Yellowstone National Park was established on March 1, 1872 by an act passed by the Congress of the United States of America. It is a mountainous area mostly in the northwestern corner of Wyoming, with small sections extending into Montana and Idaho. The area set aside as a National Park is 3,471.51 square miles. It provides within its boundaries environmental conditions which make it possible for many of the mammals representative of the Rocky Mountains to carry out their complete life cycle without fear of persecution by man.

The men that first conceived the idea of preserving the Yellowstone area as a great National Park were primarily concerned with the preservation of the natural wonders such as the geysers and hot spring phenomena, the canyon and waterfalls, and the lakes. In those days little thought was given to the need for preserving our wild animals. However, it soon became apparent that the wild animals, once thought to be unlimited in numbers, would have to have protection if they were going to be preserved for future generations. Yellowstone soon became known nearly as much for its wildlife as for its natural wonders.

The wild animals of Yellowstone National Park are widely distributed over the park area, some of them being restricted to limited areas due to the difference in elevation and the availability of the certain types of habitat which they require, while others range over a wider part of the park, especially during certain seasons of the year.

The higher mountain meadows are ideal summer ranges for the larger mammals. These animals would normally work down into the lower country outside of Yellowstone to the north for the winter. Since that area is now mostly under fence they have been forced to do the best they can up in the winter snows of the lower sections of the park. Bears and several of the smaller animals go into hibernation as soon as or even before the first snow squalls of winter appear so the long winter in the high country holds no terrors for them.

It is the policy of the National Park Service to present these animals to the visiting public in as near their natural environment as possible, each species being left to carry on its normal existence unassisted wherever possible. Unfortunately the lack of sufficient winter range within the park for unlimited numbers of animals has made it necessary that the numbers of bison, elk and antelope be controlled and management practices be put into effect in order to hold the number down to the carrying capacity of the range. So far these three species of animals have presented the only problem as far as overpopulation is concerned.

Predatory animals, especially the coyote, wolf and mountain lion were at one time controlled by hunting. The present policy is to let the predators carry on their own normal life as it is believed to be best for them and all other animals concerned and only in unusual circumstances will any control measures be carried out.