Natural History Story: The Mule Deer (Odocoileus hemionus)

The Mule Deer, Odocoileus hemionus, is a species that is indigenous to Western North America, from the tip of Baja California and Mexico all the way up to Southern Alaska. The species has also been introduced into Argentina. There are 10 confirmed subspecies including:
O. h. californicus (Caton, 1876) – California Mule Deer;
O. h. cerrosensis Merriam, 1898 – Cedros Island Deer;
O. h. columbianus (Richardson, 1829) – Columbian Black-tailed Deer;
O. h. crooki (Mearns, 1897) (eremicus Mearns and canus Merriam are synonyms), Heffelfinger (2000) considered O. h. eremicus as the correct name for Desert Mule Deer, because the specimen type of this subspecies is a hybrid of Mule Deer and White-tailed Deer;
O. h. fuliginatus Cowan, 1933 – Southern Mule Deer;
O. h. hemionus (Rafinesque, 1817) – Rocky Mountain Mule Deer;
O. h. inyoensis Cowan, 1933 (the validity is questionable) – Inyo Mule Deer;
O. h. peninsulae (Lydekker, 1898) – Peninsula Mule Deer;
O. h. sheldoni Goldman, 1939 – Tiburon Island Mule Deer;
O. h. sitkensis Merriam, 1898 – Sitka Black-tailed Deer.

The species, and its subspecies, are well adapted to a variety of ecosystems. The deer can be found in temperate forests, desert and semidesert, open range, grassland, field and scrub habitats as well as Mountainous areas. This adaptability has helped to keep populations stable by giving the species the ability to live in relocate when resources are sparse or conditions become unlivable. In harsh ecosystems the mule deer will have separate summer and winter ranges, with a migratory path connecting them. In the mild climates they will not migrate.

They live in small groups of three to five individuals.During he winter large groups often come together to feed. Interestingly, it has been noted that the female mule deer live close to where they are born while the males will migrate farther away to compete for mates. Their breeding season runs from October to November, and after this season the males lose their antlers and grow a new set. The newborn babies have spotted coats to keep them camouflaged from potential predators.

Luckily for the Mule Deer, the species is listed as a "least concerned" species under the IUCN red list. This means that the population of Mule Deer "is considered to be Least Concern in light of its adaptability to a wide range of habitats, large populations, occurrence in numerous protected areas, and populations seem to be relatively stable"(IUCN). This classification means that the IUCN does not consider the species in need of conservation efforts. However, some studies cited by the IUCN have shown declining populations in the United States, and some extinction of populations in areas of Mexico. Threats to their populations include the Chronic Wasting Disease, a transmissible spongiform encephalopathy, that has been found in some mule deer populations in the Rocky Mountains, predation by feral dogs, poaching, encroachment of grazing for livestock and human settlements, and "other" anthropogenic forces.

Due to these constraining forces on the mule deer populations, a group has formed called the Mule Deer Foundation. This organization began in Redding, California in 1988 and was incorporated as a 501(c)3 Wildlife Conservation Organization that year. Their mission is to "ensure the conservation of mule deer, black-tailed deer and their habitat.” The group started with banquet fund raising, and has grown to include its own Mule Deer Magazine!

Sources:
Wikipedia: http://en.wikipedia.org/wiki/Mule_deer
Mule Deer Foundation: http://eol.org/pages/328651/overview
IUCN Red List: http://www.iucnredlist.org/search

Posted on 22 April, 2014 22:58 by