Wolf
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| Grey Wolf Conservation status: Lower risk | ||||||||||||||
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| Canis lupus Linnaeus, 1758 |
The Grey Wolf (Canis lupus), also known colloquially as just the wolf, is a mammal of the Canidae family and the ancestor of the domestic dog. Wolves once had an almost worldwide distribution, but are now limited primarily to North America, Eurasia, and the Middle East. Their preference on habitat ranges among forests, tundra, taigas, plains and mountains. In the northern hemisphere, human encroachment on their habitat and persecution of the animals themselves have drastically reduced their range. The wolf is today frequently in the line of fire in conflicts between many different interests: tourism/industry, city/country, as well as conservation/exploitation.
As the wolf is an apex predator, the state of the wolf can frequently be seen as a state of the land where it lives. Wolves are still endangered after being hunted down in the 1600s.
Three other canid species are known as wolves: the Red Wolf, the Ethiopian Wolf, and the extinct Dire Wolf.
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Anatomy
Wolves weigh 23 to 60 kg (50 to 130 lb), and are about 1 to 1.5 m (40 to 60 in) long with the tail being roughly a third of their body length. The males are larger than the females. The coloration runs from grey to grey brown but can vary through the canine spectrum of white, reddish, brown and black. The coat usually lacks any clear patterns except for paintings around the eyes. In areas where the ground is snow covered white wolves are far more common. Very old wolves get a greyish tint in their coat.
The wolf anatomy differs on several points from the dog. Most obvious is a pre-caudal gland on the over side of the tail, close to the base, that is not present on dogs. The wolf usually has golden-yellow eyes, longer legs, larger paws and more pronounced jaws.
The body of the wolf is built for long distance running, with a rather thin chest and powerful back and leg muscles. Wolves can move over great distances and the wide paws make sure deep snow hampers them less than their prey.
A wolf often seems more massive than a dog of comparable weight due to the extra bulk of the coat. The coat is built up of two layers, with hard guard hairs to repel water and dirt and a thick woolly undercoat to keep it warm. The wolf changes coat two times a year, during spring and autumn. Females tend to have a thicker winter coat and keep it further into the spring than males.
The wolves and most larger dogs share the same tooth configuration: The upper jaw has 6 incisors, 2 canines, 8 premolars, and 4 molars. The bottom jaw has 6 incisors, 2 canines, 8 premolars, and 6 molars. The canines are by far most important, as they are used to catch and hold prey. One common reason for wolves to starve is tooth damage after being kicked by larger prey.
Wolves live 6–9 years average in the wild, although in captivity on average they live 16 years. See mortality for more information.
Social structure
Wolves function as social predators and hunt in packs organised according to a strict social hierarchy and led by an alpha male and alpha female. This social structure was originally thought to allow the wolf to take prey many times its size; new theories are emerging, however, that suggest the pack strategy instead maximizes reproductive success and has less to do with hunting.
The size of the pack may change over time and is controlled by factors including habitat type, individual personalities, and food supply. Generally packs contain between two and six animals, although packs with more than 20 have been recorded. The hierarchy or rank order of the pack is relatively strict, with the alphas (one male, one female) on top and the omega at the bottom. The hierarchy affects all activity in the pack, from which wolf eats first to which is allowed to breed (generally only the alpha pair).
The alpha pair have the most social freedom of all the animals in a pack, but they are not "leaders" in the sense humans usually think of the term. They do not give the other wolves orders. The alphas simply have the most freedom to choose where they would like to go and what they would like to do, and the rest of the pack usually follows along.
While most alpha pairs are monogamous with each other, there are exceptions. An alpha animal may preferentially mate with a lower ranking animal, especially if the other alpha is closely related (a brother or sister, for example). Wolves also do not "mate for life". The death of one alpha does not affect the status of the other alpha, who will usually just take another mate.
Rank order is established and maintained through a series of ritualized fights and posturings best described as ritual bluffing. Wolves prefer psychological warfare to actual fighting and high ranking status is based more on personality or attitude than on size or strength. Rank, who holds it, and how it is enforced varies widely between packs and between individual animals. In large packs full of easygoing animals, or in a group of juvenile animals, rank order may shift almost constantly, or even be circular (animal A dominates animal B who dominates animal C who dominates animal A).
Loss of rank can happen gradually or suddenly. An older wolf may simply choose to give way when an ambitious challenger presents itself, and rank will shift without bloodshed. Or the older animal may choose to fight back, with varying degrees of intensity. While an extremely high percentage of wolf aggression is non-damaging and ritualized, a high-stakes fight can result in injury. The loser of such a damaging fight is frequently chased away from the pack, or, rarely, may be killed as other, aggressively aroused wolves attempt to join in. This kind of dominance fight is more common in the winter months, when mating occurs.
Usually, only the alpha pair are able to successfully rear a litter of pups. (Other wolves in a pack may breed, and may even produce pups, but usually they lack the freedom or the resources to raise the pups to maturity.) All the wolves in the pack assist in raising wolf pups. Some pups may choose to stay in the original pack to reinforce it and help rear more pups while others disperse.
New packs are formed when a wolf leaves its birth pack and claims a territory. Wolves searching for other wolves with which to form packs can travel very long distances in search of suitable territories. Dispersing individuals must avoid the territories of other wolves because intruders on "owned" territories are chased away or killed. This probably explains wolf "predation" of dogs. Most dogs do not have much of a chance against a wolf protecting its territory from the unwanted intrusion.
Hunting
The wolf is somewhat opportunistic and will eat what it comes across as long as it is reasonably fresh. Packs of wolves hunt any large herbivore in their range, while lone wolves are more prone to take and eat anything that comes across, including rodents. The hunting methods ranges from surprise attacks on smaller animals such as rabbits and rodents to long lasting chases. Wolves can chase large prey for several hours before giving up, but the success rate is rather low.
Livestock predation
As long as there are enough prey animals, wolves seem to avoid taking livestock. However, some problem animals can specialize in hunting livestock. Sheep are frequently the most vulnerable, while horses and cattle are at less of a risk. Wolf-secure fences and the killing of problem animals are today the only known methods to effectively stop livestock predation.
In some countries (and over several centuries), shepherds and dog breeders have developed large livestock guarding dogs that can stand up to wolves preying on flocks. In the United States, as the timber wolf has been re-introduced the USDA has been looking into the use of breeds such as the Akbash, from Turkey, the Maremma from Italy, the Great Pyrenees from France and the Kuvasz from Hungary, among others.
Communication
Wolves communicate with a wide range of sounds, from yips and growls to howls. Howls are frequently used to summon the pack to a location, announce their presence to other packs or simply to reinforce the bounds in the pack. Wolves howl more frequently when they have something to protect, such as a freshly killed prey or a border of their territory, and less frequently when avoiding conflicts with other packs.
Reproduction
Normally, only the alpha pair of the pack breed. This kind of organization also occurs in other pack-hunting canids, such as the Dhole and the African Hunting Dog. Mating usually occurs in February to May and wolves, unlike dogs, only mate once a year. Another interesting fact about the social economy of wolves is that they are usually monogamous: the alpha pair will ordinarily mate exclusively with each other so long as they both remain alphas. There are times when one of the alphas will attempt to mate with a subordinate wolf, and if the other alpha is unable to prevent it multiple litters can be born. This has been documented in Yellowstone amongst other places and usually occurs in large packs with plenty of available prey.
The gestation period is 61–63 days and the pups are born completely dependent on their mother. The wolf is sexually mature at two years old.
Mortality
The oldest recorded free wolf was 16 years old. There have been reports of captive wolves reaching 20 years (not much unlike dogs). However the mean age of wolves is rather low. The mortality among pups is high; few survive the first winter. The most significant mortality factors for grown wolves are hunting and poaching by humans, car accidents, conflicts with other wolves, and wounds from hunting prey. All diseases that affect dogs also affect wolves, including mange and rabies, and can from time to time wipe out the wolf population in an area. Wolves adjust rather well to fluctuations in prey populations, so mass starvation is unusual.
Wolves can sustain their population under a heavy pressure, as long as the alpha pairs are not killed.
Taxonomy
Relation to the domestic dog
Much debate has occurred over the relationship between the wolf and the domestic dog. Most authorities see the wolf as the dog's direct ancestor, but others have postulated descent from the Golden Jackal. Because the canids have evolved recently and different canids interbreed fairly readily, untangling the true relationships has presented difficulties. However, molecular systematics now indicate very strongly that domestic dogs and wolves are more closely related than either is to any other canid, and the domestic dog is now normally classified as a subspecies of the wolf, Canis lupus familiaris.
Classification of the grey wolf
The classification of wolves and closely allied creatures offers many challenges. Although taxonomists have proposed many species over the years, most types clearly do not comprise true species. Indeed, only a single wolf species may exist. Scientists have proposed a host of subspecies. Many of these seem unlikely to stand. Further taxonomic clarification may well take decades.
Human attitudes towards wolves
The relationship between people and wolves has had a very long, and troubled, history. Historically, humans have often viewed wolves as a great danger or as nuisance to be destroyed. An opposing view, held by most biologists and naturalists, postulates that wolves form a valuable part of the ecosystem by hunting down deer and such, and require protection. Often these views occur simultaneously and cause conflicts among differing groups of people, as one sees when a wildlife service or organization attempts to preserve vanishing wolves or to reintroduce wolves to a habitat, like the rare red wolf.
Changing attitudes
In the late 20th century an increased awareness of the beneficial nature of wolves arose, encouraged by books like Never Cry Wolf by Farley Mowat and nature documentaries as well as by classification of the species as endangered. Accordingly, while the stereotype of wolves still has influence, a significant portion of the public has gained a positive opinion of wolves as interesting, valuable and even noble animals. Thus parks with a visible wolf population have often become popular tourist attractions. For instance, visitors to Yellowstone National Park can often see wolves from the roads.
Such organizations as the International Wolf Center attempt to educate people about the true nature of wolves, such action being helpful to the reintroduction process, especially in places such as Yellowstone National Park.
In other parks, tourists often participate in wolf howls, trying to make wolf-like howls in hopes that the resident wolves will answer. In fact, some nature-lovers have complained that this popularity has drawbacks since tourists sometimes intrude into wolf habitats and disturb them.
The large amount of research done on the wolf in the past half century has also helped to educate people and make them realize how sociologically similar humans are to wolves, and how we really have nothing to fear from these shy, majestic animals. Biologists such as L David Mech and Luigi Boitani have been major leaders in wolf research.
Nature documentaries have played a role changing attitudes. For instance, the film evidence of the wolf being a very social animal who is also a devoted parent to its young enlightened and charmed many viewers to a softer side to the feared predator.
Reintroduction
In the United States wolves are repopulating where they were eradicated and numbers have been increasing in Alaska and Minnesota where some packs remained in the deep forests despite bounty hunting and other past eradication efforts. Not only are they slowly but surely coming back naturally from Canada, they are also being successfully reintroduced in some states such as Idaho and Wyoming. It is curious to note that ranchers prefer reintroduction as they can kill wolves that eat their livestock and can get reimbursement for their loses, while truly wild animals are protected by law. In fact, wolf reintroduction was pushed hard by the U.S. Government, primarily by the U.S. Fish and Wildlife Service, who oversees threatened and endangered species within the United States. This includes several studies looking into the feasibility of reintroducing the wolf in places farther east, in areas like Adirondack State Park in New York and certain areas of Maine.
Recent studies have shown that the wolf would have enjoyed greater protection had they been allowed to repopulate areas on their own, without human intervention. Reports by wildlife biologists working for the National Park Service who stated that they had seen, though rarely, wolves in Yellowstone National Park, and had photographic proof of their limited presence prior to the "reintroduction", were essentially suppressed by the U.S. Fish and Wildlife Service.
Where wolves are reintroduced after a long absence, it has a marked influence on the coyote population. As they started to fill in the niche of the top predator, they started to grow bigger. With the return of the wolf these bigger coyotes are hunted down by wolves and go back to their previous niche.
In Sweden there is a long and ongoing conflict between some groups who claim that the wolf has no place in nature and that it has been reintroduced by the Swedish government with some kind of secret agenda.
Wolves in religion and folklore
In many ancient myths, the wolf was portrayed as brave, honourable, and intelligent. The best examples of these myths can be seen in those of the Native Americans. The wolf was also the revered totem animal of ancient Rome; see Romulus and Remus and Lupercalia. In Proto-Indo-European society, the wolf was probably associated with the warrior class (see also werewolf), and the term was subject to taboo deformation, the Latin lupus being an example of a mutated form of the original Proto-Indo-European *wlkwos. Many Germanic personal names used to include "wolf" as an element (e.g. Wulfstan).
In more modern western folklore, the wolf is a creature to be feared. The iconic examples of this image are the werewolf and the Big Bad Wolf. Norse mythology includes several malevolent wolves: the giant Fenrisulfr, eldest child of Loki and the giantess Angrboda, who was feared and hated by the Aesir, and his children Skoll and Hati, who devour the sun and moon at Ragnarok.
Human fear of the wolf is responsible for most of the trouble the species has received, and the reason it was nearly hunted out of existence. However, in the 20th century, with the new knowledge of wolves and the growing respect for Native American folklore, the animal has been generally depicted much more positively.
Despite their often negative image, wolves have variously been credited, in mythology, fiction and reality, with adopting, nursing and raising human feral children, the most famous examples being Romulus and Remus and Mowgli of The Jungle Book.
Wolf hunting
Wolves are hunted for the pelt and to control the numbers. Previously anything was used to kill wolves, including large amount of poisons. Some of the more diabolic creations of mankind have been used to kill wolves during the extermination campaigns in Europe and America. Today most of the hunting is done on the ground or from helicopters, either with shotguns or rifles. Hunting from airplanes or helicopters is usually only legal for state officials. Wolves are considered hard to hunt, and can go far after being shot.
Trapping
Wolves are frequently trapped, in the areas where it is legal, using snares or leg hold traps. The economic value of wolf pelts is limited, so it is mainly a recreation activity. Wolf trapping has come under heavy fire from animal rights groups and is used to attack other forms of trapping and hunting. It is alleged that trapping, using the right tools and equipment, can be considered as humane as hunting; however, unskilled trappers can create a lot of pointless suffering.
Breeding
Wolves are bred in a few locations. They are rather problematic animals to breed, and combined with the low value of the pelt it has driven most of the farms to change to other animals, such as fox.
Subspecies of the wolf
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The subspecies for the grey wolf has been a very controversial issue among taxonomists. It was once believed there were as many as 50 separate subspecies. However, the last decade has seen a new and widely accepted list which has been condensed to 13 living subspecies, and 2 recently extinct subspecies. This takes into account the anatomy, distribution and migration of various wolf colonies.
- Grey Wolf (Canis lupus)
- Tundra Wolf (Canis lupus albus) - Northern Russia and Finland.
- Arabian Wolf (Canis lupus arabs) - Arabia.
- Arctic Wolf (Canis lupus arctos) - The Arctic circle.
- Mexican Wolf (Canis lupus baileyi) - now only Arizona.
- Russian Wolf (Canis lupus communis) - Central Russia.
- Caspian Sea Wolf (Canis lupus cubanensis) - between the Caspian Sea and the Black Sea.
- Hokkaido Wolf (Canis lupus hattai) - Extinct.
- Honshu Wolf (Canis lupus hodophilax) - Extinct.
- Italian Wolf (Canis lupus italicus) - Italian Peninsula.
- Egyptian Wolf (Canis lupus lupaster) - Egypt and Libya.
- Eurasian Wolf (Canis lupus lupus) - from China, Mongolia, Russia and Eastern Europe to Germany.
- Eastern Timber Wolf (Canis lupus lycaon) - South East Canada and North East USA.
- Great Plains Wolf (Canis lupus nubilus) - North West USA, West and South East Canada.
- Mackenzie Valley Wolf (Canis lupus occidentalis) - Western Canada and Alaska.
- Indian Wolf (Canis lupus pallipes) - From India to the Middle East.
See also
Clipart and Animal Pictures
- Clipart (https://classroomclipart.com/image/category/clipart.htm)
- Animal Clipart (https://classroomclipart.com/image/category/animal-clipart.htm)
- Animal Animated Clipart (https://classroomclipart.com/clipart/Animations/Animals.htm)
- Pictures of Animals (https://classroomclipart.com/image/category/animal-photos.htm)
- Amphibian Clip Art, Pictures and Photogaphs (https://classroomclipart.com/image/category/amphibian-clipart.htm)
- Farm Animal Clip Art, Pictures and Photographs (https://classroomclipart.com/image/category/farm-animal-clipart.htm)
- Mammal Clip Art, Pictures and Photographs (https://classroomclipart.com/image/category/mammal-clipart.htm)
- Marine Animal Clip Art, Pictures and Photographs (https://classroomclipart.com/image/category/marine-life-clipart.htm)
- Reptile Clip Art, Pictures and Photographs (https://classroomclipart.com/image/category/reptile-clipart.htm)
- Spider Clip Art, Pictures and Photographs (https://classroomclipart.com/image/category/spider-clipart.htm)
External links
- International Wolf Center (http://www.wolf.org/wolves/index.asp)
- Canids.org (http://www.canids.org/SPPACCTS/greywolf.htm)
- USDA site on livestock guarding dogs and predators (http://www.nal.usda.gov/awic/companimals/guarddogs/livestockguarddogs.htm)
- Wolf Park (http://www.wolfpark.org)
- The Iberian Wolf (http://www.iberianature.com/material/wolf.html) Wolves in Spain