What happened to the buffalo in American history? That's one of the great stories of American environmental history in the West. And as I've said before, I think we've simplified it in a way that a close examination simply doesn't support. What we've tried to argue happened to buffalo, what most of the books—even some fairly recently published—have argued, is that buffalo existed in fairly undiminished numbers until after the Civil War. And then they were wiped out—however many a particular scholar argues there were, 40 million, or 60 million, or whatever—by the hide hunters, who were killing them for hides, for the market in the 1860s, 70s, and 80s.
When you look at the story of the buffalo in the 19th century, though, from a close and considered perspective, and especially when you use Native American sources to do it—that's one of the great lacks, I think, in a lot of the works done up till now, is that they didn't closely examine the Native American accounts—you begin to create a different picture of the buffalo.
First of all, and sort of fundamental to the whole story here, is that there probably were never, at any time in the history of buffalo in North America, 75 million of them, or 60 million of them, or even 40 million of them. And the simple reason for that is that when you look at the carrying capacity of the grasslands of North America—simply speaking, even in times of good weather—the grasslands of North America would not have supported that many buffalo.
The best way to do a determination of the grassland carrying capacity is to use the agricultural censuses for the 19th century. The good ones for the West start about 1890, and you can look at the censuses, for example, of 1890, 1900, and 1910, and extrapolate from livestock numbers—from horses, sheep, and cattle—and fairly quickly come to the conclusion that it simply wasn't possible for there to have been upwards of 40 million buffalo in the West. In fact, the grassland carrying capacity for large bovine animals probably was not much more than—depending on the weather cycle—between about 20 and 30 million animals.
So I think one part of the story is that we're almost certainly dealing with fewer animals than we thought before.