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Hyenas
Jan 11, 2012 11:30:02 GMT -5
Post by Atheron on Jan 11, 2012 11:30:02 GMT -5
AardwolfInformation from WikipediaThe Aardwolf (Proteles cristatus) is a small insectivorous hyena-like mammal, native to Eastern and Southern Africa. The name means "earth wolf" in Afrikaans. It is also called "maanhaar-jackal" and "protelid". Unlike true hyenas, the aardwolf is a defenceless animal whose diet almost completely consists of termites, other insect larvae and carrion. The natural enemies are deterred by the superficial resemblance to the more aggressive hyena species. The aardwolf is the only surviving species of the subfamily Protelinae. Two geographically separate subspecies are recognized: Proteles cristatus cristatus of Southern Africa, and Proteles cristatus septentrionalis of Eastern and Northeastern Africa. It is usually placed in the Hyaenidae, though formerly separated in another family (Protelidae). Physical CharacteristicsThe aardwolf looks most like the Striped Hyena, but is significantly smaller and has a more pointed muzzle, sharper ears used for listening for harvester termites, black vertical stripes on a coat of yellowish fur, and a long, distinct mane down the middle line of the neck and back, which is raised during a confrontation to make the aardwolf's size appear bigger. It is 22–31.5 inches long, excluding its bushy 8–11.8 inch tail, stands about 15.7–20 inches at the shoulder, and weighs between 19.8 and 31 pounds. Its front feet have 5 toes. Its teeth and skull are similar to that of the hyena, although the cheek teeth are specialised for eating insects, and its tongue for licking them up. As the aardwolf ages, it will normally lose some of its teeth, though this has little impact on their feeding habits due to the soft nature of the insects they consume. It has two glands at the rear that secrete a musky fluid for marking territory and communicating with other aardwolves. BehaviorAardwolves are shy and nocturnal, sleeping in underground burrows by day.They usually use existing burrows of aardvarks, Old World porcupines or springhares, despite being capable of creating their own. By night, an aardwolf can consume up to 200,000 harvester termites using its sticky, long tongue. They take special care not to destroy the termite mound or consume the entire colony, which ensures that the termites can rebuild and provide a continuous supply of food. They will often memorise and return to nests to save the trouble of finding a new one. They are also known to feed on other insects, larvae, and eggs, and occasionally small mammals and birds. Unlike other hyenas, it does not scavenge or kill larger animals because of its weak jaw and small size. The aardwolf is primarily solitary (especially with the males), but a mating pair will occupy the same territory with their young. Young aardwolves generally achieve sexual maturity after two years, and the breeding season varies depending on their location, but normally takes place during the autumn or spring. During the breeding season, male aardwolves will search their own territory as well as others' for a female to mate with. This can often result in conflict between two male aardwolves when one has wandered into another's territory. Gestation lasts between 90 and 110 days, producing 1 to 5 cubs (though it is normally between 2 and 3) during the rainy season when termites are active. The first six to eight weeks are spent in the den with the mother. After three months, they begin supervised foraging and by four months are normally independent. However, they will often use the same den as their mother until the next breeding season. They can achieve a lifespan of up to 15 years when in captivity.
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Hyenas
Jan 11, 2012 11:32:32 GMT -5
Post by Atheron on Jan 11, 2012 11:32:32 GMT -5
Brown HyenaInformation from WikipediaThe brown hyena (Parahyaena brunnea, formerly Hyaena brunnea) lives mainly in the Kalahari and Namib deserts of southern Africa. The intermediate-sized extant hyena, this species is 43–53 in in body length, 25–35 in tall at the shoulder and weighs 82–121 lb, though exceptional larger individuals are known. It is smaller than the Spotted Hyena, and unlike its spotted cousin, is largely a scavenger. It is the largest land animal to derive most of its diet from scavenging, although they will also hunt small mammals. Because of the scarcity of food in the desert, the brown hyena supplements its diet with fruit and vegetables, and along the Namib coastline they are known to snatch seal pups. Like spotted hyena, the brown hyena lives in clans. However, brown hyena clans are much smaller (ranging between 4 and 15 members) and less organized, and do not hunt cooperatively. A particularly large food source may draw several of the clan to it, and they will work together to defend their find. They will also defend their territories as a group. Brown hyena can generally chase off leopard, caracal or cheetah, but spotted hyena will drive them from kills. Brown hyena often feed from lion kills, but lions dominate and occasionally kill brown hyena. Unlike the spotted hyena, the females do not have enlarged clitoris, and males are slightly larger than females. The brown hyena is a nocturnal mammal and may travel great distances (30 km) in search of food which is located predominantly by a highly developed sense of smell. Like the other ‘true’ hyenas, it is predominately a scavenger; a bone crusher which is able to digest bone, horns and teeth. However it is an extremely adaptable feeder and an opportunistic hunter which enables it to survive in the harsh Kalahari desert where no other large carnivores can. Moreover, brown hyenas have a large and extremely efficient digestive system and do not need to drink surface water. They are able to conserve water by being nocturnal, and some individuals use aardvark holes during the day to escape the heat; these holes are below the water table and contain fresh water.When available during the rain season, browns will frequently visit water holes to drink, but the majority of their water intake comes from their food sources such as plants and fresh carcasses. In some parts of the desert Ostrich eggs provide a source of liquid, but fruits such as tsama melons and Gemsbok cucumber are the hyaena’s preeminent source of water; having a moisture content of around 90% and also containing vitamin C. The seeds of the cucumber and melon are ingested by the hyena and are expelled in the feces undamaged, and growth of tsama melons has been recorded at old dens and latrines. Thus brown hyenas are thought to be important vectors for seed dispersal. In addition to supplementing its diet with fruits and fungi such as the berries from the Brandy bush and Kalahari truffles respectively, brown hyenas will also consume insects and small vertebrate prey, with studies showing insects and reptiles are more frequently consumed by hyenas in the southern Kalahari than in the central Kalahar. Brown hyenas do hunt, but unlike the highly specialised cooperative hunting of spotted hyenas, the browns technique is regarded as a ‘primitive chase and grab affair’. In a study in the Southern Kalahari, only 4.2% of the diet consisted of hunted vertebrates, and prey species are generally small, or medium sized, typically springhare, springbok and bat-eared foxes. Such hunting is unspecialised and opportunistic, with the vast majority of hunts being unsuccessful, especially in comparison to the spotted hyena; brown hyenas have a 6% success rate in comparison to 31% success rate of spotted hyenas when hunting springbok lambs. Brown hyenas increase hunting attempts when carrion is less available such as in the dry season, but relative to the spotted hyena, hunting constitutes only a small fraction of the foraging budget of the brown hyena. A study by Mills showed that hunting accounted for only 5.8% of food biomass which was comprised of small species such as springhares, whereas for spotted hyenas, hunted prey accounted for 72.6% of food biomass, and was predominantly formed of ungulates (68%). Brown hyenas of the central Kalahari have been observed to stalk and to dig at borrows of springhare; there is no comment on the success rate of these actions . Along the Namib coast, brown hyenas hunt Cape fur seal cubs, and scavenge the remains of adult seals and other marine organisms washed up on to the shore. Even though seal cubs are in abundance, the brown hyena shows a preference for scavenging rather than hunting . Of those seal cubs hunted and killed, the carcasses were never seen to be completely consumed, with only the brain and intestines being devoured. Hyenas of the Namib coast were also observed to chase after domestic dogs, flamingos and geckos, and scavenge human refuge. In agricultural areas, the diet consists of small indigenous vertebrates and livestock as carrion. Reports of brown hyaenas killing calves, lambs, sheep, goats and other small livestock have been documented, although is not very common and usually a single individual is responsible for the majority of kills. Preliminary data from a questionnaire investigating the economic damage inflicted by brown hyenas and other carnivores in non-protected areas throughout the north west province, reveals that although some farmers have reported damage to their livestock by brown hyenas, (some of which are credible, others less so) they are perceived by the farmers as a lesser threat to livestock than jackals and caracals. Brown hyenas have been observed to frequently cache food items, predominantly legs both fleshy and bone, storing them in dense bush around 100-600 m from the site of the kill to which the hyena returns the following night, or after the main carcass has been expended. This behaviour is suggested to be a method of competition with other brown hyenas; rather than eating quickly or engaging in aggressive encounters with other hyenas, (typical of spotted hyenas) an individual will compete at a carcass directly by quickly removing the legs for caching, or indirectly by competing for social status.
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Hyenas
Jan 11, 2012 11:35:37 GMT -5
Post by Atheron on Jan 11, 2012 11:35:37 GMT -5
Spotted HyenaInformation from WikipediaThe Spotted Hyena, or Laughing Hyena, (Crocuta crocuta) is a mammal of the order Carnivora. They are moderately large, terrestrial carnivores native to Africa. They are best known for croaking, birdlike bark that resembles the sound of hysterical human laughter. Though often labeled incorrectly as a scavenger, the spotted hyena is actually a powerful hunter, the majority of its nourishment being derived from live prey. Spotted hyenas are the most common predator in sub-saharan Africa, living in savannah, dry woodland and desert habitats. Physical CharacteristicsAlthough hyenas bear some physical resemblance to the Canidae, they are in fact members of a separate biological family which is most closely related to Viverridae. The spotted hyena is the largest current member of the family Hyaenidae. It is thought that the ancestors of the spotted hyena branched off from the true hyenas (striped hyenas) during the Pliocene era, 5.332 million to 1.806 million years ago. It ranges in body length from 37.2-60 inches, and stands from 30-36 inches at the shoulder. In East Africa, the normal weight range for the male (who is usually more lightly built than the female) is 80-121 pounds; whereas, the females normally weigh from 105-121 pounds. They tend to grow larger in Southern Africa, with females often reaching 70 kilograms (154 pounds) The fur's background colour is a cream to light brown, with irregular dark spots that fade with age. The muzzle is black. They have long, heavily muscled necks, lined with a coarse mane of reversed fur. The forequarters are more heavily built than the hindquarters, giving the hyena a distinctively sloping bear-like gait. Hyenas are built for endurance, possessing a very large heart which allows them to trot at 6 mph without tiring. During chases, hyenas have been clocked at running speeds of up to 30 mph for over 3 km. They are good swimmers, capable of controlling their buoyancy and walking at the bottom of pools whilst holding their breath. Spotted hyenas mark their territories by excreting an oily, yellow substance from their anal glands onto surrounding bushes and grass. To do this, the anal pouch is turned inside out, or everted. The anal glands are everted also as a submissive posture to dominant hyenas. Scent marking is also done by scraping the ground with the paws, which deposits scent from glands on the bottoms of the feet. Hyenas have extremely strong jaws in relation to their body size. In 2005, Dr. Brady Barr of the National Geographic measured the bite forces of many different animals, including spotted hyenas for the documentary Dangerous Encounters: Bite Force. A one year old cub had a bite measured at 603 pounds of force, leading to the postulation that a full grown adult could bite at over 1,000 pounds. This mandibular power, combined with its large pyramid shaped molars allows it to easily crush bone, even those of elephants. An experiment conducted in 1955 showed how the spotted hyena easily outclassed the much larger brown bear in bone crushing ability. It is often asserted in television and print that hyenas have the most powerful bite for their overall body mass when compared to other animals, although there is no scientific basis for this claim. They also have a very powerful digestive system with highly acidic fluids. This makes them capable of eating and digesting their entire prey, including skin, teeth, horns, bones and even hooves. This results in them having crusty white droppings, due to the amount of calcium they ingest. The hyenas digestive system is so efficient, it can even derive nourishment from mummified corpses. There are even reports of hyenas entering campsites and consuming aluminium pots and pans. Undigestible parts are vomited in the form of pellets. In the wild, the spotted hyena has an average lifespan of 12 years. In captivity, it can be extended to 25.
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Hyenas
Jan 11, 2012 11:38:53 GMT -5
Post by Atheron on Jan 11, 2012 11:38:53 GMT -5
Striped HyenaInformation from WikipediaThe Striped Hyena (Hyaena hyaena) is closely related to the Brown Hyena. It lives in Africa, the Middle East, Pakistan and western India. It is extinct in Europe, but can occasionally be spotted in Anatolia, Turkey. Striped Hyenas are largely scavengers, but will also eat small animals, fruit and insects. Larger subspecies are known to hunt animals as large as wild boar. They are nomadic, moving from water hole to water hole, but never straying more than 6 miles from one. Striped hyenas hunt in solitude but do congregate in small family groups. Like many other animals of hot climates, their ears radiate heat. The striped hyena is generally considered solitary, but has some social organization. It forages individually and is rarely seen in groups. It does, however, associate in small family groups at the den. The striped hyena live in the tropical savanna, grasslands, Semi-desert, scrub forest, and woodland. AppearanceThe Striped hyena has grayish-brown fur all over, with black stripes on their legs, torso, head and back. Their muzzle and ears are entirely black. They have a medium sized mane on their neck and shoulders. The striped hyena can erect the long hair on its mane and appear 38% bigger, which it does when it feels threatened. The Striped Hyena has a life span 10-12 years, but can live longer than this when kept in captivity. A large, powerful animal, the striped hyena is covered in pale tan to greyish fur, which is usually quite shaggy. Black stripes slide down its sides in a vertical arrangement, and the muzzle/face is usually dark with a black throat patch on the underside of the neck. From the nape of its neck down to the rump, the back is covered by a thick, erectile mane. This mane can be raised to make the hyena look quite large, and is used in displays against other striped hyenas. Striped hyenas frequently grab and shake each other by the neck in mock fighting rituals. The legs are long, and also striped, while the body and neck are thick and heavy-set. The tail is fluffy and reaches the hocks. Striped hyenas weigh from 57 to 90 pounds. Length is about 4 to 5 feet from head to tail, and they stand about 26.4 to 30 inches tall at the shoulder. There is not much difference between the sizes of the male and female. ReproductionFemales tend to come into sexual maturity at about 2-3 years, though pregnant females of only 15 months have been reported in the wild. The estrous cycle is about 45-50 days long, though the female is only fertile for one day during that time. Females can come into heat at any time of the year. Once the female has mated, gestation of the young takes about 88-92 days, and anywhere from 1-5 young are born, though usually there are only 2 cubs. Cubs open their eyes from 5-9 days after birth and start eating solid meat at 30 days, though they will continue to nurse for 4-5 months. Adults will bring food home to the den, which is usually in a crevice between rocks or in a hole dug by the parents.
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