Population
Up to the 18th century it is estimated, bison had population of around 60’000’000. Natives respected the nature and took only what they needed, even when they had horses. The greed of the white man resulted in a drastic reduction of bison population over few decades. The modern fire arms allowed them to destroy hugh numbers.
Building the railway resulted need of food for workers and with opening the Central Pacific Rail Road hunting became sport. The so called hunters were able to kill 50-100 bisons a day. One of the most famous bison killer was William. F .Cody , known as Buffalo Bill. (American hero).
From 1872 until 1874, more than one million bisons were killed every year. The Railway cut the bison territory into North and South herds.