Well, their propensity to flock together and strategy of predator satiation made them extremely vulnerable to commercial hunting. It also looks like they suffer

Well, their propensity to flock together and strategy of predator satiation made them extremely vulnerable to commercial hunting. It also looks like they suffered from the hunting equivalent of "panic logging": as the population collapsed, the commercial hunters reliant on them struggled to be the last hunter standing, rather than find another line of business before they went extinct. http://www.audubon.org/magazine/may-june-2014/why-passenger-pigeon-went-extinct http://www.audubon.org/magazine/may-june-2014/why-passenger-... The same thing nearly happened to the bison; there were less than 300 individuals left in 1900, mostly preserved as private property by a few individuals who wanted to save them from extinction. The Yosemite herd was an exception, 23 individuals than managed to hide out in Yellowstone. https://en.wikipedia.org/wiki/Bison_hunting#Resurgence_of_the_bison https://en.wikipedia.org/wiki/Bison_hunting#Resurgence_of_th...