Elk: Difference between revisions
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Recently, DNA evidence has supported the division of the ''Cervus elaphus'' ([[Red Deer]]) species into two and possibly three seperate species.<ref name="Ludt">{{cite web|last = Ludt | first = Christian J. |coauthors = Wolf Schroeder, Oswald Rottmann, and Ralph Kuehn| |
Recently, DNA evidence has supported the division of the ''Cervus elaphus'' ([[Red Deer]]) species into two and possibly three seperate species.<ref name="Ludt">{{cite web|last = Ludt | first = Christian J. |coauthors = Wolf Schroeder, Oswald Rottmann, and Ralph Kuehn| |
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title = Mitochondrial DNA phylogeography of red deer (Cervus elaphus)|work= Molecular Phylogenetics and Evolution 31 (2004) 1064–1083| publisher = Elsevier | url = http://www.wzw.tum.de/wildbio/paper/cerphyl.pdf#search=%22Barbary%20red%20deer%22| format= pdf|accessdate = 2006-10-06}}</ref> The previous species classification had over a dozen subspecies of related animals under the ''Cervus elephus'' species name, however the DNA evidence proves that elk are more closely related to central Asian subspecies and even the [[Sika Deer]] (''Cervus nippon'') than they are to the |
title = Mitochondrial DNA phylogeography of red deer (Cervus elaphus)|work= Molecular Phylogenetics and Evolution 31 (2004) 1064–1083| publisher = Elsevier | url = http://www.wzw.tum.de/wildbio/paper/cerphyl.pdf#search=%22Barbary%20red%20deer%22| format= pdf|accessdate = 2006-10-06}}</ref> The previous species classification had over a dozen subspecies of related animals under the ''Cervus elephus'' species name, however the DNA evidence proves that elk are more closely related to central Asian subspecies and even the [[Sika Deer]] (''Cervus nippon'') than they are to the red deer (''Cervus elaphus''). Though elk and red deer can produce fertile offspring under controlled circumstances, geographic isolation between the subspecies as well as modifications to mating behavior due to habitat and other influences, indicates that reproduction between the red deer and the elk in the wild would be far less likely to occur than would reproduction within their own subspecies.<ref name="Geist">{{cite book| last = Geist| first = Valerius| title = Deer of the World: Their Evolution, Behavior, and Ecology| publisher = Stackpole Books| date = 1998| location = Mechanicsburg, Pa| pages = | id =ISBN 0811704963}}</ref> |
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==Biology== |
==Biology== |
Revision as of 10:05, 6 November 2006
Cervus canadensis | |
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Species: | C. canadensis
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Cervus canadensis New species designate
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Elk (Cervus canadensis), are the second largest species of deer in the world, after the Moose (Alces alces). Elk are also referred to as "Wapiti", which is from the Native American word waapiti, or "white rump" used by the Shawnee. Elk are widely distributed across North America and far eastern Asia, and have been transplanted to other counties such as New Zealand and Argentina. Elk are not to be confused with the European animal also known as the Elk, which is the Moose of North America. Early European explorers to North America, that had seen smaller Red Deer in Europe, believed that the North American subspecies looked like an elk, which is the common word in Europe for what North Americans call a moose. The renaming has become part of the common vocabulary of North Americans.
Recently, DNA evidence has supported the division of the Cervus elaphus (Red Deer) species into two and possibly three seperate species.[1] The previous species classification had over a dozen subspecies of related animals under the Cervus elephus species name, however the DNA evidence proves that elk are more closely related to central Asian subspecies and even the Sika Deer (Cervus nippon) than they are to the red deer (Cervus elaphus). Though elk and red deer can produce fertile offspring under controlled circumstances, geographic isolation between the subspecies as well as modifications to mating behavior due to habitat and other influences, indicates that reproduction between the red deer and the elk in the wild would be far less likely to occur than would reproduction within their own subspecies.[2]
Biology
Appearance
The Red Deer is a large ungulate (hoofed animal) and is a ruminant, eating their food in two stages and having an even number of toes on each hoof, similar to camels, goats and cattle. The largest od the elk subspecies is the Roosevelt Elk (Cervus elaphus roosevelti) found west of the Cascade Range in the U.S. states of California, Oregon and Washington. The Roosevelt Elk males have also been transplanted into sections of Alaska, where they have been recorded as weighing up to 591 kilograms (1,300 lbs).[3]
At birth, the newborn elk calf weighs 35 pounds (16 kg). After a few years, elk cows average 500 pounds (225 kg), stand 4-1/2 feet (1.3 m) at the shoulder, and are 6-1/2 feet (2 m) from nose to tail. Bulls are more than 25% larger than cows at maturity, weighing in at an average of 700 pounds (315 kg), stand 5 feet (1.5 m) at the shoulder and are 8 feet (2.47nbsp;m) in length.[4]
Cervus elaphus roosevelti - Roosevelt Elk
Cervus elaphus nannodes - Tule Elk
Cervus elaphus nelsoni - Rocky Mountain Elk
Cervus elaphus manitobensis - Manitoban Elk
Only the males have antlers which start growing in the spring and are shed each year, usually at the end of winter. The largest antlers may be as much as 1.2 meters (4 ft) long and weigh 18 kilograms (40 lbs).[5] Antlers are made of bone which can grow at a rate of 2.5 centimeters (1 inch) a day and a soft covering known as velvet helps to protect newly forming antlers in the spring. Adult Red Deer may have 6 or more tines (finger-like extensions) on each antler, however the number of tines has little to do with the age or maturity of a particular specimen. All elk have a 6 prong plan (6 tines on each anter).[2] The antlers are testosterone driven and as their testosterone levels drop in the fall, the velvet is shed and the antlers stop growing.[6]
During the fall, all elk grow a thicker coat of hair which helps to insulate them during the winter. By the time summer begins, 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. Elk also have different coloration based on the seasons and types of habitats, with grey or lighter coloration prevelent in the winter and a more reddish and darker coat in the summer.[7]
Behavior
Adult elk usually stay in single-sex groups for most of the year. During the mating ritual, called the rut, mature stags compete for the attentions of the hinds and will then try to defend hinds that they attract. Rival stags challenge opponents by bellowing and walking in parallel. This allows combatants to assess each other's antlers, body size and fighting prowess. If neither stag backs down a clash of antlers can occur, and stags sometimes sustain serious injuries.[8]
Dominant stags follow groups of hinds during the rut, from August into early winter. The bulls may have as many as 20 females to keep from other less attractive males.[9] Only mature stags hold harems (groups of hinds) and breeding success peaks at about 8 years of age. Bulls 2-4 years old rarely hold harems and spend most of the rut on the periphery of larger harems, as do stags over 11 years old. Young and old bulls that do acquire a harem hold it later in the breeding season than those stags in their prime. Harem holding bulls rarely feed and lose up to 20% of their body weight. Bulls that enter the rut in poor condition are less likely to make it through to the peak conception period.[8]
Male elk have distinctive "bugling" which can be heard for miles, and is used to keep his harem of females together. Bugling is often associated with an adaptation to open environments such as parklands, meadows, and savannas where sound can resonate from afar. The females are initially attracted to those males that both bugle most often and have the loudest bugle call. Males also use the bugle call when competing with other males for females during the rut, and along with other forms of posturing and antler fights, is a method used by the males to establish dominance.[10] Bugling is most common during the early dawn and late evening.
Breeding, gestation and lifespan
Elk mating patterns usually involve a dozen of more mating attempts before the first successful one. There may be several more matings before the bull will seek out another mate in his harem. Females in their second autumn can produce one and very rarely two offspring per year. The gestation period is 240 and 262 days and the offspring weigh between 15 and 16 kilograms (33 to 35 lbs). After two weeks, calves are able to join the herd and are fully weaned after two months.[11] Female offspring outnumber male offspring more than two to one and all elk calves are born spotted, as is common with many deer species, and lose their spots by the end of summer. The offspring will remain with their mothers for almost one full year, leaving around the time that the next season offspring are produced.[10] The gestation period is the same for all subspecies.
Elk live up to over 20 years in captivity and average 10 to 13 years in the wild, though some subspecies that have less predation pressure average 15 years.[12]
DNA studies on Red Deer subspecies
Biologists have until recently stated that Red Deer and Elk are the same species, namely Cervus elaphus, based on fertile hybrids that have been produced under captive conditions. Animal behavior is generally different in captivity than in the wild, and the assumption that the same results would happen in the wild as in captivity is not necessarily the best test methodology to determine speciation. Recent DNA studies conducted on hundreds of samples from Red Deer and Elk subspecies determined that there are two distinct species and divides them into the Elk/Wapiti (Cervus canadensis) and Red Deer (Cervus elaphus). Additionally, the DNA evidence supports that there are three subspecies of elk. Another one or two "primordial subspecies" may exist in central Asia, according to the study. [1]
Elk are believed to number over 1 million in North America and maybe half that many more in east Asia and as transplants in places like New Zealand, Argentia and Chile. The International Union for Conservation of Nature and Natural Resources has identified the Alashan Wapiti subspecies of Elk as being without enough data to render a verdict on the possiblility of whether the subspecies is endangered or not.[13]
Protection from predators
Male Elk retain their antlers for more than half the year and are more gregarious and less likely to group with other males when they have antlers. The antlers provide self defense as does a strong front-leg kicking action which is performed by both sexes when attacked. Once the antlers are shed, stags tend to form bachelor groups which allow them to cooperatively work together. Herds tend to have one or more members watching for potential danger while the remaining members eat and rest.[10]
After the rut, females form large herds of up to 50 individuals. The newborn calves are kept close to the hinds by a series of vocalizations between the two, and larger nurseries have an ongoing and constant chatter during the daytime hours. When approached by predators, the largest and most robust females may make a stand, using their front legs to kick at their attackers. Guttural grunts and posturing is used with all but the most determined of predators with great effectiveness. Aside from man, Wolf and coyote packs and the solitary Mountain lion, are the most dangerous of predators that most Red Deer encounter. Occasionally, the Brown bear, grizzly and the black bear will predate on elk as well.[10] Major predators in Asia include wolves, dholes, brown bears, Siberian tigers, and snow leopards. Eurasian Lynx and wild boars sometimes prey on the calves.
Distribution and habitat
Cervus genus ancestors of elk first appear in fossil records 12 million years ago during the Pliocene in Eurasia but do not appear in the North American fossil records until about 12,000 years ago, when they crossed the Bering land bridge.[14][15] An extinct species, known as the Irish Elk (Megaloceros) was not an elk at all, but simply the largest member of the deer family known from the fossil record.[16]
Over time, several groups of elk in North America became isolated from one another, forming distinct behavioral characteristics to suit the environment. Over predation of many elk brought the eastern variety of elk (Cervus elaphus canadensis) to extinction, and the Merriam's elk (Cervus elaphus merriami) of the southwestern U.S. and Mexico eventually succumbed to extinction around 1900.[17] In the early 1900s concerned sportsmen foresaw the eventual demise of many game animals and sought, and implemented, hunting seasons and limits, which saved many species which would have otherwise perished.
Elk are one of the largest game animals found in Asia and North America. They live in open forest and near forest boundaries in similar environment as other deer species such as the Mule and White-tailed Deers. In mountainous regions, they are known to inhabit high elevations during the summer, and in winter they gather at lower altitudes. The highly adaptable elk also inhabit arid regions in North American such as the Great Basin.
Elk are found throughout North America, especially in the Rocky Mountain region. Reintroduced elk in Appalachian region of the eastern United States where the now extinct subspecies Eastern elk Cervus elaphus canadensis once lived, have dispersed from Kentucky, North Carolina and Tennessee, into the neighboring states of Virginia and West Virginia, and these herds appear to be growing steadily in population.[18] As of 1989, population figures for Rocky Mountain elk alone were 782,500 and estimated numbers for all North American subspecies exceeded 1 million.[19]
Elk were introduced to Argentina in the early 20th century and are considered a nuisance animal there for the most part. The highly adaptable elk have encroached on habitat in Argentina, and use up food supplies that normally would be consumed by the indigenious Huemul deer (Hippocamelus bisulcus) and other herbivours.[20] In New Zealand, and to a much lesser degree in Australia, introduced Red Deer and Elk have adapted well, and hunting is extensive. In Argentina, where the elk has had a potential negative impact on native animal species, the International Union for Conservation of Nature and Natural Resources has labelled the animal as one of the worlds 100 worst invaders.[21]
Migration
Elk migration in the lower 48 states of the United States has been, for many decades, the largest migration of mammals since the near extermination of the Bison in the late 1800s. What is known as the Yellowstone herd numbers up to 10,000 individuals. Each fall, the elk in Montana and Idaho as well as northern Wyoming begin a migration that has been a seasonal occurrence for thousands of years. Prior to the establishment of the town of Jackson, Wyoming, the herd would migrate south through Yellowstone and Grand Teton National Parks as well as surrounding National Forests through where the town of Jackson now resides and into grasslands more than 160 kilometers (100 miles) to the south. However, since the town now impedes this natural migration route, most of the herd spends the winter at a much higher altitude than they historically did. Just outside the town limits, the National Elk Refuge was established, and conservationists there ensure the herd is well fed during the harsh winters.[22]
Health issues
Brainworm (Parelaphostrongylus tenuis) is a parasitic nematode that has been known to affect the spinal cord and brain tissue of elk, leading to death. The nematode has a carrier in the White-tailed Deer, in which it usually has no ill effect, but is deposited in snails which are inadvertently consumed during grazing.[23] Chronic Wasting Disease effects the brain tissue in elk, has been detected throughout the range in North America. First documented in the late 1960s in Mule Deer, the elk effected have been on game farms and in the wild in a number of regions. Elk that have contracted the disease begin to show weight loss, increased watering needs, disorientation, listlessness, and at an advanced stage leads to death. The disease is similar to, but not the same as Mad Cow Disease and no side effects to humans have been documented, nor has the disease been demonstrated to pose a threat to domesticated cattle.[24] Brucellosis is another disease that occasionally affect Red Deer in North America, but is much more common in Bison.
Red Deer in folklore
The Elk is depicted in pictographs and petroglyphs throughout North America.[25]
Elk products
Elk are held in captivity for a variety of reasons. In some circumstances, hunting interests set aside game farms, where hunters can pay a fee and be essentially guaranteed a chance to shoot an elk, as they are fenced in and have less opportunity to escape. Elk meat is not generally harvested for human consumption on a large scale, though specialty restaurants seasonally offer elk meat which is widely considered to be both flavorful and nutritious. Elk is higher in protein and lower in fat than either beef or chicken.[26] In some countries in central Asia, elk is still hunted as a primary source of meat.
The elk can produce 22 to 25 pounds (10 to 11 kg) of antler velvet annually and on ranches in the United States, Canada and New Zealand, this velvet is collected and sold to markets in east Asia, where it is used for holistic medicines, with South Korea being the primary consumer. The antlers themselves are also believed by east Asians to have medicinal purposes and is often ground up and used in small quanities. The antlers are also highly sought after worldwide for decorative purposes and have been used for artwork, furniture and other novelty items.
External links
References cited
- ^ a b Ludt, Christian J. "Mitochondrial DNA phylogeography of red deer (Cervus elaphus)" (pdf). Molecular Phylogenetics and Evolution 31 (2004) 1064–1083. Elsevier. Retrieved 2006-10-06.
{{cite web}}
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suggested) (help) - ^ a b Geist, Valerius (1998). Deer of the World: Their Evolution, Behavior, and Ecology. Mechanicsburg, Pa: Stackpole Books. ISBN 0811704963.
- ^ Eide, Sterling. "Roosevelt Elk". Alaska Department of Fish and Game. Retrieved 2006-10-03.
- ^ "Fast Facts about Elk". Rocky Mountain Elk Foundation. Retrieved 2006-11=06.
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(help) - ^ "What Is An Elk?". Rocky Mountain Elk Foundation. Retrieved 2006-10-03.
- ^ "Friends of the Prairie Learning Center". U.S. Fish and Wildlife Service. Retrieved 2006-10-06.
- ^ Pisarowicz, Jim. "American Elk - Cervus elephus". National Park Service. Retrieved 2006-10-10.
- ^ a b Walker, Mark. "The Red Deer". World Deer Website. Retrieved 2006-10-03.
- ^ "Elk (Cervus elaphus)". South Dakota Department of Game, Fish and Parks. Retrieved 2006-10-03.
- ^ a b c d Cite error: The named reference
Thomas
was invoked but never defined (see the help page). - ^ "Cervus elaphus". Animal Diversity Web. University of Michigan, Museum of Zoology. Retrieved 2006-10-04.
- ^ "Elk". Great Smoky Mountains. National Park Service. Retrieved 2006-10-04.
- ^ "Cervus elaphus". IUCN Red List of Threatened Species. International Union for Conservation of Nature and Natural Resources. Retrieved 2006-10-14.
{{cite web}}
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(help) - ^ "The Ecology of Red Deer". Deer-UK. Retrieved 2006-10-02.
- ^ Hansen, Michael. "Ohio Elk". Ohio Geological Survey. Retrieved 2006-10-03.
- ^ "The Case of the Irish Elk". University of California, Berkeley. Retrieved 2006-10-03.
- ^ Allen, Craig. "Elk Reintroductions". U.S. Geological Survey. Retrieved 2006-10-03.
- ^ Ledford, David. "Seeing the Southern Appalachians with 2030 Vision". Rocky Mountain Elk Foundation. Retrieved 2006-10-02.
- ^ Peek, James. "North American Elk". U.S. Geological Survey. Retrieved 2006-10-09.
- ^ "Diet of Huemul deer ( Hippocamelus bisulcus ) in Nahuel Huapi National Park, Argentina". Taylor and Francis Ltd. Retrieved 2006-10-14.
- ^ Flueck, Werner. "Cervus elaphus (mammal)". Global Invasive Species Database. International Union for Conservation of Nature and Natural Resources. Retrieved 2006-10-14.
- ^ "National Elk Refuge". U.S. Fish and Wildlife Service. Retrieved 2006-10-04.
- ^ Fergus, Chuck. "Elk". Pennsylvania Game Commission. Retrieved 2006-10-03.
- ^ "Chronic Wasting Disease". Rocky Mountain Elk Foundation. Retrieved 2006-10-04.
- ^ "Elk In History". Rocky Mountain Elk Foundation. Retrieved 2006-10-09.
- ^ "Elk Meat Nutritional Information". Wapiti.net. Retrieved 2006-10-10.
Category:Deer Category:Mammals of Asia Category:Wildlife of North America