One of the biggest contributors to the ultimate decline of the buffalo due to unsustainable hunting was the fact that hunting bison became very easy and profitable around the mid-1800s. The peak of the hunts occurred in the middle of the 1870s, which is around when a new manufacturing process developed in Europe to turn buffalo hides into leather, which was then used to make leather belts for industrial machinery.
Before this process was developed and spread to America, bison hunters mostly killed for sport, food, or especially the bison's thick robes — their thick, furry winter coats. This meant that the worst of the hunting happened only during winter, when the robes were thickest. But when the new manufacturing method was created, harvesting thick robes became less important than getting simply any hides, since they would be made into leather anyway.
This is the economic aspect of the bison hunts that I will touch on in my essay. While it seems fairly neutral and disconnected from colonialist aspects of the hunt, I actually argue that it still feeds into those aspects. After all, while the hunts grew extremely rapidly from economic motivations, soon after, government and military officials saw an opportunity and took advantage of the buffalo decline as a strategy to pacify Indians. So in that way, the economic side of the hunt is just the initial launch point of an event that quickly grew into a colonialist effort.