The Late Prehistoric–Early Historic Game Sink in the Northwestern United States

Historical data provide valuable information on ecosystem structure, function, and processes. The number of big game killed by the Corps of Discovery in 1805–1806 and recorded by Lewis and Clark suggests that ungulates were abundant in central and eastern Montana and rare in western Montana, central Idaho, and southeastern Washington during the early nineteenth century. Paleoecologists Paul Martin and Chris Szuter conclude that this difference was a function of human predation. They support their conclusion that ungulates would have been abundant in southeastern Washington had humans not hunted them by arguing that the nineteenth-century livestock industry was successful without supplemental feeding. The livestock industry was, however, not consistently successful until artificial feeding was initiated. Archaeological data from eastern Washington indicate that ungulates have been taken by human hunters more frequently than small-mammal prey throughout the last 10,000 years and that ungulates decreased relative to small mammals coincident with changes in climate. Bison ( Bison bison ) and elk ( Cervus canadensis ) were present in eastern Washington throughout the Holocene, but bison were abundant there only during a cooler and moister period; elk have been abundant only in the twentieth century, subsequent to transplants and the extermination of predators. Geographic variation in the abundance of bison across Montana, Idaho, and eastern Washington has been influenced by human predation but has also been influenced by biogeographic history, habitat differences, and climatic change. El Sumidero de Especies de Caza del Prehistórico Tardío/Histórico Temprano del Noroeste de los Estados Unidos Resumen: Los datos históricos proveen información valiosa sobre las estructuras de los ecosistemas, sus funciones y procesos. El número de animales de caza grandes que fueron sacrificados por las tropas de descubrimiento en 1805-1806 y registradas por Lewis y Clark sugieren que los ungulados eran abundantes en Montana central y oriental y raros en Montana occidental, Idaho central y el sudeste de Washington durante los inicios del siglo diecinueve. Los paleontólogos Paul Martin y Chris Szuter concluyen que esta diferencia fue causada por la depredación humana. Ellos apoyan su conclusión de que los ungulados podrían haber sido abundantes en el sudeste de Washington si los humanos no los hubieran cazado argumentando que la industria de la ganadería del siglo diecinueve exitosa sin alimento suplementario. Sin embargo, la industria de la ganadería no fue consistentemente exitosa hasta que se inició la alimentación artificial. Los datos arqueológicos de Washington oriental indican que los ungulados fueron eliminados por los cazadores humanos mas frecuentemente que las presas pequeñas de mamíferos a lo largo de los últimos 10,000 años y que la disminución de ungulados, relativa a la de mamíferos pequeños coincidió con cambios en el clima. El bisonte ( Bison bison ) y el alce ( Cervus canadiensis ) estuvieron presentes en Washington oriental a lo largo del Holoceno, pero los bisontes fueron abundantes solo durante un periodo mas frío y húmedo; los alces habían sido abundantes solo en el siglo veinte subsecuente a los transplantes y a la exterminación de los depredadores. La variación en la abundancia de alces a lo largo de Montana, Idaho y el oriente de Washington estuvo influenciada por la depredación humana, pero también por la historia biogeográfica, las diferencias en hábitat y el cambio climático. * email [email protected] Paper submitted February 18, 2000; revised manuscript accepted March 28, 2001. 74 The Northwest Game Sink Lyman & Wolverton Conservation Biology Volume 16, No. 1, February 2002 Introduction Ecologists and conservation biologists recognize the value of historic data for understanding the structure, function, and processes of ecosystems (Meine 1999). Early historic documents describing the flora and fauna of an area help explain the appearance of modern ecosystems and why these biotas are not often good reflections of their pre-Euroamerican settlement condition. Efforts to reconstruct early historic ecosystems on the basis of historical data are valuable, but are fraught with difficulty. We evaluated a recent example of such an effort to underscore some of the difficulties. In an attempt to characterize early historic ecosystems, paleoecologists Paul Martin and Christine Szuter (1999 a , 1999 b ) refer to ethnohistorian Harold Hickerson’s (1965:43) concept of an intertribal “buffer zone,” an area he characterizes as “contested territory on the frontiers between tribes which, except for communal [game] drives, was normally unoccupied.” Martin and Szuter argue that records of big game killed by the Corps of Discovery led by Meriwether Lewis and William Clark (1804–1806) indicate that a kind of buffer zone (a “war zone”) where large game was abundant existed between approximately the Montana–North Dakota border on the east and west-central Montana on the west. They further suggest that a “game sink” where big game was scarce existed between west-central Montana and central Washington ( Fig. 1). Martin and Szuter conclude that big game was abundant in the war zone because it was largely free from year-round hunting by Native Americans, whereas big game was scarce in the game sink because of continuous human predation. They offer this interpretation as an alternative to the more typical ones that local game abundances “reflect the changing productivity of the habitat” (Martin & Szuter 1999 b :38) and that humans who occupied North America prior to its colonization by Europeans conserved, either intentionally or incidentally, local game populations (Todd & Elmore 1997). Martin and Szuter conclude that, were it not for human hunting in southeastern Washington and central Idaho (the game sink), ungulates would have been abundant—perhaps as abundant as they were in the war zone of Montana—in 1805–1806 when the Corps of Discovery passed through the area. This conclusion assumes much about the prehistoric abundances of ungulates. If Martin and Szuter are correct, then within the game sink ungulates were abundant some time after the initial arrival of humans about 11,000 B . P . (Ames et al. 1998), and at some time subsequent to that arrival ungulates became less abundant as a result of human predation rather than, say, environmental change. Similarly, within the war zone ungulates should have been abundant when humans first arrived, should subsequently have been depressed as a result of human predation, and finally should have increased coincident with the formation of the war zone. As part of the basis for drawing the conclusion they do, Martin and Szuter refer to the history of the livestock industry in eastern Washington and argue that, because domestic ungulates survived there in abundance during the late nineteenth century, wild ungulates would have survived there in abundance were it not for hunting. We evaluate Martin and Szuter’s “war zone and game sink” hypothesis in three ways. First, we reexamine Lewis and Clark’s data and suggest that abundances of ungulates were varied within Martin and Szuter’s war zone and game sink and that the border between these areas is neither abrupt nor obvious. Second, we suggest that the livestock industry was not completely successful until supplemental winter feeding was initiated. Third, we present archaeological evidence suggesting that ungulate abundances in the game sink did not change in the manner or at the time presumed by Martin and Szuter’s model. Finally, we briefly review traditional exFigure 1. Martin and Szuter’s (1999b) model of a war zone where game was abundant in Montana and a game sink where game was scarce in western Montana, central Idaho, and southeastern Washington; A, Fort Clatsop; B, Celilo Falls; C, Lolo Pass; D, Traveler’s Rest; E, Lemhi Pass; F, Camp Fortunate; G, Three Forks; H, Great Falls; I, Williston.