Decimation of the Buffalo and Deer
Several factors, including disease brought on by stress, led to the decimation of the massive buffalo herds. The trade in buffalo hides, robes and tongues resulted in widespread hunting and waste. Governments encouraged the elimination of buffalo herds in order to starve Plains and Plateau peoples and make their removal to the reserves easier.
By the late 1800s, the vast herds of the Northern Plains had all but vanished. Many people believed that the buffalo spirit had become displeased with the way human beings had treated it. As a result, the buffalo decided to leave this world and return to the underworld and/or sky world, from where they had originally come.
The deer population was also greatly reduced in some areas of the Plateau. Increased demand from fur traders and improved methods of killing, the use of guns, led to overhunting. While less dramatic than the disappearance of the buffalo, the scarcity of deer and other large animals led to widespread starvation.