Prehistoric Biogeography of White-Tailed Deer in Washington and Oregon

Abstract

White-tailed deer (Odocoileus virginianus) populations declined after 1875 in Washington and Oregon, and now appear to be expanding into territory they had not occupied in historic times. I used discriminant analysis to distinguish white-tailed from mule deer (0. hemionus) mandibles from 24 archaeological sites, allowing reconstruction of the prehistoric distribution of white-tailed deer. The prehistoric distribution shows that the post-1875 population decline may have been part of a long-term cycle, rather than a purely historical phenomenon associated with Euroamerican settlement. J. WILDL. MANAGE. 51(3):649-654 Species accounts for artiodactyls in Washington and Oregon (Bailey 1936, Dalquest 1948, Ingles 1965, Smith 1985) indicate that the range of white-tailed deer has diminished considerably since the American Northwest was settled by Euroamericans. Columbian white-tailed deer (0. v. leucurus) are now limited to remnant populations in southwestern Oregon and along the lower Columbia River (Smith 1985). They were once common from the mouth of the Columbia River east to the Dalles and John Day River area (Bailey 1936), and there is a possible record from Pasco, Washington (Taylor and Shaw 1929). They ranged up the Cowlitz River to the Puget Sound area (Suckley and Cooper 1860, Taylor and Shaw 1929, Allen 1942) and south into the Willamette Valley in Oregon (Bailey 1936). Northwest white-tailed deer (0. v. ochrourus) are restricted to higher-elevation forests of northeastern Washington and northeastern Oregon (Dalquest 1948, Ingles 1965, Payne et al. 1975, Asherin and Claar 1976) forming 2 populations separated by the most arid part of the Columbia Basin (Fig. 1). Historic records indicate that white-tailed deer were abundant in the Northwest until about 1875, when they rapidly disappeared (Bailey 1936, Cowan 1936, Scheffer 1940). White-tailed deer were thought to be extinct in western Washington (Taylor and Shaw 1929) until a small herd was discovered at the mouth of the Columbia River in 1939 (Scheffer 1940). Although white-tailed deer were abundant in southeastern Washington at the time the area was settled by Euroamericans, the population declined until they were reintroduced in 1938 (Larrison 1970). Pronghorn antelope (Antilocapra americana), elk (Cervus elaphus), bighorn sheep (Ovis canadensis), and bison (Bison bison) also have bee locally extirpated in many areas of the Northwest; most modern populations are reint oduced (Dalquest 1948, Ingles 1965, Lyman and Livingston 1983). Introduction of firearms and subsequent overhunting, introduction of new dis ases, and/or agriculture and other land use practices resulting in habitat loss are the most commonly cited processes by which Euroamericans caused artiodactyl decimation (Suckley and Cooper 1860, Cowan 1936, Schalk and Cleveland 1983:39-41). Both subspecies of white-tailed deer have increased in numbers and geographic distribution since 1935. Columbian white-tailed deer in Oregon have experienced a 15-fold increase in geographic range and a 10-fold increase in population size since 1939 (Smith 1985). Reports that white-tailed deer have spread south from Okan gan County into Chelan County, Washington, and observations of white-tailed deer in the central part of eastern Washington have led to the conclusion that the eastern subspecies also is expanding its range (O'Farrell and Hedlund 1972). Ecologically controlled changes in abundance and geographical distribution of migratory and nomadic species fall into 2 general categories; dramatic fluctuations over short periods of time with relatively little change over longer periods of time, and long-term shifts in response to environmental changes (Brown and Gibson 1983). To date, the decline in abundance and distribution of artiodactyls in Washington and Oregon has been viewed as a long-term decline in response to exploitation by Euroamericans or environmental change caused by Euroamerican settlement. Game management practices have been credited for recovery of the western populations (Smith 1985). However, the factors allowing the eastern populations to recover are