| Elk Temporal range: 2.5–0 Ma Early Pleistocene – Recent | |
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| Elk (male) | |
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| Elk (female) | |
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| Former (light green) and current (dark green) native ranges of Cervus canadensis | |
The elk or wapiti (Cervus canadensis) is one of the largest species within the deer family, Cervidae, in the world, and one of the largest land mammals in North America and Eastern Asia. This animal should not be confused with the still larger moose (Alces alces) to which the name "elk" applies in British English and in reference to populations in Eurasia.
Elk range in forest and forest-edge habitat, feeding on grasses, plants, leaves, and bark. Male elk have large antlers which are shed each year. Males also engage in ritualized mating behaviors during the rut, including posturing, antler wrestling (sparring), and bugling, a loud series of vocalizations that establishes dominance over other males and attracts females.
Although they are native to North America and eastern Asia, they have adapted well to countries in which they have been introduced, including Argentina and New Zealand. Their great adaptability may threaten endemic species and ecosystems into which they have been introduced.
Elk are susceptible to a number of infectious diseases, some of which can be transmitted to livestock. Efforts to eliminate infectious diseases from elk populations, largely by vaccination, have had mixed success.
Some cultures revere the elk as a spiritual force. In parts of Asia, antlers and their velvet are used in traditional medicines. Elk are hunted as a game species. The meat is leaner and higher in protein than beef or chicken.[3]
It was long believed to be a subspecies of the European red deer (Cervus elaphus), but evidence from a number of mitochondrial DNA genetic studies beginning in 1998 show that the two are distinct species.[4][5][6][7] Key morphological differences that distinguish C. canadensisfrom C. elaphus are the former's wider rump patch and paler-hued antlers. ....
The elk is a large animal of the ungulate order Artiodactyla, possessing an even number of toes on each foot, similar to those of camels, goats and cattle. It is a ruminant species, with a four-chambered stomach, and feeds on grasses, plants, leaves and bark. During the summer, elk eat almost constantly, consuming between 4 and 7 kilograms (8.8 and 15.4 lb) of vegetation daily.[22] In North America, males are called bulls, and females are called cows. In Asia, stag and hind, respectively, are sometimes used instead.
Elk are more than twice as heavy as mule deer and have a more reddish hue to their hair coloring, as well as large, buff-colored rump patches and smaller tails. Moose are larger and darker than elk; bulls have distinctively different antlers. Elk gather in herds, while moose are solitary. Elk cows average 225 to 241 kg (496 to 531 lb), stand 1.3 m (4.3 ft) at the shoulder, and are 2.1 m (6.9 ft) from nose to tail. Bulls are some 40% larger than cows at maturity, weighing an average of 320 to 331 kg (705 to 730 lb), standing 1.5 m (4.9 ft) at the shoulder and averaging 2.45 m (8.0 ft) in length.[23][24] The largest of the subspecies is the Roosevelt elk (C. c. roosevelti), found west of the Cascade Range in the U.S. states of California, Oregon and Washington, and in the Canadian province of British Columbia. Roosevelt elk have been reintroduced into Alaska, where the largest males are estimated to weigh up to 600 kg (1,300 lb).[25] More typically, male Roosevelt elks weigh around 300 to 544 kg (661 to 1,199 lb), while females weigh 260 to 285 kg (573 to 628 lb).[26][27] The smallest-bodied race is the tule elk (C. c. nannodes), which weighs from 170 to 250 kg (370 to 550 lb) in both sexes.[26]
Only the males have antlers, which start growing in the spring and are shed each winter. The largest antlers may be 1.2 metres (3.9 ft) long and weigh 18 kilograms (40 lb).[28] Antlers are made of bone which can grow at a rate of 2.5 centimetres (0.98 in) per day. While actively growing, the antlers are covered with and protected by a soft layer of highly vascularised skin known as velvet. The velvet is shed in the summer when the antlers have fully developed. Bull elk may have eight or more tines on each antler; however, the number of tines has little to do with the age or maturity of a particular animal. The Siberian and North American elk carry the largest antlers while the Altai wapiti have the smallest.[15] The formation and retention of antlers is testosterone-driven.[29] After the breeding season in late fall, the level of pheromones released during estrus declines in the environment and the testosterone levels of males drop as a consequence. This drop in testosterone leads to the shedding of antlers, usually in the early winter.
During the fall, elk grow a thicker coat of hair, which helps to insulate them during the winter. Males, females and calves of Siberian and North American elk all grow thin neck manes; female and young Manchurian and Alaskan wapitis do not.[20] By early summer, the heavy winter coat has been shed, and elk are known to rub against trees and other objects to help remove hair from their bodies. All elk have small and clearly defined rump patches with short tails. They have different coloration based on the seasons and types of habitats, with gray or lighter coloration prevalent in the winter and a more reddish, darker coat in the summer. Subspecies living in arid climates tend to have lighter colored coats than do those living in forests.[30] Most have lighter yellow-brown to orange-brown coats in contrast to dark brown hair on the head, neck, and legs during the summer. Forest-adapted Manchurian and Alaskan wapitis have darker reddish-brown coats with less contrast between the body coat and the rest of the body during the summer months.[15] Calves are born spotted, as is common with many deer species, and they lose their spots by the end of summer. Adult Manchurian wapiti may retain a few orange spots on the back of their summer coats until they are older. This characteristic has also been observed in the forest-adapted European red deer.[15]
Behavior[edit]
Adult elk usually stay in single-sex groups for most of the year. During the mating period known as the rut, mature bulls compete for the attentions of the cow elk and will try to defend females in their harem. Rival bulls challenge opponents by bellowing and by paralleling each other, walking back and forth. This allows potential combatants to assess the other's antlers, body size and fighting prowess.[31] If neither bull backs down, they engage in antler wrestling, and bulls sometimes sustain serious injuries. Bulls also dig holes in the ground called wallows, in which they urinate and roll their body.[32] A male elk's urethra points upward so that urine is sprayed almost at a right angle to the penis.[33] The urine soaks into their hair and gives them a distinct smell which attracts cows.[32]
Dominant bulls follow groups of cows during the rut, from August into early winter. A bull will defend his harem of 20 cows or more from competing bulls and predators.[34] Only mature bulls have large harems and breeding success peaks at about eight years of age. Bulls between two and four years and over 11 years of age rarely have harems, and spend most of the rut on the periphery of larger harems. Young and old bulls that do acquire a harem hold it later in the breeding season than do bulls in their prime. A bull with a harem rarely feeds and he may lose up to 20 percent of his body weight. Bulls that enter the rut in poor condition are less likely to make it through to the peak conception period or have the strength to survive the rigors of the oncoming winter.[31]
Bulls have a loud vocalization consisting of screams known as bugling, which can be heard for miles. Bugling is often associated with an adaptation to open environments such as parklands, meadows, and savannas, where sound can travel great distances. Females are attracted to the males that bugle more often and have the loudest call.[35] Bugling is most common early and late in the day and is one of the most distinctive sounds in nature, akin to the howl of the gray wolf....
Distribution[edit]
Modern subspecies are descended from elk that once inhabited Beringia, a steppe region between Asia and North America that connected the two continents during the Pleistocene. Beringia provided a migratory route for numerous mammal species, including brown bear, camel, horse, caribou, and moose, as well as humans.[63] As the Pleistocene came to an end, ocean levels began to rise; elk migrated southwards into Asia and North America. In North America they adapted to almost all ecosystems except for tundra, true deserts, and the gulf coast of the U.S. The elk of southern Siberiaand central Asia were once more widespread but today are restricted to the mountain ranges west of Lake Baikal including the Sayan and Altai Mountains of Mongolia and the Tianshan region that borders Kyrgyzstan, Kazakhstan, and China's Xinjiang Province.[1] The habitat of Siberian elk in Asia is similar to that of the Rocky Mountain subspecies in North America.
Throughout their range, they live in forest and in forest edge habitat, similar to other deer species. In mountainous regions, they often dwell at higher elevations in summer, migrating down slope for winter. The highly adaptable elk also inhabit semi-deserts in North America, such as the Great Basin. Manchurian and Alashan wapiti are primarily forest dwellers and their smaller antler size is a likely adaptation to a forest environment.
Introductions[edit]
The Rocky Mountain elk subspecies has been reintroduced by hunter-conservation organizations in the Appalachian region of the eastern U.S., where the now extinct eastern elk once lived[64] After elk were reintroduced in the states of Kentucky, North Carolina and Tennessee, they migrated into the neighboring states of Virginia and West Virginia, and have established permanent populations there.[65] In 2017, a male elk, likely from the Smoky Mountainspopulation, was sighted in South Carolina for the first time in nearly 300 years.[66] Elk have also been reintroduced to a number of other states, including Pennsylvania,[67][68] Michigan, Wisconsin, Missouri [69] and Etolin and Afognak Islands in Alaska.[70]Reintroduction of the elk into Ontario began in the early 20th century, and is still ongoing due to the limited success.[71] As of 1989, population figures for the Rocky Mountain subspecies were 782,500, and estimated numbers for all North American subspecies exceeded 1 million.[72] Prior to the European colonization of North America, there were an estimated 10 million elk on the continent.[23]
Outside their native habitat, elk and other deer species, especially white tails, were introduced in areas that previously had few if any large native ungulates. Brought to these countries for hunting and ranching for meat, hides and antler velvet, they have proven highly adaptable and have often had an adverse impact on local ecosystems. Elk and red deer were introduced to Argentina in the early 20th century.[73] There they are now considered an invasive species, encroaching on Argentinian ecosystems where they compete for food with the indigenous Chilean huemul and other herbivores.[74] This negative impact on native animal species has led the IUCN to identify the elk as one of the world's 100 worst invaders.[75]
The introduction of deer to New Zealand began in the middle of the 19th century, and current populations are primarily European red deer, with only 15 percent being elk.[76] There is significant hybridization of elk with the more numerous red deer to the extent that pure elk may no longer exist in the wild in New Zealand. These deer have had an adverse impact on forest regeneration of some plant species, as they consume more palatable species which are replaced with those that are less favored by the elk. The long-term impact will be an alteration of the types of plants and trees found, and in other animal and plant species dependent upon them.[77] As in Chile and Argentina, the IUCN has declared that red deer and elk populations in New Zealand are an invasive species.[75]
Cultural references[edit]
Elk have played an important role in the cultural history of a number of peoples. Pictograms and petroglyphs of elk were carved into cliffs thousands of years ago by the Anasazi of the southwestern U.S. More recent Native American tribes, including the Kootenai, Cree, Blackfeet, Ojibwa and Pawnee, produced blankets and robes from elk hides. The elk was of particular importance to the Lakota, and played a spiritual role in their society.[78] At birth, Lakota males were given an elk's tooth to promote a long life since that was seen as the last part of dead elk to rot away. The elk was seen as having strong sexual potency and young Lakota males who had dreamed of elk would have an image of the mythical representation of the elk on their "courting coats" as a sign of sexual prowess. The Lakota believed that the mythical or spiritual elk, not the physical one, was the teacher of men and the embodiment of strength, sexual prowess and courage.
Neolithic petroglyphs from Asia depict antler-less female elk, which have been interpreted as symbolizing rebirth and sustenance. By the beginning of the Bronze Age, the elk is depicted less frequently in rock art, coinciding with a cultural transformation away from hunting.[79]
The Rocky Mountain elk is the official state animal for Utah.[80] An image of an elk and a moose appear on the state seal and flag of Michigan.[81] The Benevolent and Protective Order of Elks (B.P.O.E.) chose the elk as its namesake because a number of its attributes seemed appropriate for cultivation by members of the fraternity. A representation of the majestic head of the male, with its spreading antlers, was adopted as the first badge of the Order; and is still the most conspicuous element of its copyrighted fraternal emblem.[82] A prized possession of many members of the B.P.O.E. are jewel encrusted, gold mounted elk teeth – which are actually ivory.[83]
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