The California mule deer (''Odocoileus hemionus californicus'') is a

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

mule deer The mule deer (''Odocoileus hemionus'') is a deer indigenous to western North America; it is named for its ears, which are large like those of the mule. Two subspecies of mule deer are grouped into the black-tailed deer. Unlike the related whit ...

whose range covers much of the state of

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

Anatomy

One of the principal means of distinguishing the closely related

black-tailed deer Two forms of black-tailed deer or blacktail deer that occupy coastal woodlands in the Pacific Northwest of North America are subspecies of the mule deer (''Odocoileus hemionus''). They have sometimes been treated as a species, but virtually all r ...

and

white-tailed deer The white-tailed deer (''Odocoileus virginianus''), also known as the whitetail or Virginia deer, is a medium-sized deer native to North America, Central America, and South America as far south as Peru and Bolivia. It has also been introduced t ...

is the growth habit of the buck's

antler Antlers are extensions of an animal's skull found in members of the Cervidae (deer) family. Antlers are a single structure composed of bone, cartilage, fibrous tissue, skin, nerves, and blood vessels. They are generally found only on male ...

s. In the case of the Black Tail and California mule deer, the antlers fork in an upward growth, whereas the other species' antlers grow in a forward direction.

Distribution

This subspecies, ''O. h. californicus'', is widespread throughout northern and central California in the

California coastal prairie California coastal prairie, also known as northern coastal grassland, is a grassland plant community of California and Oregon in the temperate grasslands, savannas, and shrublands biome. It is found along the Pacific Coast, from as far south as L ...

, as well as inner coastal ranges and interior mountains, especially the

Sierra Nevada The Sierra Nevada () is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily ...

. This deer is much less frequently found on the floor of the interior

valley A valley is an elongated low area often running between Hill, hills or Mountain, mountains, which will typically contain a river or stream running from one end to the other. Most valleys are formed by erosion of the land surface by rivers ...

s, and then mostly frequently in

riparian zone A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the terrestrial biomes of the Earth. Plant habitats and communities along the river margins and banks ar ...

Habitat

Generally, the California mule deer has a preference for hill terrain, especially an

oak An oak is a tree or shrub in the genus ''Quercus'' (; Latin "oak tree") of the beech family, Fagaceae. There are approximately 500 extant species of oaks. The common name "oak" also appears in the names of species in related genera, notably ''L ...

woodland A woodland () is, in the broad sense, land covered with trees, or in a narrow sense, synonymous with wood (or in the U.S., the ''plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunlight and limited shade (see ...

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

. It is a browser and typically takes over 90% of its diet from shrubs and leaves and the balance from grasses.

Diet and behavior

California mule deer usually browse close to lakes or streams providing their water. From that water source, they may roam 1-2 mi, and typically make their beds in grassy areas beneath trees within such a one-mile radius from both water and forage. Repeatedly used beds often are scratched to a nearly level surface, about 2 m in diameter. Less regularly used bedding areas are seen as flattened grass. On hot summer days, California mule deer often seek shade and rest in the midday. In summer, California mule deer mainly browse on leaves of small trees, shrubs, and herbaceous plants, but also consume many types of

berries A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit, although many pips or seeds may be present. Common examples are strawberries, raspb ...

(including

blackberry The blackberry is an edible fruit produced by many species in the genus ''Rubus'' in the family Rosaceae, hybrids among these species within the subgenus ''Rubus'', and hybrids between the subgenera ''Rubus'' and ''Idaeobatus''. The taxonomy of ...

huckleberry Huckleberry is a name used in North America for several plants in the family Ericaceae, in two closely related genera: ''Vaccinium'' and ''Gaylussacia''. The huckleberry is the state fruit of Idaho. Nomenclature The name 'huckleberry' is a Nort ...

salal ''Gaultheria shallon'' is an evergreen shrub in the heather family (Ericaceae), native to western North America. In English, it is known as salal, shallon, or (mainly in Britain) gaultheria. Description ''Gaultheria shallon'' is tall, spra ...

, and

thimbleberry ''Rubus parviflorus'', commonly called thimbleberry, (also known as redcaps) is a species of ''Rubus'' native to northern temperate regions of North America. The plant has large hairy leaves and no thorns. It bears edible red fruit similar in a ...

). In winter, they may expand their forage to

conifer Conifers are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single ...

s (particularly twigs of Douglas fir),

aspen Aspen is a common name for certain tree species; some, but not all, are classified by botanists in the section ''Populus'', of the ''Populus'' genus. Species These species are called aspens: *'' Populus adenopoda'' – Chinese aspen (China ...

willow Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist s ...

dogwood ''Cornus'' is a genus of about 30–60 species of woody plants in the family Cornaceae, commonly known as dogwoods, which can generally be distinguished by their blossoms, berries, and distinctive bark. Most are deciduous trees or shrub ...

juniper Junipers are coniferous trees and shrubs in the genus ''Juniperus'' () of the cypress family Cupressaceae. Depending on the taxonomy, between 50 and 67 species of junipers are widely distributed throughout the Northern Hemisphere, from the Arcti ...

, and

sage Sage or SAGE may refer to: Plants * ''Salvia officinalis'', common sage, a small evergreen subshrub used as a culinary herb ** Lamiaceae, a family of flowering plants commonly known as the mint or deadnettle or sage family ** ''Salvia'', a large ...

. Year-round, they feed on

acorn The acorn, or oaknut, is the nut of the oaks and their close relatives (genera ''Quercus'' and '' Lithocarpus'', in the family Fagaceae). It usually contains one seed (occasionally two seeds), enclosed in a tough, leathery shell, and borne ...

s; grasses are a secondary food source. Where humans have encroached on historic deer habitat by suburban development or orchards, California mule deer diversify their diet with

garden A garden is a planned space, usually outdoors, set aside for the cultivation, display, and enjoyment of plants and other forms of nature. The single feature identifying even the wildest wild garden is ''control''. The garden can incorporate both ...

plant material, tree fruit, and occasionally, pet food. Fawns and does tend to forage together in familial groupings, while bucks tend to travel singly or with other bucks. California mule deer browse most actively near dawn and dusk, but also forage at night in open

agricultural Agriculture or farming is the practice of cultivating Plant, plants and livestock. Agriculture was the key development in the rise of Sedentism, sedentary human civilization, whereby farming of Domestication, domesticated species created food ...

areas or when experiencing

hunting Hunting is the human activity, human practice of seeking, pursuing, capturing, or killing wildlife or feral animals. The most common reasons for humans to hunt are to harvest food (i.e. meat) and useful animal products (fur/hide (skin), hide, ...

pressure.

Breeding

Rutting season occurs in autumn when the does come into

estrus The estrous cycle (, originally ) is the set of recurring physiological changes that are induced by reproductive hormones in most mammalian therian females. Estrous cycles start after sexual maturity in females and are interrupted by anestrous p ...

for a period lasting only several days. Males exhibit

aggressive Aggression is overt or covert, often harmful, social interaction with the intention of inflicting damage or other harm upon another individual; although it can be channeled into creative and practical outlets for some. It may occur either reacti ...

behavior in competing for mates. Does begin estrus again if they do not become pregnant. The

gestation Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregna ...

period is about 200 days, with fawns arriving in the spring; the young remain with mothers throughout the summer and are weaned in the autumn. The buck's antlers fall off in the winter, and commence growing once more in spring in anticipation of next autumn's rut. Buck Fall 2005

Human interactions

Since prehistoric times, the Native American

indigenous peoples of California The indigenous peoples of California (known as Native Californians) are the indigenous inhabitants who have lived or currently live in the geographic area within the current boundaries of California before and after the arrival of Europeans. ...

are known to have hunted California mule deer. Thus, since about 12,000 BCE, Gage suggests that human

population Population typically refers to the number of people in a single area, whether it be a city or town, region, country, continent, or the world. Governments typically quantify the size of the resident population within their jurisdiction using a ...

s have served as a control to the numbers of California mule deer. In the modern era, since European colonists and Euro-Americans settled in California, hunting pressure intensified as the human population expanded and hunting became an activity not just associated with food supply. In addition, human population growth (through urban development) in California has consumed large amounts of natural habitat of the California mule deer starting in the late 19th century and continuing through the present.

References

External links

U.S. Forest Service treatment — ''Odocoileus hemionus'' (Mule Deer)
— including subspecies ''californicus'' {{Taxonbar, from=Q5021281 Deer Mammals of the United States Endemic fauna of California Fauna of the Sierra Nevada (United States) Fauna of the California chaparral and woodlands Natural history of the California Coast Ranges Natural history of the Santa Monica Mountains Pre-Columbian California cuisine Fauna without expected TNC conservation status