Sixty-one species of mammals have been recorded in Grand Teton National Park. This includes the gray wolf, which had been extirpated from the region by the early 1900s but migrated into the Grand Teton National Park from adjacent Yellowstone National Park after the species had been reintroduced there. The re-establishment of the wolves has ensured that every indigenous mammal species now exists in the park. In addition to gray wolves, another 17 species of carnivores reside within Grand Teton National Park including grizzlies and the more commonly seen American black bear. Relatively common sightings of coyote, river otter, marten and badger and occasional sightings of cougar, lynx and wolverine are reported annually. A number of rodent species exist including yellow-bellied marmot, least chipmunk, muskrat, beaver, Uinta ground squirrel, pika, snowshoe hare, porcupine, and six species of bats.