The main reason for the bison's near-demise, much like the actual demise of the Passenger Pigeon, was commercial hunting.
Bison skins were used for industrial machine belts, clothing such as robes, & rugs. There was a huge export trade to Europe of bison hides. Old West bison hunting was very often a big commercial enterprise, involving organized teams of one or two professional hunters, backed by a team of skinners, gun cleaners, cartridge reloaders, cooks, wranglers, blacksmiths, security guards, teamsters, & numerous horses & wagons. Men were even employed to recover & recast lead bullets taken from the carcasses. Many of these professional hunters, such as Buffalo Bill Cody, killed over a hundred animals at a single stand & many thousands in their career. One professional hunter killed over 20,000 by his own count. A good hide could bring $3 in Dodge City, Kansas, & a very good one (the heavy winter coat) could sell for $50 in an era when a laborer would be lucky to make a dollar a day.
The hunter would customarily locate the herd in the early morning, & station himself about 100 yards/meters from it, shooting the animals broadside through the lungs. Head shots were not preferred as the soft lead bullets would often flatten & fail to penetrate the skull, especially if mud was matted on the head of the animal. The bison would continue to drop until either the herd sensed danger & stampeded or perhaps a wounded animal attacked another, causing the herd to disperse. If done properly a large number of bison would be felled at one time. Following up were the skinners, who would drive a spike through the nose of each dead animal with a sledgehammer, hook up a horse team, & pull the hide from the carcass. The hides were dressed, prepared, & stacked on the wagons by other members of the organization.
For a decade after 1873, there were several hundred, perhaps over a thousand, such commercial hide hunting outfits harvesting bison at any one time, vastly exceeding the take by American Indians or individual meat hunters. The commercial take arguably was anywhere from 2,000 to 100,000 animals per day depending on the season, though there are no statistics available. It was said that the Big .50s were fired so much that hunters needed at least two rifles to let the barrels cool off; The Fireside Book of Guns reports they were sometimes quenched in the winter snow. Dodge City saw railroad cars sent East filled with stacked hides.
The building of the railroads through Colorado & Kansas split the bison herd in two parts, the southern herd & the northern herd. The last refuge of the southern herd was in the Texas Panhandle.
