Pen in Hand: California Mule Deer or Black-tailed Deer? Identifying the deer in our mountains.

Mule Deer are the genus Odocoileus and the species hemionus. There are different subspecies of them, so scientists tack on a third name. In the case of California Mule Deer, that third name is californicus.

There are currently 10 different recognized subspecies of Mule Deer, including Rocky Mountain Mule Deer, whose bucks occasionally exceed 400 pounds. The Mule Deer in our area don't reach that size.