Till about the middle of the 18th century the bison and the elk roamed the W.
The elephant, giraffe, lion, leopard, hyena, zebra, buffalo, gnu, quagga, kudu, eland and many other kinds of antelope roamed the plains; the rhinoceros, hippopotamus and crocodile lived in or frequented the rivers, and ostriches and baboons were numerous.
- Before the advent of the white man, herds of bison roamed the prairies, but these have disappeared,' and, with the exception of deer and bears, large game is to be found only in the Bad Lands.
The bison, although now nearly extinct, formerly roamed over nearly the entire region between the Appalachian and the Rocky Mountains.
The herds of bison, antelope and elk that once roamed the prairies have vanished, but a few mountain sheep still graze on the grass-covered mesas in inaccessible portions of the Bad Lands.