The bighorn sheep (Ovis canadensis) is one of the two species of wild sheep native to North America. It occupies southwestern Canada through to Mexico. Wild sheep originally arrived in America during the Pleistocene (750 000years ago) by crossing the Bering land bridge from Siberia into Alaska. Until the early 20th century bighorn sheep were common and widespread, but overhunting and diseases transmitted from domestic livestock have dramatically reduced their population since. Recent conservation efforts have only been effective to a limited extent, bighorn sheep are still absent of vast majority of their historical territories. Despite this sad state of affairs, hunting for bighorn sheep in Canada and the United States has only been heavily regulated rather than being banned altogether.
