Late Prehistoric and Early Historic Abundance of Columbian White-Tailed Deer, Portland Basin, Washington and Oregon, USA

Abstract

Two species of deer, each with 2 subspecies, are currently found in the Pacific Northwest, USA, of the contiguous lower 48 states (Smith 1991, Demarais et al. 2000, Kie and Czech 2000). In general, mule deer (Odocoileus hemionus hemionus) are found east of the crest of the Cascade Mountains of Washington and Oregon, whereas Columbian black-tailed deer (O. h. columbianus) are found to the west of that crest (Fig. 1). Today, Columbian white-tailed deer (O. virginianus leucurus) are found at the mouth of the Columbia River (southwest Washington and northwest Oregon, USA) and in southwestern Oregon (Smith 1985); the northwest white-tailed deer (O. v. ochrourus) is found in northeastern Oregon and eastern Washington (Ingles 1965, Johnson and Cassidy 1997, Verts and Carraway 1998). Increase in the abundance of both subspecies of white-tailed deer since 1935 has been attributed to modern management practices (O’Farrell and Hedlund 1972; Smith 1985). Historic records indicate that white-tailed deer were abundant in Washington and Oregon until the second half of the nineteenth century when habitat modification and human predation depleted the local population (Bailey 1936, Cowan 1936, Scheffer 1940). McCabe and McCabe (1984, 1997) imply that white-tailed deer may not have been present in the Portland Basin during the nineteenth century. Archaeological data indicate that white-tailed deer were indeed in this area (Livingston 1987). Other biologists (Bailey 1936, Verts and Carraway 1998) and some paleoecologists (Martin and Szuter 1999) suggest that deer were rare in western Oregon and western Washington in the early nineteenth century based on the fact that Lewis and Clark’s Corps of Discovery found very few deer during the winter of 1805–1806. Other paleoecologists suggest they may have been relatively abundant (Lyman and Wolverton 2002). Euroamerican settlement and forest clearing is thought to have resulted in larger deer populations, especially in the early twentieth century after harvest rates came under legal control (Brown 1961, Verts and Carraway 1998). The Columbian white-tailed deer was one of the original 78 species listed as federally endangered in 1968. Because the Columbian whitetailed deer is federally endangered, knowledge of its population history could assist in management decisions aimed at preservation of a viable population. Fluctuating population size during the nineteenth century raises the question of which ecological benchmark (Hunter 1996) wildlife managers should aim for. Archaeological evidence contributes to answering this question (Lyman and Cannon 2004). Livingston (1987) used discriminate function analysis to distinguish deer species represented by mandibular tooth rows recovered from 24 archaeological sites dating to the last 6,000 years in Oregon and Washington. Livingston’s data suggest that both the distribution and abundance of white-tailed deer decreased subsequent to Euroamerican settlement during the mid-nineteenth century. None of the specimens she examined, however, clearly postdated settlement of the area by Euroamericans. It was also unclear whether any of the specimens she studied dated to the late pre(Euroamerican) contact period. I present quantitative data from archaeological contexts on relative abundances of deer species that span the late precontact and the early postcontact periods. These data reveal the population history of Columbian white-tailed deer and Columbia black-tailed deer just prior to the influence of Euroamerican settlement and land use. I used these data to search for correlations between changes in deer population size and other variables such as human population density, climatic change, and habitat change in an effort to identify variables that might influence the survival of, particularly, the Columbian white-tailed deer population.