Blacktail deer (Odocoileus hemionus) resting in grass, Rocky Mountain National Park, Colorado, USA - Fotografía de stock

Two forms of black-tailed deer or blacktail deer that occupy coastal temperate rainforests in the Pacific Northwest are subspecies of the mule deer (Odocoileus hemionus). They have sometimes been treated as a species, but virtually all recent authorities maintain they are subspecies.