Gray Ghosts, the Last Caribou in the Lower 48 States, Are 'Functionally Extinct'

The Selkirk herd had been disappearing for the last several years. In 2009, the herd, the southernmost in North America, had about 50 animals and was declining. Wildlife officials in Canada began a last-ditch effort to protect them by killing wolves, which occasionally preyed on the few caribou that remained. But the root cause of the extirpation of this herd and the decline of others in Canada is extensive industrial development in British Columbia, experts say.