Here is a really interesting article that is forthcomming in AER:
http://www.beijer.kva.se/PDF/41110606_Disc225.pdf
The evidence suggests that technological innovations in hide tanning combined with open access to bison led to their slaughter. The author draws some dramatic conclusions:
The Slaughter on the Plains tells us that putting development before environmental protection can be a risky proposition: in just a few short years, international markets and demand from high income countries can destroy resources that otherwise would have taken decades to deplete.
I thought it was worth passing around.