Native Americans in North America

Given the large impact that humans had on the bird fauna of Pacific islands, it should come as no surprise that they may have had a large impact in North America as well. Native Americans in California used fire extensively to manipulate the composition and structure of vegetation in ways that would enhance the abundance of game. Day [1, pp. 342-343] suggests that over much of New England native Americans

set fire to the woods to improve travelling and visibility; to drive or enclose game; and to destroy ``vermin'' ... It is certain that their activities destroyed the forest in some places and it is hardly to be doubted that they modified it over much larger areas.

Martin and Szuter [7] go even further. They analyze Lewis and Clark's journals and the records of other early European explorers of western North America. They identify a large region, ca. 120,000km$^2$,⁶as a ``war zone'' kept devoid of permanent occupation by the Blackfeet. This was an area in which game, bison, elk, and deer, were very abundant (Figure 4).

Figure 4: Hunting success (a) and distribution of Plains tribes (b) during the expedition of Lewis and Clark (from [7]).

• In a fifty day period along the upper Missouri, the Corps of Discovery was able to provide more than twice as much meat through hunting as was needed for daily consumption.

• After reaching the Continental divide they were able to provide less than half their daily needs through hunting of game. They bought dogs and horses from native peoples, who subsisted on salmon and a variety of roots, tubers, and corms.