1896  The caribou .. . has many enemies besides the Indian, and none more implacable than the arctic wolves, which in summer are constantly on its tracks.
1940  Arctic wolves are not invariably pure creamy white, but are often of darkish grizzled pelage, especially over the dorsal tract.
1963  I was peering straight into the amber gaze of a fully grown arctic wolf, who probably weighed more than I did. . . .