Photo courtesy National Park Service.

The expedition passed the mouth of the Niobrara on September 4, 1804. Two weeks later they noted the abundance of animal life in the region. September 17, 1804. Lewis: …this plane extends with the same bredth from the creek below to the distance of near three miles above parrallel with the river, an it is intirely occupyed by the burrows of the barking squiril heretofore descibed; this anamal appears here in infinite numbers and the shortness and virdue of grass gave the plain the appearance throughout it's whole extent of beautifull bowling-green in fine order.

More about the animals: September 17, 1804, Lewis: a great number of wolves of the small kind, halks [hawks] and some pole-cats were to be seen. I presume that those anamals feed on this squirril. …     this senery already rich pleasing and beatiful was still farther hightened by immence herds of Buffaloe, deer Elk and Antelopes which we saw in every direction feeding on the hills and plains. I do not think I exagerate when I estimate the number of Buffaloe which could be compre[hend]ed at one view to amount to 3000.

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