Blacktail deer may be Olympic National Park's most graceful mammal. They are much smaller than Roosevelt elk, and may be seen just about anywhere within Olympic National Park, from subalpine forests and meadowlands down to river valleys. Blacktail deer are considered a subspecies of mule deer, which are common throughout much of the Western US. They are also closely related to the white-tailed deer, well-known throughout the eastern and Midwestern U.S. ~ Olympic National Park Website