of this species is known from studies within this sanctuary at Arlone Lake (67°22' N, 102°10' W; Hanson et al. 1956, Ryder 1967) and Karrak Lake (67°15' N, 100°15' W; Ryder 1972, McLandress 1983a, Slattery 1994). Studies of migration include those by Dzubin (1965) and Melinchuk and Ryder (1980) and on the wintering areas by McLandress (1979). Since 1955, numbers and locations of wintering Ross’ Geese have been estimated by the U.S. Fish and Wildlife Service during annual winter inventories of waterfowl.

Based on morphology, behavior, and genetic analyses, this goose is closely related to other anserine geese, particularly Lesser Snow Goose. Locations of spirit and skeletal collections are, respectively, in Wood et al. 1982 and Wood and Schnell 1986 .