Gray wolf

The gray wolf or grey wolf (Canis lupus), often known simply as the wolf, is the largest wild member of the Canidae family. Though once abundant over much of Eurasia and North America, the gray wolf inhabits a reduced portion of its former range due to widespread destruction of its territory, human encroachment, and the resulting human-wolf encounters that sparked broad extirpation. Even so, the gray wolf is regarded as being of least concern for extinction by the International Union for Conservation of Nature, when the entire gray wolf population is considered as a whole. Today, wolves are protected in some areas, hunted for sport in others, or may be subject to extermination as perceived threats to livestock and pets.

Gray wolves are social predators that live in nuclear families consisting of a mated pair which monopolises food and breeding rights, followed by their biological offspring and, occasionally, adopted subordinates. They primarily feed on ungulates, which they hunt by wearing them down in short chases. Gray wolves are typically apex predators throughout their range, with only humans and tigers posing significant threats to them.

DNA sequencing and genetic drift studies reaffirm that the gray wolf shares a common ancestry with the domestic dog. A number of other gray wolf subspecies have been identified, though the actual number of subspecies is still open to discussion.

In areas where human cultures and wolves are sympatric, wolves frequently feature in the folklore and mythology of those cultures, both positively and negatively.

Evolution

)]] Paleontological Museum]] The most likely ancestral candidate of the gray wolf is Canis lepophagus, a small, narrow skulled North American canid of the Miocene era, which may have also given rise to coyotes. Some larger, broader skulled C. lepophagus fossils found in northern Texas may represent the ancestral stock from which true wolves derive. The first true wolves began to appear at the end of the Blancan North American Stage and the onset of the early Irvingtonian. Among them was Canis priscolatrans, a small species closely resembling the red wolf, which colonised Eurasia by crossing the Bering land bridge. The new Eurasian C. priscolatrans population evolved into Canis etruscus, then Canis mosbachensis.

This primitive wolf closely resembled the modern southern wolf populations of the Arabian Peninsula and South Asia, which were once distributed in Europe in the early Quaternary glaciation until about 500,000 years ago (see Subspecies).

The now extinct Japanese wolves were descended from large Siberian wolves which colonised the Korean Peninsula and Japan, prior to its separation from mainland Asia, 20,000 years ago during the Pleistocene. During the Holocene, the Tsugaru Strait widened and isolated Honshu from Hokkaidō, thus causing climactic changes leading to the extinction of most large bodied ungulates inhabiting the archipelago. Japanese wolves likely underwent a process of island dwarfism 7,000–13,000 years ago in response to these climatological and ecological pressures. C. l. hattai (formerly native to Hokkaidō) was significantly larger than it southern cousin C. l. hodophilax, as it inhabited higher elevations and had access to larger prey, as well as a continuing genetic interaction with dispersing wolves from Siberia. 39 subspecies of gray wolf are recognised, including the red wolf and two subspecies of domestic dog, Canis lupus dingo and Canis lupus familiaris. Wolf subspecies are divided into two categories:

"Northern wolves": large sized, large brained wolves with strong carnassials which inhabit North America, Europe and northern Asia. small brains and weak carnassials. They may represent a relic population of early wolves, as they closely resemble fossil European wolves, The vocalisations of southern wolves have a higher proportion of short, sharp barking, and they seldom howl. It is likely that dogs and dingoes stem from this group.

Wolves in Central and East Asia are intermediate in form and size to northern and southern wolves. Differences in brain size are well defined in different wolf populations, with wolves in northern Eurasia having the highest values, North American wolves having slightly smaller brains, and the southern wolves having the smallest. Southern wolves have brains 5–10% smaller than northern wolves. Though different in behaviour and morphology, northern and southern wolves can still interbreed: the Zoological Gardens of London for example once successfully managed to mate a male European wolf to an Indian female, resulting in a cub bearing an almost exact likeness to its sire.

Domestication

and a lap dog. Though varied in appearance, domestic dog skulls can be consistently distinguished from wolf skulls by their shortened muzzles, broader palates, crowded teeth and the broad, heavy frontal shields at the top of their skulls.]] Studies on the genetic distance for mitochondrial DNA on dogs and Eurasian wolves confirmed that wolves are the exclusive ancestral species to dogs. Domestic dogs possess four mtDNA lineages, suggesting four independent domestication events. A later study identified mtDNA evidence suggesting a common origin from a single East Asian gene pool for all dog populations, while another, using a much larger data set of nuclear markers, points to the Middle East as the source of most of the genetic diversity in the domestic dog and a more likely origin of domestication events. A study by the Kunming Institute of Zoology found that the domestic dog is descended from wolves tamed less than 16,300 years ago south of the Yangtse river in China. Morphological comparisons have narrowed the likely ancestral subspecies of gray wolf to wolves of the Middle Eastern and South Asian variety. there are a number of physical and behavioural differences. Comparative studies on dog and wolf behaviour and anatomy have shown that dog physiology and most dog behaviours are comparable to those of young wolves, an example of neoteny and pedomorphism.

The tympanic bullae are large, confex and almost spherical in wolves, in contrast to dogs whose bullae are smaller, compressed and slightly crumpled. The premolars and molars of wolves are much less crowded, and have more complex cusp patterns. Dogs lack a pre-caudal gland, and enter estrus twice yearly, unlike wolves which only do so once annually., though it is almost impossible to distinguish similarly sized wolf and dog prints with certainty, though most dogs tend to have rounder paw prints than wolves.

Physical description

Anatomy

Gray wolves are slender, powerfully built animals with large, deeply descending ribcages and sloping backs. Their abdomens are pulled in, and their necks heavily muscled. Their limbs are long and robust, with comparatively small paws. The front paws have five toes each, while the back paws have four. The forelimbs are seemingly pressed into the chest, with the elbows pointed inward, and the feet outward. Females tend to have narrower muzzles and foreheads, thinner necks, slightly shorter legs and less massive shoulders than males. Wolves are very strong for their size, possessing sufficient strength to turn over a frozen horse or moose carcass.

They are also capable of running at speeds of 56–64 km (34–38 miles) per hour, and can continue running for more than 20 minutes, though not necessarily at that speed. In cold climates, wolves can reduce the flow of blood near their skin to conserve body heat. The warmth of the footpads is regulated independently of the rest of the body, and is maintained at just above tissue-freezing point where the pads came in contact with ice and snow. The intestines of adult wolves measure 460–575 cm, the ratio to body length being 4.13–4.62. The stomach can hold 7–9 kg (15–20 lb) of food The liver is relatively large, weighing 0.7–1.9 kg (1.6–4.2 lb) in males and 0.68–0.82 kg (1.5–1.8 lb) in females. The dental formula is: at The Museum of Zoology, St. Petersburg. Note the wolf's larger size and broader muzzle]] The teeth are heavy and large, being better suited to bone crushing than those of other extant canids, though not as specialised as those found in hyenas. The canine teeth are robust and relatively short (26 mm). as well as cut through half inch lassos with one snap.

They generally resemble German shepherds or huskies in bodily configuration, but are distinguishable from them by their orbital angle of 40°–45° rather than 53°–60°, Compared to coyotes, wolves are larger and have broader snouts, shorter ears, and a proportionately smaller brain case Compared to golden jackals, wolves are larger and heavier, and have proportionately longer legs, shorter torsos and longer tails. The teeth are overall less trenchant than the jackal's, particularly in the upper molars, which have lower cusps, are broader, and are more .

Dimensions

Gray wolves are the largest extant members of the Canidae, excepting certain large breeds of domestic dog. Adult wolves are 105–160 cm (41–63 in) in length and 80–85 cm (32–34 in) in shoulder height. measuring 29–50 cm (11–20 in) in length. The ears are in height, and the hind feet are 220–250 mm. Wolf weight varies geographically; on average, European wolves may weigh , North American wolves , and Indian and Arabian wolves .

Females in any given wolf population typically weigh 5–10 lbs less than males. and the former Soviet Union. The heaviest recorded gray wolf in North America was killed on 70 Mile River in east-central Alaska on July 12, 1939 and weighed ,

The winter fur is highly resistant to cold; wolves in northern climates can rest comfortably in open areas at −40° by placing their muzzles between the rear legs and covering their faces with their tail. Wolf fur provides better insulation than dog fur, and, as with wolverines, it does not collect ice when warm breath is condensed against it.

Coat colour ranges from almost pure white through various shades of blond, cream, and ochre to grays, browns, and blacks. Differences in coat colour between sexes are largely absent, though females may have redder tones. Fur colour does not seem to serve any camouflage purpose, with some scientists concluding that the blended colors have more to do with emphasizing certain gestures during interaction. Black coloured wolves (which occur through wolf-dog hybridisation) rarely occur in Eurasia, where interactions with domestic dogs has been reduced over the past thousand years due to the depletion of wild wolf populations. They are more common in North America; about half of the wolves in the reintroduced wolf population in Wyoming's Yellowstone National Park are black. Captive wolves are known to be able to detect what foods their handlers have eaten by smell. Their auditory perception is very sharp, being able to hear up to a frequency of 26kH, Their eyesight is not as powerful as that of dogs, though their night vision is the most advanced of the Canidae. Northern wolf packs tend not to be as compact or unified as those of African wild dogs and spotted hyenas, though they are not as unstable as those of coyotes. Southern wolves are more similar in social behaviour to coyotes and dingoes, living largely alone or in pairs. The average pack consists of 5–11 animals; 1–2 adults, 3–6 juveniles and 1–3 yearlings, though exceptionally large packs consisting of 42 wolves are known. Wolf packs rarely adopt other wolves into their fold, and typically kill them. In the rare cases where strange wolves are adopted, the adoptee is almost invariably a young animal of 1–3 years of age, while killed wolves are mostly fully grown. The adoption of a new member can be a lengthy process, and can consist of weeks of exploratory, non-fatal attacks in order to establish whether or not the newcomer is trustworthy. During times of ungulate abundance (migration, calving etc.), different wolf packs may temporarily join forces. Wolves as young as five months and as old as five years have been recorded to leave their packs to start their own families, though the average age is 11–24 months. Triggers for dispersal include the onset of sexual maturity and competition within the pack for food and breeding.

Reproduction

In areas with low wolf densities, wolves are generally monogamous. Mated pairs usually remain together for life if one of the wolves does not die. Upon the death of one mated wolf, pairs are quickly re-established. Since males often predominate in any given wolf population, unpaired females are a rarity. Polygamy does occur, but primarily in captive situations. Multiple litters are rarely successful, due to infanticide by the pack's females. The age of first breeding in wolves depends largely on environmental factors; when food is abundant, or when wolf populations are heavily managed, wolves can rear pups at younger ages in order to exploit the newly available resources. Captive wolves have been known to breed as soon as they reach 9–10 months, while the youngest recorded breeding wolves in the wild were 2 years old. Females are capable of producing pups every year, with one litter annually being the average. Unlike coyotes, wolves never reach reproductive senescence before they die. Incest rarely occurs, though inbreeding depression has been reported to be a problem for wolves in Saskatchewan and Isle Royale.

Estrus typically occurs in late winter, with older, multiparous females entering estrus 2–3 weeks earlier than younger females. Before the rut ensues, wolf packs will temporarily dissolve until the end of the mating season. Old females usually whelp in the den of their previous litter, while younger females typically den near their birthplace. The gestation period lasts 62–75 days, with pups usually being born in the summer period. The average litter consists of 5–6 pups. Litters of 14–17 occur 1% of the time. Litter sizes tend to increase in areas where prey is abundant. Wolves bear relatively large pups in small litters compared to other canid species. Pups are born blind and deaf, and are covered in short soft grayish-brown fur. They weigh 300–500 grams at birth, and begin to see after 9–12 days. The milk canines erupt after one month. Pups first leave the den after 3 weeks. At 1.5 months of age, they are agile enough to flee from danger. Mother wolves do not leave the den for the first few weeks, relying on the fathers to provide food for them and their young.

Denning and sheltering behaviour

Wolves use different places for their diurnal rest; places with cover are preferred during cold, damp and windy weather, while wolves in dry, calm and warm weather readily rest in the open. During the autumn-spring period, when wolves are more active, they willingly lie out in the open, whatever their location. Actual dens are usually constructed for pups during the summer period. When building dens, females make use of natural shelters such as fissures in rocks, cliffs overhanging riverbanks and holes thickly covered by vegetation. Sometimes, the den is the appropriated burrow of smaller animals such as foxes, badgers or marmots. An appropriated den is often widened and partly remade. On rare occasions, female wolves will dig burrows themselves, which are usually small and short with 1-3 openings. The den is usually constructed not more than 500 metres away from a water source. Resting places, play areas for the pups and food remains are commonly found around wolf dens. The odour of urine and rotting food emanating from the denning area often attracts scavenging birds such as magpies and ravens. As there are few convenient places for burrows, wolf dens are usually occupied by animals of the same family. Though they mostly avoid areas within human sight, wolves have been known to nest near domiciles, paved roads and railways.

Territorial behaviours

Wolves are highly territorial animals, and generally establish territories far larger than they require to survive in order to assure a steady supply of prey. Territory size depends largely on the amount of prey available: in areas with an abundance of prey, the territories of resident wolf packs are smaller. Wolf packs travel constantly in search of prey, covering roughly 9% of their territory per day (average 25 km/d or 15 mi/d). The core of their territory is on average , in which they spend 50% of their time. Prey density tends to be much higher in the territory's surrounding areas. Despite this higher abundance of prey, wolves tend to avoid hunting in the fringes of their territory unless desperate, due to the possibility of fatal encounters with neighboring packs. The size of their territory may increase when the pack's pups reach the age of 6 months, and thus have the same nutritional requirements as adults. The smallest territory on record was held by a pack of six wolves in northeastern Minnesota, which occupied an estimated 33 km². The largest was held by an Alaskan pack of ten wolves encompassing a 6,272 km² area. In some areas, wolves may shift territories during their prey's migration season.

Wolves defend their territories from other packs through a combination of scent marking, direct attacks and howling (see Communication). Scent marking is used for territorial advertisement, and involves urination, defecation and ground scratching. Scent marks are generally left every 240 metres throughout the territory on regular travelways and junctions. Such markers can last for 2–3 weeks, When scent marking and howling fail to deter strange wolf packs from entering another's territory, violent interactions can ensue. In fact, 91% of wolf fatalities occur within of the borders between neighboring territories. Because the consequences of trespassing can be fatal, such incursions are thought to be largely due to desperation or deliberate aggressiveness.), though they are not fussy eaters. Medium and small sized animals preyed on by wolves include marmots, hares, badgers, foxes, polecats, ground squirrels, mice, hamsters, voles and other rodents, as well as insectivores. They frequently eat waterfowl (particularly during their moulting period and winter, when their greasy and fatty meat helps wolves build up their fat reserves) and their eggs. Wolf packs in Astrakhan will hunt Caspian seals on the Caspian Sea coastline. Some wolf packs in Alaska and Western Canada have been observed to feed on salmon. Cannibalism is not uncommon in wolves; during harsh winters, packs often attack weak or injured wolves, and may eat the bodies of dead pack members. However, they are not known to eat their young as coyotes sometimes do. Humans are rarely, but occasionally preyed upon (see Attacks on humans). Wolves will supplement their diet with fruit and vegetable matter; they willingly eat the berries of mountain ash, lily of the valley, bilberries, blueberries and cowberry. Other fruits include nightshade, apples and pears. They readily visit melon fields during the summer months. The prey animals of North American wolves have largely continued to occupy suitable habitats with low human density, and cases of wolves subsisting largely on garbage or livestock are exceptional. Animals commonly preyed on by North American wolves include moose, white-tailed deer, elk, mule deer, mountain sheep and caribou.

Hunting and feeding behaviours

standing its ground, thereby increasing its chance of survival]] running, thereby decreasing its chance of survival]] Although wolf packs do cooperate strategically in bringing down prey, they do not do so as frequently or as effectively as lionesses do; unlike lions, wolves rarely remain with their pack for more than two years, thus they have less time to learn how to hunt cooperatively. Contrary to lion prides, food acquisition per wolf decreases with pack size. Overall, single wolves or mated pairs typically have higher success rates in hunting than do large packs. Single wolves have occasionally been observed to kill large prey such as moose, bison and muskoxen unaided. When hunting, wolves will attempt to conceal themselves as they approach their prey. With ungulate herds, they then either attempt to break up the herd, or isolate one or two animals from it. If the targeted animal stands its ground, the wolves either ignore it, or try to intimidate it into running. When chasing small prey, wolves will attempt to catch up with their prey as soon as possible. With larger animals, the chase is prolonged, in order to wear the selected prey out. Wolf packs may also set up ambush trails; Indian wolves have been observed to chase gazelle herds through ravines where other wolves lie in wait within holes dug prior to the hunt, while Russian wolves will set up ambushes near water holes, sometimes using the same site repeatedly. When attacking moose, they occasionally bleed it to death by biting its soft nose. With medium-sized prey such as sheep, wolves may grab the animal by the neck and stun it by jerking its head downward, hitting its nose on the ground. or during the denning period, when wolves require a ready supply of meat when denbound. Surplus killing may also occur when adult wolves are teaching their young to hunt.

The breeding pair typically monopolises food in order to continue producing pups. When food is scarce, this is done at the expense of other family members, especially non-pups. This is in marked contrast to the feeding behaviours of dholes and African wild dogs, who give priority to their pups when feeding. The breeding pair typically eats first, though as it is they who usually work the hardest in killing prey, they may rest after a long hunt and allow the rest of the family to eat unmolested. Once the breeding pair has finished eating, the rest of the family will tear off pieces of the carcass and transport them to secluded areas where they can eat in peace. Wolves typically commence feeding by consuming the larger internal organs of their prey, such as the heart, liver, lungs and stomach lining. The kidneys and spleen are eaten once they are exposed, followed by the muscles.

Relationships with other predators

Wolves typically dominate other canid species in areas where they are sympatric. In North America, incidences of wolves killing coyotes are common, with such incidences being especially common in winter, when coyotes feed on wolf kills. Wolves may attack coyote den sites, digging out and killing the pups. They rarely eat the coyotes they kill. There are no records of coyotes killing wolves, though coyotes may chase wolves if they outnumber them. Near identical interactions have been observed in Eurasia between wolves and golden jackals, with the latter's numbers being comparatively small in areas with high wolf densities. Wolves are the most important predator of raccoon dogs, killing large numbers of them in the spring and summer periods. Wolves also kill red, arctic and corsac foxes, usually in disputes over carcasses. They may eat the foxes they kill. In Asia, they may compete with dholes.

Brown bears are encountered by wolves in both Eurasia and North America. Generally, the outcome of such encounters depends on context: brown bears typically prevail against wolves in disputes over carcasses, while wolves mostly prevail against bears when defending their den sites. Both species will kill each other's young. Wolves will eat the brown bears they kill, while brown bears seem to only eat young wolves. American black bears occur solely in the Americas. Wolf interactions with black bears are much rarer than with brown bears, due to differences in habitat preferences. The majority of black bear encounters with wolves occur in the species' northern range, with no interactions being recorded in Mexico. Wolves have been recorded on numerous occasions to actively seek out black bears in their dens and kill them without eating them. Unlike brown bears, black bears frequently lose against wolves in disputes over kills. While encounters with brown and black bears appear to be common, polar bears are rarely encountered by wolves, though there are two records of wolf packs killing polar bear cubs. Wolves will also kill the cubs of Asian black bears. When attacking bears in daylight, wolf packs have been known to harry their quarry and wait till nightfall before making the final assault, as wolves have better night vision than bears.

Wolves may encounter striped hyenas in Israel and Central Asia, usually in disputes over carcasses. Hyenas feed extensively on wolf killed carcasses in areas where the two species interact. On a one to one basis, hyenas dominate wolves, though wolf packs can drive off single hyenas.

Large wolf populations limit the numbers of small to medium sized felines. Wolves encounter cougars along portions of the Rocky Mountains and adjacent mountain ranges. Wolves and cougars typically avoid encountering each other by hunting on different elevations. In winter however, when snow accumulation forces their prey into valleys, interactions between the two species become more likely. Although they rarely interact, wolves and cougars will kill each other, with packs of the former sometimes usurping the latter's kills. They hunt steppe cats, and may pose a threat to snow leopards. Wolves may reduce Eurasian lynx populations.

Other than humans, tigers appear to be the only serious predators of wolves. In areas where wolves and tigers share ranges, such as the Russian Far East, the two species typically display a great deal of dietary overlap, resulting in intense competition. Wolf and tiger interactions are well documented in Sikhote-Alin, which until the beginning of the 20th century, held very few wolves. It is thought by certain experts that wolf numbers increased in the region after tigers were largely eliminated during the Russian colonization in the late 19th and early 20th centuries. This is corroborated by native inhabitants of the region claiming that they had no memory of wolves inhabiting Sikohte-Alin until the 1930s, when tiger numbers decreased. Tigers depress wolf numbers, either to the point of localized extinction or to such low numbers as to make them a functionally insignificant component of the ecosystem. Wolves appear capable of escaping competitive exclusion from tigers only when human persecution decreases the latter's numbers. Today wolves are considered scarce in tiger inhabited areas, being found in scattered pockets, and usually seen traveling as loners or in small groups. First hand accounts on interactions between the two species indicate that tigers occasionally chase wolves from their kills, while wolves will scavenge from tiger kills. Tigers are not known to prey on wolves, though there are four records of tigers killing wolves without consuming them. This competitive exclusion of wolves by tigers has been used by Russian conservationists to convince hunters in the Far East to tolerate the big cats, as they limit ungulate populations less than wolves, and are effective in controlling the latter's numbers.

Communication

Body language

Postural communication in wolves is composed of a variety of facial expressions, tail positions and piloerection. Aggressive or self assertive wolves are characterised by their slow and deliberate movements, high body posture and raised hackles, while submissive ones carry their bodies low, sleeken their fur and lower their ears and tail. When breeding males encounter subordinate family members, they may stare at them, standing erect and still with their tails horizontal to their spine. The pre-caudal scent glands may play a role in expressing aggression, as combative wolves will raise the base of their tails whilst drooping the tip, thus positioning the scent glands at the highest point.

Two forms of submissive behaviour are recognised: passive and active. Passive submission usually occurs as a reaction to the approach of a dominant animal, and consists of the submissive wolf lying partly on its back and allowing the dominant wolf to sniff its anogenital area. Active submission occurs often as a form of greeting, and involves the submissive wolf approaching another in a low posture, and licking the other wolf's face. When wolves are together, they commonly endulge in behaviours such as nose pushing, jaw wrestling, cheek rubbing and facial licking. The mouthing of each other's muzzles is a friendly gesture, while clamping on the muzzle with bared teeth is a dominance display. Dominant wolves may assert themselves by straddling over a subordinate family member. At a kill, wolves will protect the carcass from afar from other wolves by flattening their ears outwardly, thus indicating that they are covering something belonging to them.

Howling

Wolves howl to assemble the pack (usually before and after hunts), to pass on an alarm (particularly at a den site), to locate each other during a storm or unfamiliar territory and to communicate across great distances. Male wolves give voice through an octave, passing to a deep bass with a stress on "O", while females produce a modulated nasal baritone with stress on "U". Pups almost never howl, while yearling wolves produce howls ending in a series of dog-like yelps. Howls used for calling pack mates to a kill are long, smooth sounds similar to the beginning of the cry of a horned owl. When pursuing prey, they emit a higher pitched howl, vibrating on two notes. When closing in on their prey, they emit a combination of a short bark and a howl. Lone wolves typically avoid howling in areas where other packs are present. Wolves do not respond to howls in rainy weather and when satiated. Barking has a fundamental frequency between 320–904 Hz,

Growling has a fundamental frequency of 380–450 Hz, The captive breeding of wolf-dog hybrids has proliferated in the United States, with 300,000 such animals being present there. Although wolves normally kill dogs, lone wolves may fraternise with guard or herding dogs as surrogate pack members. Most wolf-dog matings in the wild involve female wolves soliciting male dogs. Although wolf-dog hybridisation in Europe has raised concern among conservation groups fearing for the wolf's purity, an analysis on the mtDNA sequences show that introgression of dog genes into European wolf populations does not pose a significant threat. Also, as wolf and dog mating seasons do not fully coincide, the likelihood of wild wolves and dogs mating and producing surviving offspring is small. Like pure wolves, hybrids breed annually, though their mating season occurs 3 months earlier, with pups mostly being born in the winter period, thus lessening their chances of survival. At least two wolf-dog breeds have been created in Europe, the Saarlooswolfhond and the Czechoslovakian Wolfdog, both by crossing wolves with German shepherds. These eastern coyote populations also have fewer sweat glands in their pawpads than western coyotes, but have more than wolves. The red wolf is thought by certain scientists to be in fact a wolf/coyote hybrid rather than a unique species. Strong evidence for hybridization was found through genetic testing which showed that red wolves have only 5% of their alleles unique from either gray wolves or coyotes. Genetic distance calculations have indicated that red wolves are intermediate between coyotes and gray wolves, and that they bear great similarity to wolf/coyote hybrids in southern Quebec and Minnesota. Analyses of mitochondrial DNA showed that existing red wolf populations are predominantly coyote in origin.

Range and populations

The gray wolf was once the world's most widely distributed mammal, living north of 15°N latitude in North America and 12°N in Eurasia. Wolves tend to have difficulty adapting to human induced changes, and are often referred to as an indicator species; a species delineating an ecoregion or indicating an environmental condition such as a disease outbreak, pollution, species competition, or climate change. Wolves do not seem to be able to adapt as readily to expanding civilization the way coyotes do. While human expansion has seen an increase in the latter's numbers, it has caused a drop in those of the former.

Despite not being at risk for extinction, local populations of wolves are still threatened. One such threat is genetic bottlenecking caused by population fragmentation. Human populations have isolated small pockets of animals, which then suffer the effects of inbreeding. Studies have shown that the reproduction rate in wolves is strongly related to genetic diversity. Isolated wolf populations are greatly affected by the introduction of the alleles of even a single additional wolf.

Wolf populations generally seem to be stable or increasing in most, but not all, Bern Convention nations. Limiting factors in member nations include a lack of acceptance of wolves (particularly in areas where they have made a comeback) due to concerns on livestock and dog predation and competition with hunters. Although properly regulated wolf harvests and control have been largely accepted as compatible with maintaining wolf numbers to economically acceptable levels, overhunting and poaching are recognised as the main limiting factor in European wolf populations.

With the exception of Israel and Saudi Arabia, there is little information available on wolves in the Middle East. The Arabian Peninsula is home to an estimated 300–600 wolves which, though hunted year round in all Middle Eastern countries except Israel, are relatively stable and protected by the inaccessibility of the northern mountains and central and northern deserts. In India, wolves are classed as endangered, and number an estimated 800-3,000 individuals scattered among several remnant populations. In China and Mongolia, wolves are not protected except in reserves.

Wolves once ranged over much of North America north of Mexico City, save for parts of California. Today, their status varies by country, state and province. Canadian and Alaskan wolves number in thousands and are in excellent biological condition. Wolves have expanded from Canada to the northern Rocky Mountains since the 1970s, establishing themselves southward in Montana, Washington, Idaho and Wyoming. In 1994, wolves from Alberta and British Columbia were captured and introduced into Yellowstone National Park, where they had been extinct since the 1930s. A similar introduction took place in 1998 in the Apache National Forest in Arizona. A small, isolated group of wolves on Isle Royale is believed to be suffering from the effects of reduced genetic variability. In 1991, the population was reduced from 50 to 12 wolves. Studies have shown that this reduction has coincided with a 50% loss of allozyme heterozygosity.

Diseases and parasites

Because wolves travel great distances, they may play an important role in spreading and maintaining diseases in certain areas. Infectious diseases spread by wolves include brucellosis, tularemia, listeriosis and anthrax. Wolves may also suffer from rabies: wolves are a major host for the disease in Russia, Iran, Afghanistan, Iraq and India. Wolves also carry the Canine coronavirus, with infections being most prevalent in winter months.

However, gray wolf populations are remarkably resilient against disease outbreaks. Usually, a wolf displaying the first symptoms of disease will leave its pack, thus preventing the sickness from spreading to its pack mates. Wolves in the former Soviet Union have been recorded to carry over 50 different parasite species. Ticks carried by wolves include Ixodes ricinus, Dermacentor pictus and Sarcoptes scabiei (or mange mite). Unlike foxes, wolves rarely develop full blown mange. Other ectoparasites include biting lice, sucking lice and the fleas Pulex irritans and Ctenocephalides canis. Endoparasites include nematodes such as Toxascaris leonina and T. canis.

Other endoparasites include cestodes such as Taenia pisiformis, T. hydatigena, Echinococcus granulosus, Mesocestoidea lineatus, Dioctophyme renale and the adult phase of Multiceps multiceps. Wolves may carry Neospora caninum, which is of particular concern to farmers, as the disease can be spread to livestock; infected animals being three to thirteen times more likely to abort than those not infected. Wolves suffering from tapeworms may deliberately forego eating fresh meat in favour of putrified flesh, in order to rid themselves of the parasites.

Relationships with humans

In folklore and mythology

nursed by the She-wolf by Peter Paul Rubens Rome, Capitoline Museums]] Wolves appear prominently in the folklore and mythology of human cultures with which they are sympatric. In Norse and Japanese mythology, wolves were portrayed as almost god-like. In Japan (where wolves were known as ookami or "great god") grain farmers worshiped wolves at shrines and left food offerings near their dens, beseeching them to protect their crops from wild boars and deer, and Ainu, wolves were believed to be the ancestors of their race, while the Dena’ina believed wolves were once men, and viewed them as brothers. Wolves were linked to the sun in some Eurasian cultures. The Ancient Greeks and Romans associated wolves with the sun god Apollo, Wolves were sometimes associated with witchcraft in both northern European and some Native American cultures. In Norse mythology, the völva (witch) Hyndla and the giantess Hyrrokin are both portrayed as using wolves as mounts. In Navajo culture, wolves were feared as witches in wolf's clothing. In the Navajo language, the word for "witch" (mai-cob) is synonymous with "wolf". Similarly, the Tsilhqot'in believed that contact with wolves could cause mental illness and death. Wolves are referenced thirteen times in the Bible as symbols of greed and destructiveness.

Livestock and dog predation

, depicting wolves harassing a steer]] Livestock depredation has been one of the primary reasons for hunting wolves, and can pose a severe problem for wolf conservation. As well as causing economic losses, the threat of wolf predation causes great stress on livestock producers, and no foolproof solution of preventing such attacks short of exterminating wolves has been found. Wolves typically resort to attacking livestock when wild prey is depleted: in Eurasia, a large part of the diet of some wolf populations consists of livestock, while such incidences are rare in North America, where healthy populations of wild prey have been largely restored. However, certain wolves may become "addicted" to livestock, as the stomach lining of domestic ungulates has a higher fat content than that of wild herbivores. The majority of losses occur during the summer grazing period. Untended livestock in remote pastures are the most vulnerable to wolf predation. Some nations help offset economic losses to wolves through compensation programmes or state insurance. Sheep are the most commonly taken livestock species in Europe, domestic reindeer in northern Scandinavia, cattle and turkeys in North America, goats in India and horses in Mongolia. Different subspecies of wolf may preferentially target different animals: small bodied wolves rarely molest adult cattle, while large northern wolves are able to kill fully grown steers and sometimes horses unaided. The number of animals killed in single attacks varies according to species: most attacks on cattle and horses result in one death, while turkeys, sheep and domestic reindeer may be killed in surplus. Wolves mainly attack livestock when the animals are grazing, though they will occasionally break into fenced enclosures..

Wolves will kill dogs on occasion, with some wolf populations relying on dogs as an important food source. Also, the fighting styles of wolves and dogs differ significantly; while dogs typically limit themselves to attacking the head, neck and shoulder, wolves will make greater use of body blocks, and attack the extremities of their opponents. In Croatia, wolves kill more dogs than sheep, and wolves in Russia appear to limit stray dog populations. Wolves may display unusually bold behaviour when attacking dogs accompanied by people, sometimes ignoring nearby humans. In some areas, livestock guardian dogs are fitted with wolf collars in order to protect themselves from wolf attacks. Wolves however may learn to avoid the spiked collars just as they do the antlers of ungulate prey, and still kill guard dogs. Wolf attacks on hunting dogs are considered a major problem in Scandinavia and Wisconsin. The most frequently killed hunting breeds in Scandinavia are harriers, with older animals being most at risk, likely because they are less timid than younger animals, and react differently to the presence of wolves. Wolf-caused injuries on dogs are often located on the back, thighs and hind legs. The fatal wound is mostly a bite to the back of the neck. Large hunting dogs such as Swedish elkhounds are more likely to survive wolf attacks due to their better ability to defend themselves. The number of people attacked and killed by wolves varies geographically. Wolf attacks on humans were a rare, but occasional feature of life in pre-20th century Europe: in France alone, historical records indicate that during the period 1580–1830, 3,069 people were killed by wolves, of whom 1,857 were killed by non-rabid wolves. Church and administrative accounts from Italy indicate that 440 humans were killed by wolves during the 15th and 19th centuries, occurring in the central part of the Po Valley, which once encompassed part of modern day Switzerland. Prior to 1882, 94 children under the age of 12 were killed in Fennoscandia by non-rabid wolves in a 300 year period. European Russia also records numerous attacks, particularly in pre-revolutionary times and after World War II. Between 1840 and 1861, 273 non-rabid attacks resulting in the deaths of 169 children and 7 adults occurred throughout Russia, while between 1944 and 1950, 22 children between the ages of 3 and 17 were killed by wolves in the Kirov Oblast (see Kirov wolf attacks). There are numerous documented accounts of wolf attacks in the Asian continent, with three Indian states reporting a large number of non-rabid attacks in recent decades. These attacks were well documented by trained biologists. In Hazaribagh, Bihar for example, 100 children were injured and 122 killed from 1980 to 1986. The North American continent has very few recorded incidences of such, It is thought that the reason why so fewer attacks are recorded in North America than in Eurasia is linked to the former's historically greater availability of firearms, whose usage taught North American wolves to fear humans more than their Eurasian counterparts. However, encounters with aggressive wolves in North America seem to be on the increase. One study revealed 80 events in Alaska and Canada where wolves closely approached or attacked people, finding 39 cases of aggression by apparently healthy wolves, and 29 cases of fearless behavior by nonaggressive wolves.

Recorded incidences of rabid wolves in Eurasia go far back as the 13th century. The number of cases of rabid wolves are however low when compared to other species. Wolves do not serve as primary reservoirs of the disease, but can catch it from other animals such as dogs, jackals and foxes. Cases of rabies in wolves are very rare in North America, though numerous in the eastern Mediterranean, Middle East and Central Asia. Wolves apparently develop the "furious" phase of rabies to a very high degree. This, coupled with their size and strength, make rabid wolves perhaps the most dangerous of rabid animals, with bites from rabid wolves being 15 times more dangerous than those of rabid dogs. Rabid wolves usually act alone, travelling large distances and often biting large numbers of people and domestic animals. Most rabid wolf attacks occur in the spring and autumn periods. Unlike with predatory attacks, the victims of rabid wolves are not eaten, and the attack generally only lasts a day. Also, the victims are chosen at random, though the majority of cases involve adult men.

Predatory attacks usually involve single wolves or packs that learn to exploit humans as prey. Such attacks may be preceded by a long period of habituation, in which wolves gradually lose their fear of humans. The victims are generally attacked in a sustained manner around the neck and face, and are then dragged off and consumed, unless the wolves are disturbed. Such attacks tend to cluster in time and space until the offending animals are killed. Also, wolves with pups experience greater food stresses during this period. The majority of victims of predatory wolf attacks are children under the age of 18 and, in the rare cases where adults are killed, the victims are almost always women. and will typically avoid investigating people who display self confident demeanors typical of being armed.

Hunting

(1862)]] Wolves are notoriously difficult to hunt due to their elusiveness, their sharp senses, their high endurance in the chase and ability to quickly incapacitate and kill hunting dogs. Historically, many methods have been devised to hunt wolves. In areas where wolves are a threat to livestock, the destruction of spring-born litters in their dens is a sure way of keeping wolf populations to a minimum. When hunting wolves with dogs, usually combinations of sighthounds, bloodhounds and fox terriers are used. The sighthounds chase and immobilise wolves until the arrival of the heavier dogs which do most of the fighting. Still hunting of wolves (alternately walking quietly and waiting concealed in the pursuit of game) is primarily practised in areas where the terrain is too rough for hunting with dogs, though wolves are almost as hard to hunt with this method as cougars are. The ideal time for wolf poisoning was during the late summer and early autumn period, when pups were more likely to stray from their mothers and consume objects which they had yet to learn to avoid. Foothold traps are effective, as long as no long lasting human odours are present on them. Many Native American tribes favoured deadfall traps in capturing wolves. Wolf traps are sometimes accompanied by scents (usually beaver or musk deer musk and wolf urine) or baits (venison or horse meat). Traps however are not foolproof; because of their excellent vision, wolves can detect the flaws in hidden traps, even at night, Hunting blinds can be effective against wolves, though they are seldom used, as their use requires much patience. A popular method of wolf hunting in Russia involves trapping a pack within a small area by encircling it with flag poles carrying a human scent. This method relies heavily on the wolf's fear of human scents, though it can lose its effectiveness when wolves become accustomed to the smell. Some hunters are able to lure wolves by imitating their calls, a method which is especially useful in winter and the mating season. In Kazakhstan and Mongolia, wolves are traditionally hunted with eagles and falcons, though this practise is declining, as experienced falconers are becoming few in number. Shooting wolves from aircraft is highly effective, as it allows greater visibility of wolves than hunting on the ground, though this method is controversial, as it allows wolves little chance to escape or defend themselves.

Fur use

Wolf pelts are primarily used for scarfs and the trimmings of women's garments, though they are occasionally used for jackets, short capes, coats, The pelts of wolves killed by poison are mostly worthless.

In Medieval Europe, pelts were considered the only practical aspect of wolves, though they were seldom used, due to the skin's foul odour. In Scandinavian folklore, wolf-skin girdles assisted in transforming the wearers into werewolves. Several Native American tribes used wolf pelts for medicinal purposes, The Pawnee wore wolf skins as capes when exploring enemy territories. The United States Army used wolf skin for parkas during the later stages of WWII and the Korean War to protect the faces of soldiers from frostbite. Wolf trapping for fur remains a lucrative source of income for many Native Americans. While dogs typically alter their behaviours to accommodate their handlers, the opposite is true for tame wolves. In contrast to dog pups, which are able to be socialised to humans at up to ten weeks of age, wolf pups are unable to do so after 19 days. Because wolf milk contains more arginine than can be found in puppy milk substitutes, an arginine supplement is needed when feeding pups below the weaning age. Failure to do so can result in the pups developing cataracts. Wolves lack any alteration of their predatory behaviour, and can thus not be fully trusted in situations where their prey drive can be given adequate stimulation. In contrast to dogs, which are usually accepting of strangers, treating them almost as an extension of their pack, wolves become increasingly xenophobic and intolerant of strangers not part of their immediate pack as they age. Pups under one year of age are generally not aggressive toward strangers, though their aggression increases with age, particularly during the mating season. Males may be more aggressive and difficult to handle than females. Once wolves learn how to escape confinement, it becomes near impossible to contain them.

Though wolves are trainable, they lack the same degree of tractability seen in dogs. They are generally not as responsive as dogs are to coercive techniques involving fear, aversive stimuli and force. Generally, far more work is required to obtain the same degree of reliability seen in most dogs. Even then, once a certain behavior has been repeated several times, wolves may get bored and ignore subsequent commands. Wolves are most responsive toward positive conditioning and rewards, though simple praise is not sufficient as in most dogs.

See also

California Wolf Center

Migration patterns of the gray wolf

References

Notes

Bibliography

Further reading

External links

California Wolf Center

The International Wolf Center

The IUCN Wolf Specialist Group

Watch Death of a Legend and Cry of the Wild by Bill Mason

Gray Wolf Category:Arctic land animals Category:Fauna of the Arctic Category:Mammals of Asia Category:Mammals of Europe Category:Mammals of North America Category:Megafauna of Eurasia Category:Megafauna of North America Category:Scavengers Category:Urban animals