I came across a reference regarding buffalo and antelope in eastern Washington by George Gibbs in a report to General McClellan in 1854. Gibbs was hired to assess the First Nations peoples of Washington Territory prior to the treaties. Besides his reports on the tribes and tribal leaders, Gibbs made numerous observations about the Washington landscape. Regarding large game in eastern Washington Gibbs reported, "Of the larger game there is but little in their own country. The buffalo, it would seem, in former times penetrated at least occasionally thus far to the westward, though now they never come through the northern passes. We were informed by an old Iroquois hunter, at Fort Colville, who has been some forty-eight years in the company's service, that the last bull was killed some twenty-five years ago in the Grand Coulee."
This matches David Douglas (of Douglas fir fame) reporting eating buffalo tongue as a treat given to him by Wanapum people near present day Hanford in the 1820s.
These two reports strike me as reasonably reliable and extend the period of time bison were in Washington State to the 1820s. It is generally thought that previous bison populations came not through the northern passes, but via eastern Oregon and the Snake River plain of Idaho. The arrival of horses and guns combined with relatively marginal habitat and forage as well as poor connectedness to other populations brought about the demise of the bison in Washington State well before American settlement and well before the notorious wasteful slaughter of the herds on the high plains in the later part of the 1800s.
This matches David Douglas (of Douglas fir fame) reporting eating buffalo tongue as a treat given to him by Wanapum people near present day Hanford in the 1820s.
These two reports strike me as reasonably reliable and extend the period of time bison were in Washington State to the 1820s. It is generally thought that previous bison populations came not through the northern passes, but via eastern Oregon and the Snake River plain of Idaho. The arrival of horses and guns combined with relatively marginal habitat and forage as well as poor connectedness to other populations brought about the demise of the bison in Washington State well before American settlement and well before the notorious wasteful slaughter of the herds on the high plains in the later part of the 1800s.