Dhole
| Dhole | |
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| Genus: | Cuon Hodgson, 1838
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| Species: | C. alpinus
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| Binomial name | |
| Cuon alpinus | |
The dhole (Cuon alpinus) is a species of wild dog of the Canidae family. Not much is known about it. It is also known as the Asiatic Wild Dog; less known names include the Indian Wild Dog (where it is seen abundantly), the Red Dog, the Asiatic Dog, and the Whistling Hunter (due to the whistling sound it can make).
Within the canid family, the dhole is classified in a genus of its own, because it does not fit neatly in with any of the subspecies (e.g. the foxes or wolf-like dogs). The dhole has been a distinct species for several million years. “Cuon” means “Dog” in Greek, and “Alpinus” means “Alpine (Mountain)” in Latin. Thus the dhole’s scientific name means “mountain dog”.
The dhole is, generally, most active in the early morning and evening, and sometimes at night.
The dhole can reach at least 16 years of age in captivity, though 10 is common in the wild.
Habitat
The dhole exploits a large variety of habitats, reflecting its adaptability. It normally inhabits dry and moist deciduous forests and thick jungles, as well as tropical rain forests, which all provide better cover for hunting. It can also, however, survive in dense alpine forests, meadows and on the open steppes of Kashmir and Siberia. As the second part of its Latin name, Alpinus, suggests, the dhole is often found in hilly or mountainous regions. Dholes like open spaces and during the day they can often be found on jungle roads and paths, river beds, and in jungle clearings. The dhole inhabits in the widest range of climates in the canid family – from freezing cold to tropical heat.
Geographical Range
The dhole originates from South Asia. Its range is - latitude: 10 deg. South to 55 deg. North; Longitude: 70 deg. East to 170 deg. East. Though now little is known about the dhole’s distribution, its historical range extended from India to China, and down to Malaysia and Indonesia, with Java as the Southern limit. In recent decades, there has been huge habitat loss in this region, and restricted surveys indicate serious decline and fragmentation of the former range.
Nowadays, the dhole’s range extends from the borders of Russia and the Altai Mountains in Manchuria (Central and Eastern Asia) to the forest tracts of India, Burma, and the Malayan Archipelago. The best remaining populations are probably to be found in Central (especially in the Highlands) and Southern India.
Physical Description
Head and body length: 83 – 133cm (35 - 45in), though 100cm is the usual. Soviet Union populations are around 20% longer. Tail length: 28 - 50 centimeters (11-20in) Height at shoulder: 42 – 55cm (16 – 21in) Weight: Females weigh in at 10 - 16 kg, while males average 14 - 20 kg.
The dhole is about the size of a collie. Its coat is usually a uniformly rusty red hue, but varies regionally from sandy, creamy yellow through red and brown to dark gray. Generally, the dhole has a black-tipped – though sometimes white or brown or gray - moderately bushy tail, a darker area on its back, and white or pale patches on its chest, paws and belly. Its large ears are rounded with white on the inside, its legs are short, and its eyes are hooded and amber. The dhole has sixteen teats, reflecting its capability to care for many young. This is more teats than most other dogs. It has four toes on each paw, with fur between the toes.
Diet
The dhole eats almost all meat although it is classified as an omnivore. Its prey are usually deer (like spotted deer, chital, and sambar, which is over twenty times a dog’s weight), but also wild boar, wild goats, nilgai, mountain sheep, water buffalo, hares (like the black-naped hare), caribou, reindeer, guar and sometimes monkeys. On occasion, it will try for large creatures like the banteng, a large bovid. Also, the dhole may consume wild berries, insects, rodents, and lizards. In India, the dhole’s favorite prey animal is the medium-sized axis deer.
Dentition
The dhole has large, sharp teeth, and a shorter jaw and an unusually thicker muzzle than most other dogs. There is one less molar on each side of its lower jaw (meaning that they have forty teeth in total). Its dental formula (Incisors 3/3 : Canines 1/1 : Premolars 4/4 : Molars 2/2) is unique among the dog family.
Hunting
Although the dhole is not a fast runner, it has great stamina, and will pursue prey for hours. As it is an excellent swimmer, it will often drive its prey into water. The dhole is capable of killing prey ten times its own size, and will defend kills very violently. It has been seen killing bears and tigers.
Sometimes several families unite in order to hunt the larger animals. The dhole seldom kills by tearing out the throat. Larger mammals are attacked from behind and swiftly disemboweled, and smaller ones are caught by any part of the body and killed by a quick blow to the head. Often, a dhole pack will start on prey before it is even dead, like the African Hunting Dog does. The larger prey (which require a coordinated attack, frequently resulting in a “lead hunt dog” emerging by taking a prominent role in disabling the prey) more often die from the blood loss as its body parts are feasted upon rather than the attack itself. Two or three dholes can kill a 50 kg (110 lb) deer in less than two minutes.
Dhole packs compete for food, not by fighting, but by how fast they can consume it. An adult dhole can eat up to 4 kg (8.8 lb) of meat in one hour. When as a pack it can subdue prey over ten times its own body weight and can even attack leopards, the Indian bison, and tigers. Sometimes, however, the dhole prefers to hunt in a pair or singly.
Reproduction
Sexual maturity: Both males and females become sexually active at one year old. Mating season: Generally November – April, though variation is common, especially when it comes to different countries. Gestation period: 60 – 63 days. Litter size: Can range from 1 – 12, though 3 – 4 is most common. Lactation period: 8 weeks
The dhole breeds communally with most pack members helping to feed (by returning to the den and regurgitating flesh) and guard the young. In the breeding season, communal hunting is particularly important. Dens are constructed near streambeds or among rocks, often in burrows vacated by other animals, such as porcupines. Dens can vary from large multi-chambered complexes occupied over many generations, to simple scrapes below rocks where females may give birth. There have been reports of dens in farmland drainage pipes.
A cub is born a sooty brown color, acquiring an adult hue at around 3 months of age. Dhole young open their eyes at 2 weeks, begin to become more independent at 6 weeks, leave the den area at around 10 weeks, and join in with the rest of the pack to hunt at 7 months. Dholes mature at one year of age, and may or may not leave the pack (when dispersal takes place is unspecified). The gender ratio of dhole pups at birth is unknown.
Behavior
The dhole is a highly sociable and cooperative animal, like the Timber wolf, the Amazonian Bush Dog, and the African Hunting Dog. Generally it lives in organized, extended-family packs of five to twelve individuals (this number rarely exceeds twenty five), with more males, sometimes twice as many more, than females, and usually just one breeding female. Large packs of over forty dholes have been sighted, possibly resulting from the temporary fusion of neighboring packs. Within dhole packs, there is almost never any aggression – there is a strict social hierarchy, so fighting is not needed - or bullying.
The dhole has some extraordinary vocal calls. It can make high-pitched screams, mew, hiss, yelp, chatter, and cluck like a chicken. Its most well known sound is its strange whistle, which it uses to reassemble the pack when they become separated in dense forest areas. The whistle is so distinct that individual dholes can be identified by it.
The dhole can urinate while balancing on its front legs, and can jump at least 2.3 meters (7.5 feet).
Population Pressures
It is estimated that 2,500 mature individuals remain in the wild (mainly in wildlife sanctuaries and protected national parks), and the declining population trend is expected to continue.
One major threat to the dhole is habitat destruction (and thus loss of prey, which itself is amplified by excessive deer poaching). In India alone, over 40,000 square kilometres of forest has disappeared in the last 20 years. The main factors in this were logging, firewood collection, flooding due to dam construction, and agricultural expansion. Habitat deterioration fragments the dhole population, resulting in problems like disease and inbreeding, which have more permanent effects.
Human persecution, just as it does for the Timber wolf, also contributes to the dhole’s decline. The dhole is regarded as vermin – on rare occasions, dholes attack livestock, at the cost of the owner - and has therefore been shot, trapped, and poisoned. In India, bounties were paid for carcasses right up until when the dhole was declared a Protected Species under Schedule 1 of the Wildlife Act of 1972, which prohibits the killing of wildlife except in self-defense. Hunting in the Soviet Union has been prohibited since 1971. However, prejudice towards the dhole still exists. With suitable areas steadily diminishing and cattle being grazed within the forests, livestock occasionally fall prey to the dhole. If protection is not rigidly enforced, stockmen retaliate by excavating the den and clubbing the pups to death.
Further pressures are applied by local villagers who steal the dhole's kills for their own pot – dholes do not attack humans, and retreat at the sight of one, so this is easy to do. In this way, the dhole has become an indirect food source for the people of the jungle. In other regions such as Russia, poisons set out for wolves may be responsible for declines in the local dhole population. Non-human related factors which affect the dhole population include interspecific competition and disease transfer from domestic and feral dogs. There are no current research programmes investigating the dhole.
Subspecies
There are about eleven subspecies of the dhole, spanning different sizes and colors. Two subspecies of the dhole are classified as endangered by the World Conservation Union, meaning that they face serious risk of extinction. Another two are on the verge of extinction.
Cuon alpinus javanicus, found in Java, has a short, bright red coat, though there are regional variations. Cuon alpinus sumatrensis, found in Sumatra, has a short, bright red coat and dark whiskers. Cuon alpinus infuscus, found in Southern Myanmar, Malaysia, Thailand, and Vietnam has a dark brown coat and distinctive cranial features. Cuon alpinus adjustus, found in Northern Myanmar and Indo-China, has a reddish-brown coat. Cuon alpinus dukhunensis, found South of the Ganges in India, has a red coat, short hair on the paws, and black whiskers. Cuon alpinus primaevus, found in Himalayan regions of Nepal, Sikkim, and Bhutan, has a longer, redder coat than dukhunensis, and has long hair on the paws. Cuon alpinus hesperius, found in Eastern Russia and China, has a long, bright yellow coat with a white underside and pale whiskers. Cuon alpinus laniger, found in Kashmir and Southern Tibet, has a full yellow-gray coat. Cuon alpinus fumosus, found in Western Szechuan, China, and Mongolia, has a luxuriant yellowish-red coat with a dark back and gray neck. Cuon alpinus lepturus, found South of the Yangze in China, has a uniform red coat with thick under-fur. Cuon alpinus alpinus, found in Eastern Russia, including Amur, has a thick tawny-red coat with a grayish neck and an ochre muzzle.
Fictional appearances
Dholes appear in Rudyard Kipling's 1895 children's story "Red Dog" (originally published as "Good Hunting", subsequently included in The Second Jungle Book) as a threat to Mowgli's wolf pack, appearing somewhat more aggressive in the story than in real life.
References
- Template:IUCN2006 Database entry includes justification for why this species is endangered