The passenger pigeon was hunted in Northern Michigan as a source of food, but by the 1870s, a combination of increased population and economic scarcity led to over-hunting and eventual extinction. The massive flocks of passenger pigeons stopped darkening the skies of Northern Michigan, especially after the last large scale nestings and subsequent slaughters of millions of birds in 1874 and 1878. By this time, large nestings only took place in the north, around the Great Lakes. The last large nesting was in Petoskey, Michigan, in 1878 (following one in Pennsylvania a few days earlier), where 50,000 birds were killed each day for nearly five months. The surviving adults attempted a second nesting at new sites, but were killed by professional hunters before they had a chance to raise any young. Scattered nestings were reported into the 1880s, but the birds were now weary, and commonly abandoned their nests if persecuted.