Holston describes the diet of the largely meat that trappers ate.
The Diet of the Mountain Men
Joel K. Kahn
"The trapper's diet, in particular, mirrored the Indian way of life. Both the mountain men and Indians had to live off the land. Their diet was largely meat, especially the flesh of the bison. Elk was probably second in consumption for most of the trappers. Less frequently, the mountain men ate deer, bear, antelope, horses, dogs, beaver, and other small game."