Caribou in Ontario? Yeah, maybe in Moose Factory. Nope, right on the north shore of Lake Superior, a half-day's ride from Michigan. On islands that were formed by extraterrestrial forces, no less.
Backpacker Magazine recently featured the native caribou population on Lake Superior's Slate Islands. The big ungulates crossed over to the islands on icy Lake Superior years ago. The 200 or so reindeer there now have no natural predators and enjoy a peaceful existence in a provincial park.
The Slate Islands were formed by a meteorite likely 450 million years ago. The islands are the central uplift from the collision. Impact may have taken place during the Orodovician period. Favorite Orodovician fauna: the arandaspis, a type of jawless fish.