In Oregon, 136 mammals (excluding whales, dolphins, and porpoises) have been documented, including nine introduced species. Four species, the Baird's Shrew, the Pacific Shrew, the Camas Pocket Gopher, and the Red Tree Vole, are only found in Oregon.
Many of the well-known large carnivores such as the grizzly bear, gray wolf, lynx, and wolverine have either been extirpated or occur in very low numbers. The majority of the mammalian fauna in Oregon is small (< 1 kg), furtive, primarily nocturnal and is much less well known then the larger, charismatic species. Please see the American Society of Mammalogists list, Mammals of Oregon.