Post by Hatzegopteryx on May 12, 2014 20:40:04 GMT
Spotted Hyena - Crocuta crocuta
Scientific Classification
Domain: Eukaryota
(Unranked): Opisthokonta
(Unranked): Holozoa
(Unranked): Filozoa
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Clade: Holotheria
Superlegion: Trechnotheria
Legion: Cladotheria
Sublegion: Zatheria
Infralegion: Tribosphenida
Subclass: Theria
Infraclass: Eutheria
Magnorder: Boreoeutheria
Superorder: Laurasiatheria
(unranked): Zooamata
(unranked): Ferae
(unranked): Carnivoramorpha
Order: Carnivora
Suborder: Feliformia
Family: Hyaenidae
Genus: Crocuta
Spotted Hyena range
The spotted hyena (Crocuta crocuta), also known as the laughing hyena, is a monospecific species of hyena native to Sub-Saharan Africa. It is listed as Least Concern by the IUCN on account of its widespread range and large numbers estimated between 27,000 and 47,000 individuals. The species is however experiencing declines outside of protected areas due to habitat loss and poaching. The species may have originated in Asia, and once ranged throughout Europe for at least one million years until the end of the Late Pleistocene. The spotted hyena is the largest member of the Hyaenidae, and is further physically distinguished from other species by its vaguely bear-like build, its rounded ears, its less prominent mane, its spotted pelt, and its more dual purposed dentition.
The spotted hyena is the most social of the Carnivora in that it has the largest group sizes and most complex social behaviours. Its social organisation is unlike that of any other Carnivore, bearing closer resemblance to that of cercopithecine primates (baboons and macaques) with respect to group-size, hierarchical structure, and frequency of social interaction among both kin and unrelated group-mates. However, the social system of the spotted hyena is openly competitive rather than cooperative, with access to kills, mating opportunities and the time of dispersal for males depending on the ability to dominate other clan-members. Females provide only for their own cubs rather than assist each other, and males display no paternal care. Spotted hyena society is matriarchal; females are larger than males, and dominate them.
The spotted hyena is a highly successful animal, being the most common large carnivore in Africa. Its success is due in part to its adaptability and opportunism; it is primarily a hunter but may also scavenge, with the capacity to eat and digest skin, bone and other animal waste. In functional terms, the spotted hyena makes the most efficient use of animal matter of all African carnivores. The spotted hyena displays greater plasticity in its hunting and foraging behaviour than other African carnivores; it hunts alone, in small parties of 2–5 individuals or in large groups. During a hunt, spotted hyenas often run through ungulate herds in order to select an individual to attack. Once selected, their prey is chased over long distance, often several kilometres, at speeds of up to 60 km/h.
The spotted hyena has a long history of interaction with humanity; depictions of the species exist from the Upper Paleolithic period, with carvings and paintings from the Lascaux and Chauvet Caves. The species has a largely negative reputation in both Western culture and African folklore. In the former, the species is mostly regarded as ugly and cowardly, while in the latter, it is viewed as greedy, gluttonous, stupid, and foolish, yet powerful and potentially dangerous. The majority of Western perceptions on the species can be found in the writings of Aristotle and Pliny the Elder, though in relatively unjudgemental form. Explicit, negative judgements occur in the Physiologus, where the animal is depicted as a hermaphrodite and grave robber. The IUCN's hyena specialist group identifies the spotted hyena's negative reputation as detrimental to the species' continued survival, both in captivity and the wild.
Spotted hyena with cubs at den site
Taxonomy, origins and evolution
Unlike the striped hyena, for which a number of subspecies were proposed in light of its extensive modern range, the spotted hyena is a genuinely variable species, both temporally and spatially. Its range once encompassed almost all of Africa and Eurasia, and displayed a large degree of morphological geographic variation, which led to an equally extensive set of specific and subspecific epithets. It was gradually realised that all of this variation could be applied to individual differences in a single subspecies. In 1939, biologist L. Harrison Matthews demonstrated through comparisons between a large selection of spotted hyena skulls from Tanzania that all the variation seen in the then recognised subspecies could also be found in a single population, with the only set of characters standing out being pelage (which is subject to a high degree of individual variation) and size (which is subject to Bergmann's Rule). When fossils are taken into consideration, the species displayed even greater variation than it does in modern times, and a number of these named fossil species have since been classed as synonymous with Crocuta crocuta, with firm evidence of there being more than one species within the genus Crocuta still lacking.
Both Björn Kurtén and Camille Arambourg promoted an Asiatic origin for the species; Kurtén focussed his arguments on the Plio-Pleistocene taxon Crocuta sivalensis from the Siwaliks, a view defended by Arambourg, who nonetheless allowed the possibility of an Indo-Ethiopian origin. This stance was contested by Ficarelli and Torre, who referred to evidence of the spotted hyena's presence from African deposists dating from the early Pleistocene, a similar age to the Asian C. sivalensis. Studies on the phylogeographic distribution of mtDNA haplotypes indicates three migration events from Africa to Eurasia, though neither the topology of the phylogenetic tree or the fossil record exclude the possibility of an Asian origin. The earliest migration of spotted hyenas from Africa to Eurasia began less than 3.5 million years ago, most probably from the area where the first spotted hyena fossils were discovered, reaching East Asia and most likely also Pakistan. The second migration of spotted hyenas occurred less than 1.3–1.5 million years ago and resulted in the first arrival of hyenas in Europe and a separation of African spotted hyenas into a southern and a northern population. The third spotted hyena migration took place 0.36 million years ago, starting from the northern African population and reaching both Europe and Asia. Unlike other African carnivores, with the exception of the leopard, there is no evidence to suggest that spotted hyenas underwent a genetic bottleneck during the Pleistocene.
The ancestors of the genus Crocuta diverged from Hyaena (the genus of striped and brown hyenas) 10 million years ago. The ancestors of the spotted hyena probably developed social behaviours in response to increased pressure from other predators on carcasses, which forced them to operate in teams. At one point in their evolution, spotted hyenas developed sharp carnassials behind their crushing premolars; this rendered waiting for their prey to die no longer a necessity, as is the case for brown and striped hyenas, and thus became pack hunters as well as scavengers. They began forming increasingly larger territories, necessitated by the fact that their prey was often migratory, and long chases in a small territory would have caused them to encroach into another clan's land. It has been theorised that female dominance in spotted hyena clans could be an adaptation in order to successfully compete with males on kills, and thus ensure that enough milk is produced for their cubs. Another theory is that it is an adaptation to the length of time it takes for cubs to develop their massive skulls and jaws, thus necessitating greater attention and dominating behaviours from females. Its appearance in Europe and China during the Cromerian period coincided with the decline and eventual extinction of Pachycrocuta brevirostris, the giant short-faced hyena. As there is no evidence of environmental change being responsible, it is likely that the giant short-faced hyena became extinct due to competition with the spotted hyena.
Spotted hyena camera trap image
Physical description
The spotted hyena has a strong and well developed neck and forequarters, but relatively underdeveloped hindquarters. The rump is rounded rather than angular, which prevents attackers coming from behind from getting a firm grip on it. The head is wide and flat with a blunt muzzle and broad rhinarium. In contrast to the striped hyena, the ears of the spotted hyena are rounded rather than pointed. Each foot has four digits, which are webbed and armed with short, stout and blunt claws. The paw-pads are broad and very flat, with the whole undersurface of the foot around them being naked. The tail is relatively short, being 300–350 mm (12–14 in) long, and resembles a pompom in appearance. Unusually among hyaenids, and mammals in general, the female spotted hyena is considerably larger than the male. The spotted hyena has a proportionately large heart, constituting close to 1% of its body weight, thus giving it great endurance in long chases. In contrast, a lion's heart makes up only 0.45–0.57 percent of its body weight. The now extinct Eurasian populations were distinguished from the modern African populations by their shorter distal extremities and longer humerus and femur.
The skull of the spotted hyena differs from that of the striped hyena by its much greater size and narrower sagittal crest. For its size, the spotted hyena has one of the most powerfully built skulls among the Carnivora. The dentition is more dual purposed than that of other modern hyena species, which are mostly scavengers; the upper and lower third premolars are conical bone-crushers, with a third bone-holding cone jutting from the lower fourth premolar. The spotted hyena also has its carnassials situated behind its bone-crushing premolars, the position of which allows it to crush bone with its premolars without blunting the carnassials. Combined with large jaw muscles and a special vaulting to protect the skull against large forces, these characteristics give the spotted hyena a powerful bite which can exert a pressure of 80 kgf/cm² (1140 lbf/in²), which is 40% more pressure than a leopard can generate. The jaws of the spotted hyena outmatch those of the brown bear in bonecrushing ability, and free ranging hyenas have been observed to crack open the long bones of giraffes measuring 7 cm in diameter.
Size
The spotted hyena is the largest extant member of the Hyaenidae. Adults measure 95–165.8 cm (37.4–65.3 in) in body length, and have a shoulder height of 70–91.5 cm (27.6–36.0 in). Adult male spotted hyenas in the Serengeti weigh 40.5—55.0 kg (89—121 lb), while females weigh 44.5—63.9 kg (98—141 lb). Spotted hyenas in Zambia tend to be heavier, with males weighing on average 67.6 kg (149 lb), and females 69.2 kg (153 lb). Exceptionally large weights of 81.7 kg (180 lb)1 and 90 kg (200 lb) are known. It has been estimated that adult members of the now extinct Eurasian populations weighed 102 kg (225 lbs).
Fur
Fur colour varies greatly and changes with age. Unlike the fur of the striped and brown hyena, that of the spotted hyena consists of spots rather than stripes and is much shorter, lacking the well defined spinal mane of the former two species. The base colour generally is a pale greyish-brown or yellowish-grey on which an irregular pattern of roundish spots is superimposed on the back and hind quarters. The spots, which are of variable distinction, may be reddish, deep brown or almost blackish. The spots vary in size, even on single individuals, but are commonly 20 mm (0.79 in) in diameter. A less distinct spot pattern is present on the legs and belly but not on the throat and chest. A set of five, pale and barely distinct bands replace the spots on the back and sides of the neck. A broad, medial band is present on the back of the neck, and is lengthened into a forward facing crest. The crest is mostly reddish-brown in colour. The crown and upper part of the face is brownish, save for a white band above both eyes, though the front of the eyes, the area around the rhinarium, the lips and the back portion of the chin are all blackish. The limbs are spotted, though the feet vary in colour, from light brown to blackish. The fur is relatively sparse and consists of two hair types; moderately fine underfur (measuring 15–20 mm (0.59–0.79 in)) and long, stout bristle hairs (30–40 mm (1.2–1.6 in)). European Paleolithic rock art depicting the species indicates that the Eurasian populations retained the spots of their modern-day African counterparts.
Behaviour
The spotted hyena is a social animal which lives in large communities called "clans", which can consist of up to 80 individuals. Group-size varies geographically; in the Serengeti, where prey is migratory, clans are smaller than those in the Ngorongoro Crater, where prey is sedentary. Spotted hyena clans are more compact and unified than wolf packs, but are not as closely knit as those of African wild dogs. Females dominate males, with even the lowest ranking females being dominant over the highest ranking males. It is typical for females to remain with their natal clan, thus large clans usually contain several matrilines, whereas males typically disperse from their natal clan at the age of 2½ years. The clan is a fission-fusion society, in which clan-members do not often remain together, but may forage alone or in small groups. High-ranking hyenas maintain their position through aggression directed against lower-ranking clan-members. Spotted hyena hierarchy is nepotistic; the offspring of dominant females automatically outrank adult females subordinate to their mother. However, rank in spotted hyena cubs is greatly dependent on the presence of the mother; low-ranking adults may act aggressively toward higher-ranking cubs when the mother is absent. Although individual spotted hyenas only care for their own young, and males take no part in raising their young, cubs are able to identify relatives as distantly related as great-aunts. Also, males associate more closely with their own daughters rather than unrelated cubs, and the latter favour their fathers by acting less aggressively toward them.
Spotted hyena societies are more complex than those of other carnivorous mammals, and are remarkably similar to those of cercopithecine primates in respect to group size, structure, competition and cooperation. Like cercopithecine primates, spotted hyenas use multiple sensory modalities, recognise individual conspecifics, are conscious that some clan-mates may be more reliable than others, recognise 3rd party kin and rank relationships among clan-mates, and adaptively use this knowledge during social decision making. Also, like cercopithecine primates, dominance ranks in hyena societies are not correlated with size or aggression, but with ally networks. In this latter trait, the spotted hyena further show parallels with primates by acquiring rank through coalition. However, rank reversals and overthrows in spotted hyena clans are very rare.
Territory size is highly variable, ranging from less than 40 km² in the Ngorongoro Crater to over 1,000 km² in the Kalahari. Home ranges are defended through vocal displays, scent marking and boundary patrols. Clans mark their territories by either pasting or pawing in special latrines located on clan range boundaries. Clan boundaries are usually respected; hyenas chasing prey have been observed to stop dead in their tracks once their prey crosses into another clan's range. Hyenas will however ignore clan boundaries in times of food shortage. Males are more likely to enter another clan's territory than females are, as they are less attached to their natal group and will leave it when in search of a mate. Hyenas travelling in another clan's home range typically exhibit bodily postures associated with fear, particularly when meeting other hyenas. An intruder can be accepted into another clan after a long period of time if it persists in wandering into the clan's territory, dens or kills.
Denning behaviour
The clan's social life revolves around a communal den. While some clans may use particular den sites for years, others may use several different dens within a year or several den sites simultaneously. Spotted hyena dens can have more than a dozen entrances, and are mostly located on flat ground. The tunnels are usually oval in section, being wider than they are high, and narrow down from an entrance width of ½–1 metre (1.6–7.7 ft) to as small as 25 cm (9.8 in). In the rocky areas of East Africa and Congo, spotted hyenas use caves as dens, while those in the Serengeti use kopjes as resting areas in daylight hours. Dens have large bare patches around their entrances, where hyenas move or lie down on. Because of their size, adult hyenas are incapable of using the full extent of their burrows, as most tunnels are dug by cubs or smaller animals. The structure of the den, consisting of small underground channels, is likely an effective anti-predator device which protects cubs from predation during the absence of the mother. Spotted hyenas rarely dig their own dens, having been observed for the most part to use the abandoned burrows of warthogs, springhares and jackals. Dens are used mostly by several females at once, and it is not uncommon to see up to 20 cubs at a single site. The general form of a spotted hyena den is tunnel-shaped, with a spacious end chamber used for sleeping or breeding. This chamber measures up to 2 metres (6.6 ft) in width, the height being rather less. Females generally give birth at the communal den or a private birth den. The latter is primarily used by low status females in order to maintain continual access to their cubs, as well as ensure that they become acquainted with their cubs before transferral to the communal den.
Intelligence
Compared to other hyenas, the spotted hyena shows a greater relative amount of frontal cortex which is involved in the mediation of social behavior. Studies strongly suggest convergent evolution in spotted hyena and primate intelligence. A study done by evolutionary anthropologists demonstrated that spotted hyenas outperform chimpanzees on cooperative problem-solving tests; captive pairs of spotted hyenas were challenged to tug two ropes in unison to earn a food reward, successfully cooperating and learning the maneuvers quickly without prior training. Experienced hyenas even helped inexperienced clan-mates to solve the problem. In contrast, chimps and other primates often require extensive training, and cooperation between individuals is not always as easy for them. The intelligence of the spotted hyena was attested to by Dutch colonists in 19th century South Africa, who noted that hyenas were exceedingly cunning and suspicious, particularly after successfully escaping from traps. Spotted hyenas seem to plan on hunting specific species in advance; hyenas have been observed to indulge in activities such as scent marking before setting off to hunt zebras, a behaviour which does not occur when they target other prey species. Also, spotted hyenas have been recorded to utilise deceptive behaviour, including giving alarm calls during feeding when no enemies are present, thus frightening off other hyenas and allowing them to temporarily eat in peace. Similarly, mothers will emit alarm calls in attempting to interrupt attacks on their cubs by other hyenas.
Hunting behaviour
Unlike other large African carnivores, spotted hyenas do not preferentially prey on any species, and only buffalo and giraffe are significantly avoided. Spotted hyenas prefer prey with a body mass range of 56–182 kg (123.5–401 lb), with a mode of 102 kg (224.9 lb). When hunting medium to large sized prey, spotted hyenas tend to select certain categories of animal; young animals are frequently targeted, as are old ones, though the latter category is not so significant when hunting zebras, due to their aggressive antipredator behaviours. The spotted hyena tracks live prey by sight, hearing and smell. Carrion is detected by smell and the sound of other predators feeding. During daylight hours, it watches vultures descending upon carcasses. Its auditory perception is powerful enough for it to detect sounds of predators killing prey or feeding on carcasses over distances of up to 10 km (6 mi). Unlike the grey wolf, the spotted hyena relies more on sight than smell when hunting, and does not follow its prey's prints or travel in single file. Small prey is killed by being shaken in the mouth, while large prey is eaten alive.
Spotted hyenas usually hunt wildebeest either singly, or in groups of two or three. They catch adult wildebeest usually after 5 km (3 mi) chases at speeds of up to 60 km/h (37 mi/h). Chases are usually initiated by one hyena and, with the exception of cows with calves, there is little active defense from the wildebeest herd. Wildebeest will sometimes attempt to escape hyenas by taking to water though, in such cases, the hyenas almost invariably catch them. Zebras require different hunting methods to those used for wildebeest, due to their habit of running in tight groups and aggressive defence from stallions. Typical zebra hunting groups consist of 10–25 hyenas, though there is one record of a hyena killing an adult zebra unaided. During a chase, zebras typically move in tight bunches, with the hyenas pursuing behind in a crescent formation. Chases are usually relatively slow, with an average speed of 15–30 km/h. A stallion will attempt to place himself between the hyenas and the herd, though once a zebra falls behind the protective formation it is immediately set upon, usually after a chase of 3 km (1.8 mi). Though hyenas may harass the stallion, they usually only concentrate on the herd and attempt to dodge the stallion's assaults. Unlike stallions, mares typically only react aggressively to hyenas when their foals are threatened. Unlike wildebeest, zebras rarely take to water when escaping hyenas. When hunting Thomson's gazelles, spotted hyenas usually operate alone, and prey primarily on young fawns. Chases against both adult and young gazelles can cover distances of 5 km (3 mi) with speeds of 60 km/h (37 mi/h). Female gazelles do not defend their fawns, though they may attempt to distract hyenas by feigning weakness.
Diet
The spotted hyena is very efficient at eating its prey; not only is it able to splinter and eat the largest ungulate bones, it is also able to digest them completely. Spotted hyenas can digest all organic components in bones, not just the marrow. They react to alighting vultures more readily than other African carnivores, and are more likely to stay in the vicinity of lion kills or human settlements.
Wildebeest are the most commonly taken medium sized ungulate prey item in both Ngorongoro and the Serengeti, with zebra and Thomson's gazelles coming close behind. Cape buffalo are rarely attacked due to differences in habitat preference, though adult bulls have been recorded to be taken on occasion. In Kruger National Park, blue wildebeest, cape buffalo, Burchell's zebra, greater kudu and impala are the spotted hyena's most important prey, while giraffe, impala, wildebeest and zebra are its major food sources in the nearby Timbavati area. Springbok and kudu are the main prey in Namibia's Etosha National Park, and springbok in the Namib. In the southern Kalahari, gemsbok, wildebeest and springbok are the principal prey. In Chobe, the spotted hyena's primary prey consists of migratory zebra and resident impala. In Kenya's Masai Mara, 80% of the spotted hyena's prey consists of topi and Thomson's gazelle, save for during the four-month period when zebra and wildebeest herds migrate to the area. Bushbuck, suni and buffalo are the dominant prey items in the Aberdare Mountains, while Grant's gazelle, gerenuk, sheep, goats and cattle are likely preyed upon in northern Kenya. In west Africa, it is thought that the spotted hyena is primarily a scavenger, but will occasionally attack domestic stock and medium-size antelopes in some areas. In Cameroon, it is common for spotted hyenas to feed on small antelopes like kob, but may also scavenge on reedbuck, kongoni, buffalo, giraffe, African elephant, topi and roan antelope carcasses. Records indicate that spotted hyenas in Malawi feed on medium to large-sized ungulates such as waterbuck and impala. In Tanzania's Selous Game Reserve, spotted hyenas primarily prey on wildebeest, followed by buffalo, zebra, impala, giraffe, reedbuck and kongoni. In Uganda, it is thought that the species primarily preys on birds and reptiles, while in Zambia it is primarily a scavenger.
Spotted hyenas have also been found to catch fish, tortoises, humans, black rhino, hippo calves, young African elephants, pangolins and pythons. There is at least one record of four hyenas killing an adult hippopotamus in Kruger National Park. The fossil record indicates that the now extinct European spotted hyenas primarily fed on Przewalski's horses, Irish elk, reindeer, red deer, roe deer, fallow deer, wild boar, ibex, steppe wisent, aurochs, and woolly rhinoceros. Spotted hyenas are thought to be responsible for the dis-articulation and destruction of some cave bear skeletons. Such large carcasses were an optimal food resource for hyenas, especially at the end of winter, when food was scarce. Spotted hyenas may consume leather articles such as boots and belts around campsites. Jane Goodall recorded spotted hyenas attacking or savagely playing with the exterior and interior fittings of cars, and the species is thought to be responsible for eating car tyres.
A single spotted hyena can eat at least 14.5 kg of meat per meal. Although spotted hyenas act aggressively toward each other when feeding, they compete with each other mostly through speed of eating, rather than by fighting as lions do. When feeding on an intact carcass, spotted hyenas will first consume the meat around the loins, then open the abdominal cavity and pull out the soft organs. Once the stomach, its wall and contents are consumed, the hyenas will eat the lungs and abdominal and leg muscles. Once the muscles have been eaten, the carcass is disassembled and the hyenas carry off pieces to eat in peace. Spotted hyenas are adept at eating their prey in water: they have been observed to dive under floating carcasses to take bites, then resurface to swallow. A single hyena can take less than two minutes in eating a gazelle fawn, while a group of 35 hyenas can completely consume an adult zebra in 36 minutes. Spotted hyenas do not require much water, and typically only spend 30 seconds drinking.
Enemies and competitors
In areas where spotted hyenas and lions are sympatric, the two species occupy the same ecological niche, and are thus in direct competition with one another. In some cases, the extent of dietary overlap can be as high as 68.8%. Lions typically ignore spotted hyenas, unless they are on a kill or are being harassed by them. There exists a common misconception that hyenas steal kills from lions, but most often it's the other way around. Lions will readily steal the kills of spotted hyenas; in the Ngorongoro Crater, it is common for lions to subsist largely on kills stolen from hyenas. Lions are quick to follow the calls of hyenas feeding, a fact demonstrated by field experiments, during which lions repeatedly approached whenever the tape-recorded calls of hyenas feeding were played. When confronted on a kill by lions, spotted hyenas will either leave or wait patiently at a distance of 30–100 metres until the lions have finished eating. In some cases, spotted hyenas are bold enough to feed alongside lions, and may occasionally force lions off a kill. This mostly occurs during the nighttime, when hyenas are bolder. Spotted hyenas usually prevail against groups of lionesses unaccompanied by males if they outnumber them 4:1. In some instances they were seen to have taken on and routed two pride males while outnumbering them 5:1. The two species may act aggressively toward one another even when there is no food at stake. Lions may charge at hyenas and maul them for no apparent reason; one male lion was filmed killing two hyenas on separate occasions without eating them, and lion predation can account for up to 71% of hyena deaths in Etosha. Spotted hyenas have adapted to this pressure by frequently mobbing lions which enter their territories. Experiments on captive spotted hyenas revealed that specimens with no prior experience with lions act indifferently to the sight of them, but will react fearfully to the scent.
Although cheetahs and leopards preferentially prey on smaller animals than those hunted by spotted hyenas, hyenas will steal their kills when the opportunity presents itself. Cheetahs are usually easily intimidated by hyenas, and put up little resistance, while leopards, particularly males, may stand up to hyenas. There are records of some male leopards preying on hyenas. Hyenas are nonetheless dangerous opponents for leopards; there is at least one record of a young adult male leopard dying from a septicemia infection caused by wounds inflicted by a spotted hyena.
Spotted hyenas will follow packs of African wild dogs in order to appropriate their kills. They will typically inspect areas where wild dogs have rested and eat any food remains they find. When approaching wild dogs at a kill, solitary hyenas will approach cautiously and attempt to take off with a piece of meat unnoticed, though they may be mobbed by the dogs in the attempt. When operating in groups, spotted hyenas are more successful in pirating dog kills, though the dog's greater tendency to assist each other puts them at an advantage against spotted hyenas, who rarely work in unison. Cases of dogs scavenging from spotted hyenas are rare. Although wild dog packs can easily repel solitary hyenas, on the whole, the relationship between the two species is a one sided benefit for the hyenas, with wild dog densities being negatively correlated with high hyena populations.
Spotted hyenas dominate other hyena species wherever their ranges overlap. Brown hyenas encounter spotted hyenas in the Kalahari, where the brown species outnumbers the spotted. The two species typically encounter each other on carcasses, which the larger spotted species usually appropriate. Sometimes, brown hyenas will stand their ground and raise their manes while emitting growls. This usually has the effect of seemingly confusing spotted hyenas, which will act bewildered, though they will occasionally attack and maul their smaller cousins. Similar interactions have been recorded between spotted and striped hyenas in the Serengeti.
Jackals will feed alongside hyenas, though they will be chased if they approach too closely. Spotted hyenas will sometimes follow jackals during the gazelle fawning season, as jackals are effective at tracking and catching young animals. Hyenas do not take to eating jackal flesh readily; four hyenas were reported to take half an hour in eating a golden jackal. Overall, the two animals typically ignore each other when there is no food or young at stake.
Spotted hyenas usually keep a safe distance from Nile crocodiles. Though they readily take to water to catch and store prey, hyenas will avoid crocodile infested waters.
Body language
Spotted hyenas have a complex set of postures in communication. When afraid, the ears are folded flat, and are often combined with baring of the teeth and a flattening of the mane. When attacked by other hyenas or by wild dogs, the hyena lowers its hindquarters. Before and during an assertive attack, the head is held high with the ears cocked, mouth closed, mane erect and the hindquarters high. The tail usually hangs down when neutral, though it will change position according to the situation. When a high tendency to flee an attacker is apparent, the tail is curled below the belly. During an attack, or when excited, the tail is carried forward on the back. An erect tail does not always accompany a hostile encounter, as it has also been observed to occur when a harmless social interaction occurs. Although they do not wag their tails, spotted hyenas will flick their tails when approaching dominant animals or when there is a slight tendency to flee. When approaching a dominant animal, subordinate spotted hyenas will walk on the knees of their forelegs in submission. Greeting ceremonies among clan-members consist of two individuals standing parallel to each other and facing opposite directions.
The spotted hyena has an extensive vocal range, with sounds ranging from whoops, fast whoops, grunts, groans, lows, giggles, yells, growls, soft grunt-laughs, loud grunt-laughs, whines and soft squeals. The loud "who-oop" call, along with the maniacal laughter, are among the most recognisable sounds of Africa. Typically, very high-pitched calls indicate fear or submission, while loud, lower-pitched calls express aggression. The pitch of the laugh indicates the hyena's age, while variations in the frequency of notes used when hyenas make noises convey information about the animal's social rank.
Range, habitat and population
The spotted hyena's distribution once ranged in Europe from the Iberian Peninsula to the Urals, where it remained for at least one million years. Remains have also been found in the Russian Far East, and it has been theorised that the presence of hyenas there may have delayed the colonisation of North America. The causes of the species' extinction in Eurasia are still largely unknown. In Western Europe at least, the spotted hyena's extinction coincided with a decline in grasslands 12,500 years ago. Europe experienced a massive loss of lowland habitats favoured by spotted hyenas, and a corresponding increase in mixed woodlands. Spotted hyenas, under these circumstances, would have been outcompeted by wolves and humans which were as much at home in forests as in open lands, and in highlands as in lowlands. Spotted hyena populations began to shrink roughly 20,000 years ago, completely disappearing from Western Europe between 14–11,000 years ago, and earlier in some areas.
Historically, the spotted hyena was widespread throughout Sub-Saharan Africa. It is present in all habitats save for the most extreme desert conditions, tropical rainforests and the top of alpine mountains. Its current distribution is patchy in many places, especially in West Africa. Populations are concentrated in protected areas and surrounding land. There is a continuous distribution over large areas of Ethiopia, Kenya, Tanzania, Botswana, Namibia and the Transvaal Lowveld areas of South Africa.
The species dwells in semi-deserts, savannah, open woodland, dense dry woodland, and mountainous forests up to 4,000m in altitude. It is scarce or absent in tropical rainforests and coastal areas. Its preferred habitats in west Africa include the Guinea and Sudan savannahs, and is absent in the belt of dense coastal forest. In the Namib Desert, it occurs in riverine growth along seasonal rivers, the sub-desertic pro-Namib and the adjoining inland plateau. In ideal habitats, the spotted hyena outnumbers other large carnivores, including other hyena species. However, the striped and brown hyena occur at greater densities than the spotted species in desert and semi-desert regions. Population densities based on systematic censuses vary substantially, from 0.006 to 1.7 individuals per km².
Attacks on humans
As with most mammalian predators, the spotted hyena is typically shy in the presence of humans, and has the highest flight distance (up to 300 metres) among African carnivores. However, this distance is reduced during the night, when hyenas are known to follow people closely. Although spotted hyenas do prey on humans in modern times, such incidences are rare. However, attacks on humans by spotted hyenas are likely to be underreported. Man-eating spotted hyenas tend to be very large specimens; a pair of man-eating hyenas, responsible for killing 27 people in Mlanje, Malawi in 1962 and were weighed at 72 kg (159 lb) and 77 kg (170 lb) after being shot. Victims of spotted hyenas tend to be women, children and sick or infirm men, and there are numerous cases of biologists in Africa being forced up trees in order to escape them. Attacks occur most commonly in September, when many people sleep outdoors, and bush fires make the hunting of wild game difficult for hyenas.
In 1903, Hector Duff wrote of how spotted hyenas in the Mzimba district of Angoniland would wait at dawn outside people's huts and attack them when they opened their doors. In 1908–09 in Uganda, spotted hyenas regularly killed sufferers of African sleeping sickness as they slept outside in camps. Spotted hyenas are widely feared in Malawi, where they have been known to occasionally attack people at night, particularly during the hot season when people sleep outside. Hyena attacks were widely reported in Malawi's Phalombe plain, to the north of Michesi Mountain. Five deaths were recorded in 1956, five in 1957 and six in 1958. This pattern continued until 1961 when eight people were killed. During the 1960s, Flying Doctors received over two dozen cases of hyena attacks on humans in Kenya. An anecdotal 2004 news report from the World Wide Fund for Nature indicates that 35 people were killed by spotted hyenas during a 12 month period in Mozambique along a 20 km stretch of road near the Tanzanian border.
Although attacks against living humans are rare, the spotted hyena readily feeds on human corpses. In the tradition of the Maasai and the Hadza, corpses are left in the open for spotted hyenas to eat. A corpse rejected by hyenas is seen as having something wrong with it, and liable to cause social disgrace, therefore it is not uncommon for bodies to be covered in fat and blood from a slaughtered ox. In Ethiopia, hyenas were reported to feed extensively on the corpses of victims of the 1960 attempted coup and the Red Terror. Hyenas habituated to scavenging on human corpses may develop bold behaviours towards living people; hyena attacks on people in southern Sudan increased during the Second Sudanese Civil War, when human corpses were readily available to them.
Urban hyenas
In some parts of Africa, spotted hyenas have begun to frequent metropolitan areas, where groups or "clans" of the animals have become a menace. The Ethiopian capital Addis Ababa is estimated to have up to a thousand resident hyenas which survive by scavenging rubbish tips and predating feral dogs and cats. There have also been attacks on humans living rough. In 2013 a baby boy was killed by hyenas after being snatched from his mother as she camped near the Hilton Hotel. Some 40 of the animals were reportedly seen alongside a fence bordering the British Embassy compound. In December 2013 a cull was organised and marksmen killed ten hyenas which had occupied wasteland near the city centre.
Spotted hyenas in captivity
From a husbandry point of view, hyenas are easily kept, as they have few disease problems and it is not uncommon for captive hyenas to reach 15–20 years of age. Nevertheless, the spotted hyena was historically scantily represented in zoos, and was typically obtained in order to fill empty cages until a more prestigious species could be obtained. In subsequent years, animals considered to be more charismatic were allocated larger and better quality facilities, while hyenas were often relegated to inferior exhibits. In modern times, the species faces spatial competition from more popular animals, especially large canids. Also, many captive individuals have not been closely examined to confirm their sexes, thus resulting in non-breeding pairs often turning out to be same-sexed individuals. As a result, many captive hyena populations are facing extinction.
During the 19th century, the species was frequently displayed in travelling circuses as oddities. Alfred Brehm wrote that the spotted hyena is harder to tame than the striped hyena, and that performing specimens in circuses were not up to standard. Sir John Barrow described how spotted hyenas in Sneeuberge were trained to hunt game, writing that they were "as faithful and diligent as any of the common domestic dogs". In Tanzania, spotted hyena cubs may be taken from a communal den by witchdoctors, in order to increase their social status. An April 2004 BBC article described how a shepherd living in the small town of Qabri Bayah about 50 kilometres from Jigjiga, Ethiopia managed to use a male spotted hyena as a livestock guardian dog, suppressing its urge to leave and find a mate by feeding it special herbs. If not raised with adult members of their kind, captive spotted hyenas will exhibit scent marking behaviours much later in life than wild specimens. Although easily tamed, spotted hyenas are exceedingly difficult to house train, and can be very destructive; a captive, otherwise perfectly tame, specimen in the Tower of London managed to tear an 8-foot (2.4 m) long plank nailed to its recently repaired enclosure floor with no apparent effort. During the research leading to the composition of his monograph The Spotted Hyena: A Study of Predation and Social Behavior, Hans Kruuk kept a tame hyena he named Solomon. Kruuk found Solomon's company so congenial, he would have kept him, but Solomon had an insatiable taste for "cheese in the bar of the tourist lounge and bacon off the Chief Park Warden's breakfast table," and no door could hold him back, so Solomon was obliged to live out his days in the Edinburgh Zoo.
South African zoologist with captive spotted hyenas
Scientific Classification
Domain: Eukaryota
(Unranked): Opisthokonta
(Unranked): Holozoa
(Unranked): Filozoa
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Clade: Holotheria
Superlegion: Trechnotheria
Legion: Cladotheria
Sublegion: Zatheria
Infralegion: Tribosphenida
Subclass: Theria
Infraclass: Eutheria
Magnorder: Boreoeutheria
Superorder: Laurasiatheria
(unranked): Zooamata
(unranked): Ferae
(unranked): Carnivoramorpha
Order: Carnivora
Suborder: Feliformia
Family: Hyaenidae
Genus: Crocuta
Spotted Hyena range
The spotted hyena (Crocuta crocuta), also known as the laughing hyena, is a monospecific species of hyena native to Sub-Saharan Africa. It is listed as Least Concern by the IUCN on account of its widespread range and large numbers estimated between 27,000 and 47,000 individuals. The species is however experiencing declines outside of protected areas due to habitat loss and poaching. The species may have originated in Asia, and once ranged throughout Europe for at least one million years until the end of the Late Pleistocene. The spotted hyena is the largest member of the Hyaenidae, and is further physically distinguished from other species by its vaguely bear-like build, its rounded ears, its less prominent mane, its spotted pelt, and its more dual purposed dentition.
The spotted hyena is the most social of the Carnivora in that it has the largest group sizes and most complex social behaviours. Its social organisation is unlike that of any other Carnivore, bearing closer resemblance to that of cercopithecine primates (baboons and macaques) with respect to group-size, hierarchical structure, and frequency of social interaction among both kin and unrelated group-mates. However, the social system of the spotted hyena is openly competitive rather than cooperative, with access to kills, mating opportunities and the time of dispersal for males depending on the ability to dominate other clan-members. Females provide only for their own cubs rather than assist each other, and males display no paternal care. Spotted hyena society is matriarchal; females are larger than males, and dominate them.
The spotted hyena is a highly successful animal, being the most common large carnivore in Africa. Its success is due in part to its adaptability and opportunism; it is primarily a hunter but may also scavenge, with the capacity to eat and digest skin, bone and other animal waste. In functional terms, the spotted hyena makes the most efficient use of animal matter of all African carnivores. The spotted hyena displays greater plasticity in its hunting and foraging behaviour than other African carnivores; it hunts alone, in small parties of 2–5 individuals or in large groups. During a hunt, spotted hyenas often run through ungulate herds in order to select an individual to attack. Once selected, their prey is chased over long distance, often several kilometres, at speeds of up to 60 km/h.
The spotted hyena has a long history of interaction with humanity; depictions of the species exist from the Upper Paleolithic period, with carvings and paintings from the Lascaux and Chauvet Caves. The species has a largely negative reputation in both Western culture and African folklore. In the former, the species is mostly regarded as ugly and cowardly, while in the latter, it is viewed as greedy, gluttonous, stupid, and foolish, yet powerful and potentially dangerous. The majority of Western perceptions on the species can be found in the writings of Aristotle and Pliny the Elder, though in relatively unjudgemental form. Explicit, negative judgements occur in the Physiologus, where the animal is depicted as a hermaphrodite and grave robber. The IUCN's hyena specialist group identifies the spotted hyena's negative reputation as detrimental to the species' continued survival, both in captivity and the wild.
Spotted hyena with cubs at den site
Taxonomy, origins and evolution
Unlike the striped hyena, for which a number of subspecies were proposed in light of its extensive modern range, the spotted hyena is a genuinely variable species, both temporally and spatially. Its range once encompassed almost all of Africa and Eurasia, and displayed a large degree of morphological geographic variation, which led to an equally extensive set of specific and subspecific epithets. It was gradually realised that all of this variation could be applied to individual differences in a single subspecies. In 1939, biologist L. Harrison Matthews demonstrated through comparisons between a large selection of spotted hyena skulls from Tanzania that all the variation seen in the then recognised subspecies could also be found in a single population, with the only set of characters standing out being pelage (which is subject to a high degree of individual variation) and size (which is subject to Bergmann's Rule). When fossils are taken into consideration, the species displayed even greater variation than it does in modern times, and a number of these named fossil species have since been classed as synonymous with Crocuta crocuta, with firm evidence of there being more than one species within the genus Crocuta still lacking.
Both Björn Kurtén and Camille Arambourg promoted an Asiatic origin for the species; Kurtén focussed his arguments on the Plio-Pleistocene taxon Crocuta sivalensis from the Siwaliks, a view defended by Arambourg, who nonetheless allowed the possibility of an Indo-Ethiopian origin. This stance was contested by Ficarelli and Torre, who referred to evidence of the spotted hyena's presence from African deposists dating from the early Pleistocene, a similar age to the Asian C. sivalensis. Studies on the phylogeographic distribution of mtDNA haplotypes indicates three migration events from Africa to Eurasia, though neither the topology of the phylogenetic tree or the fossil record exclude the possibility of an Asian origin. The earliest migration of spotted hyenas from Africa to Eurasia began less than 3.5 million years ago, most probably from the area where the first spotted hyena fossils were discovered, reaching East Asia and most likely also Pakistan. The second migration of spotted hyenas occurred less than 1.3–1.5 million years ago and resulted in the first arrival of hyenas in Europe and a separation of African spotted hyenas into a southern and a northern population. The third spotted hyena migration took place 0.36 million years ago, starting from the northern African population and reaching both Europe and Asia. Unlike other African carnivores, with the exception of the leopard, there is no evidence to suggest that spotted hyenas underwent a genetic bottleneck during the Pleistocene.
The ancestors of the genus Crocuta diverged from Hyaena (the genus of striped and brown hyenas) 10 million years ago. The ancestors of the spotted hyena probably developed social behaviours in response to increased pressure from other predators on carcasses, which forced them to operate in teams. At one point in their evolution, spotted hyenas developed sharp carnassials behind their crushing premolars; this rendered waiting for their prey to die no longer a necessity, as is the case for brown and striped hyenas, and thus became pack hunters as well as scavengers. They began forming increasingly larger territories, necessitated by the fact that their prey was often migratory, and long chases in a small territory would have caused them to encroach into another clan's land. It has been theorised that female dominance in spotted hyena clans could be an adaptation in order to successfully compete with males on kills, and thus ensure that enough milk is produced for their cubs. Another theory is that it is an adaptation to the length of time it takes for cubs to develop their massive skulls and jaws, thus necessitating greater attention and dominating behaviours from females. Its appearance in Europe and China during the Cromerian period coincided with the decline and eventual extinction of Pachycrocuta brevirostris, the giant short-faced hyena. As there is no evidence of environmental change being responsible, it is likely that the giant short-faced hyena became extinct due to competition with the spotted hyena.
Spotted hyena camera trap image
Physical description
The spotted hyena has a strong and well developed neck and forequarters, but relatively underdeveloped hindquarters. The rump is rounded rather than angular, which prevents attackers coming from behind from getting a firm grip on it. The head is wide and flat with a blunt muzzle and broad rhinarium. In contrast to the striped hyena, the ears of the spotted hyena are rounded rather than pointed. Each foot has four digits, which are webbed and armed with short, stout and blunt claws. The paw-pads are broad and very flat, with the whole undersurface of the foot around them being naked. The tail is relatively short, being 300–350 mm (12–14 in) long, and resembles a pompom in appearance. Unusually among hyaenids, and mammals in general, the female spotted hyena is considerably larger than the male. The spotted hyena has a proportionately large heart, constituting close to 1% of its body weight, thus giving it great endurance in long chases. In contrast, a lion's heart makes up only 0.45–0.57 percent of its body weight. The now extinct Eurasian populations were distinguished from the modern African populations by their shorter distal extremities and longer humerus and femur.
The skull of the spotted hyena differs from that of the striped hyena by its much greater size and narrower sagittal crest. For its size, the spotted hyena has one of the most powerfully built skulls among the Carnivora. The dentition is more dual purposed than that of other modern hyena species, which are mostly scavengers; the upper and lower third premolars are conical bone-crushers, with a third bone-holding cone jutting from the lower fourth premolar. The spotted hyena also has its carnassials situated behind its bone-crushing premolars, the position of which allows it to crush bone with its premolars without blunting the carnassials. Combined with large jaw muscles and a special vaulting to protect the skull against large forces, these characteristics give the spotted hyena a powerful bite which can exert a pressure of 80 kgf/cm² (1140 lbf/in²), which is 40% more pressure than a leopard can generate. The jaws of the spotted hyena outmatch those of the brown bear in bonecrushing ability, and free ranging hyenas have been observed to crack open the long bones of giraffes measuring 7 cm in diameter.
Size
The spotted hyena is the largest extant member of the Hyaenidae. Adults measure 95–165.8 cm (37.4–65.3 in) in body length, and have a shoulder height of 70–91.5 cm (27.6–36.0 in). Adult male spotted hyenas in the Serengeti weigh 40.5—55.0 kg (89—121 lb), while females weigh 44.5—63.9 kg (98—141 lb). Spotted hyenas in Zambia tend to be heavier, with males weighing on average 67.6 kg (149 lb), and females 69.2 kg (153 lb). Exceptionally large weights of 81.7 kg (180 lb)1 and 90 kg (200 lb) are known. It has been estimated that adult members of the now extinct Eurasian populations weighed 102 kg (225 lbs).
Fur
Fur colour varies greatly and changes with age. Unlike the fur of the striped and brown hyena, that of the spotted hyena consists of spots rather than stripes and is much shorter, lacking the well defined spinal mane of the former two species. The base colour generally is a pale greyish-brown or yellowish-grey on which an irregular pattern of roundish spots is superimposed on the back and hind quarters. The spots, which are of variable distinction, may be reddish, deep brown or almost blackish. The spots vary in size, even on single individuals, but are commonly 20 mm (0.79 in) in diameter. A less distinct spot pattern is present on the legs and belly but not on the throat and chest. A set of five, pale and barely distinct bands replace the spots on the back and sides of the neck. A broad, medial band is present on the back of the neck, and is lengthened into a forward facing crest. The crest is mostly reddish-brown in colour. The crown and upper part of the face is brownish, save for a white band above both eyes, though the front of the eyes, the area around the rhinarium, the lips and the back portion of the chin are all blackish. The limbs are spotted, though the feet vary in colour, from light brown to blackish. The fur is relatively sparse and consists of two hair types; moderately fine underfur (measuring 15–20 mm (0.59–0.79 in)) and long, stout bristle hairs (30–40 mm (1.2–1.6 in)). European Paleolithic rock art depicting the species indicates that the Eurasian populations retained the spots of their modern-day African counterparts.
Behaviour
The spotted hyena is a social animal which lives in large communities called "clans", which can consist of up to 80 individuals. Group-size varies geographically; in the Serengeti, where prey is migratory, clans are smaller than those in the Ngorongoro Crater, where prey is sedentary. Spotted hyena clans are more compact and unified than wolf packs, but are not as closely knit as those of African wild dogs. Females dominate males, with even the lowest ranking females being dominant over the highest ranking males. It is typical for females to remain with their natal clan, thus large clans usually contain several matrilines, whereas males typically disperse from their natal clan at the age of 2½ years. The clan is a fission-fusion society, in which clan-members do not often remain together, but may forage alone or in small groups. High-ranking hyenas maintain their position through aggression directed against lower-ranking clan-members. Spotted hyena hierarchy is nepotistic; the offspring of dominant females automatically outrank adult females subordinate to their mother. However, rank in spotted hyena cubs is greatly dependent on the presence of the mother; low-ranking adults may act aggressively toward higher-ranking cubs when the mother is absent. Although individual spotted hyenas only care for their own young, and males take no part in raising their young, cubs are able to identify relatives as distantly related as great-aunts. Also, males associate more closely with their own daughters rather than unrelated cubs, and the latter favour their fathers by acting less aggressively toward them.
Spotted hyena societies are more complex than those of other carnivorous mammals, and are remarkably similar to those of cercopithecine primates in respect to group size, structure, competition and cooperation. Like cercopithecine primates, spotted hyenas use multiple sensory modalities, recognise individual conspecifics, are conscious that some clan-mates may be more reliable than others, recognise 3rd party kin and rank relationships among clan-mates, and adaptively use this knowledge during social decision making. Also, like cercopithecine primates, dominance ranks in hyena societies are not correlated with size or aggression, but with ally networks. In this latter trait, the spotted hyena further show parallels with primates by acquiring rank through coalition. However, rank reversals and overthrows in spotted hyena clans are very rare.
Territory size is highly variable, ranging from less than 40 km² in the Ngorongoro Crater to over 1,000 km² in the Kalahari. Home ranges are defended through vocal displays, scent marking and boundary patrols. Clans mark their territories by either pasting or pawing in special latrines located on clan range boundaries. Clan boundaries are usually respected; hyenas chasing prey have been observed to stop dead in their tracks once their prey crosses into another clan's range. Hyenas will however ignore clan boundaries in times of food shortage. Males are more likely to enter another clan's territory than females are, as they are less attached to their natal group and will leave it when in search of a mate. Hyenas travelling in another clan's home range typically exhibit bodily postures associated with fear, particularly when meeting other hyenas. An intruder can be accepted into another clan after a long period of time if it persists in wandering into the clan's territory, dens or kills.
Denning behaviour
The clan's social life revolves around a communal den. While some clans may use particular den sites for years, others may use several different dens within a year or several den sites simultaneously. Spotted hyena dens can have more than a dozen entrances, and are mostly located on flat ground. The tunnels are usually oval in section, being wider than they are high, and narrow down from an entrance width of ½–1 metre (1.6–7.7 ft) to as small as 25 cm (9.8 in). In the rocky areas of East Africa and Congo, spotted hyenas use caves as dens, while those in the Serengeti use kopjes as resting areas in daylight hours. Dens have large bare patches around their entrances, where hyenas move or lie down on. Because of their size, adult hyenas are incapable of using the full extent of their burrows, as most tunnels are dug by cubs or smaller animals. The structure of the den, consisting of small underground channels, is likely an effective anti-predator device which protects cubs from predation during the absence of the mother. Spotted hyenas rarely dig their own dens, having been observed for the most part to use the abandoned burrows of warthogs, springhares and jackals. Dens are used mostly by several females at once, and it is not uncommon to see up to 20 cubs at a single site. The general form of a spotted hyena den is tunnel-shaped, with a spacious end chamber used for sleeping or breeding. This chamber measures up to 2 metres (6.6 ft) in width, the height being rather less. Females generally give birth at the communal den or a private birth den. The latter is primarily used by low status females in order to maintain continual access to their cubs, as well as ensure that they become acquainted with their cubs before transferral to the communal den.
Intelligence
Compared to other hyenas, the spotted hyena shows a greater relative amount of frontal cortex which is involved in the mediation of social behavior. Studies strongly suggest convergent evolution in spotted hyena and primate intelligence. A study done by evolutionary anthropologists demonstrated that spotted hyenas outperform chimpanzees on cooperative problem-solving tests; captive pairs of spotted hyenas were challenged to tug two ropes in unison to earn a food reward, successfully cooperating and learning the maneuvers quickly without prior training. Experienced hyenas even helped inexperienced clan-mates to solve the problem. In contrast, chimps and other primates often require extensive training, and cooperation between individuals is not always as easy for them. The intelligence of the spotted hyena was attested to by Dutch colonists in 19th century South Africa, who noted that hyenas were exceedingly cunning and suspicious, particularly after successfully escaping from traps. Spotted hyenas seem to plan on hunting specific species in advance; hyenas have been observed to indulge in activities such as scent marking before setting off to hunt zebras, a behaviour which does not occur when they target other prey species. Also, spotted hyenas have been recorded to utilise deceptive behaviour, including giving alarm calls during feeding when no enemies are present, thus frightening off other hyenas and allowing them to temporarily eat in peace. Similarly, mothers will emit alarm calls in attempting to interrupt attacks on their cubs by other hyenas.
Hunting behaviour
Unlike other large African carnivores, spotted hyenas do not preferentially prey on any species, and only buffalo and giraffe are significantly avoided. Spotted hyenas prefer prey with a body mass range of 56–182 kg (123.5–401 lb), with a mode of 102 kg (224.9 lb). When hunting medium to large sized prey, spotted hyenas tend to select certain categories of animal; young animals are frequently targeted, as are old ones, though the latter category is not so significant when hunting zebras, due to their aggressive antipredator behaviours. The spotted hyena tracks live prey by sight, hearing and smell. Carrion is detected by smell and the sound of other predators feeding. During daylight hours, it watches vultures descending upon carcasses. Its auditory perception is powerful enough for it to detect sounds of predators killing prey or feeding on carcasses over distances of up to 10 km (6 mi). Unlike the grey wolf, the spotted hyena relies more on sight than smell when hunting, and does not follow its prey's prints or travel in single file. Small prey is killed by being shaken in the mouth, while large prey is eaten alive.
Spotted hyenas usually hunt wildebeest either singly, or in groups of two or three. They catch adult wildebeest usually after 5 km (3 mi) chases at speeds of up to 60 km/h (37 mi/h). Chases are usually initiated by one hyena and, with the exception of cows with calves, there is little active defense from the wildebeest herd. Wildebeest will sometimes attempt to escape hyenas by taking to water though, in such cases, the hyenas almost invariably catch them. Zebras require different hunting methods to those used for wildebeest, due to their habit of running in tight groups and aggressive defence from stallions. Typical zebra hunting groups consist of 10–25 hyenas, though there is one record of a hyena killing an adult zebra unaided. During a chase, zebras typically move in tight bunches, with the hyenas pursuing behind in a crescent formation. Chases are usually relatively slow, with an average speed of 15–30 km/h. A stallion will attempt to place himself between the hyenas and the herd, though once a zebra falls behind the protective formation it is immediately set upon, usually after a chase of 3 km (1.8 mi). Though hyenas may harass the stallion, they usually only concentrate on the herd and attempt to dodge the stallion's assaults. Unlike stallions, mares typically only react aggressively to hyenas when their foals are threatened. Unlike wildebeest, zebras rarely take to water when escaping hyenas. When hunting Thomson's gazelles, spotted hyenas usually operate alone, and prey primarily on young fawns. Chases against both adult and young gazelles can cover distances of 5 km (3 mi) with speeds of 60 km/h (37 mi/h). Female gazelles do not defend their fawns, though they may attempt to distract hyenas by feigning weakness.
Diet
The spotted hyena is very efficient at eating its prey; not only is it able to splinter and eat the largest ungulate bones, it is also able to digest them completely. Spotted hyenas can digest all organic components in bones, not just the marrow. They react to alighting vultures more readily than other African carnivores, and are more likely to stay in the vicinity of lion kills or human settlements.
Wildebeest are the most commonly taken medium sized ungulate prey item in both Ngorongoro and the Serengeti, with zebra and Thomson's gazelles coming close behind. Cape buffalo are rarely attacked due to differences in habitat preference, though adult bulls have been recorded to be taken on occasion. In Kruger National Park, blue wildebeest, cape buffalo, Burchell's zebra, greater kudu and impala are the spotted hyena's most important prey, while giraffe, impala, wildebeest and zebra are its major food sources in the nearby Timbavati area. Springbok and kudu are the main prey in Namibia's Etosha National Park, and springbok in the Namib. In the southern Kalahari, gemsbok, wildebeest and springbok are the principal prey. In Chobe, the spotted hyena's primary prey consists of migratory zebra and resident impala. In Kenya's Masai Mara, 80% of the spotted hyena's prey consists of topi and Thomson's gazelle, save for during the four-month period when zebra and wildebeest herds migrate to the area. Bushbuck, suni and buffalo are the dominant prey items in the Aberdare Mountains, while Grant's gazelle, gerenuk, sheep, goats and cattle are likely preyed upon in northern Kenya. In west Africa, it is thought that the spotted hyena is primarily a scavenger, but will occasionally attack domestic stock and medium-size antelopes in some areas. In Cameroon, it is common for spotted hyenas to feed on small antelopes like kob, but may also scavenge on reedbuck, kongoni, buffalo, giraffe, African elephant, topi and roan antelope carcasses. Records indicate that spotted hyenas in Malawi feed on medium to large-sized ungulates such as waterbuck and impala. In Tanzania's Selous Game Reserve, spotted hyenas primarily prey on wildebeest, followed by buffalo, zebra, impala, giraffe, reedbuck and kongoni. In Uganda, it is thought that the species primarily preys on birds and reptiles, while in Zambia it is primarily a scavenger.
Spotted hyenas have also been found to catch fish, tortoises, humans, black rhino, hippo calves, young African elephants, pangolins and pythons. There is at least one record of four hyenas killing an adult hippopotamus in Kruger National Park. The fossil record indicates that the now extinct European spotted hyenas primarily fed on Przewalski's horses, Irish elk, reindeer, red deer, roe deer, fallow deer, wild boar, ibex, steppe wisent, aurochs, and woolly rhinoceros. Spotted hyenas are thought to be responsible for the dis-articulation and destruction of some cave bear skeletons. Such large carcasses were an optimal food resource for hyenas, especially at the end of winter, when food was scarce. Spotted hyenas may consume leather articles such as boots and belts around campsites. Jane Goodall recorded spotted hyenas attacking or savagely playing with the exterior and interior fittings of cars, and the species is thought to be responsible for eating car tyres.
A single spotted hyena can eat at least 14.5 kg of meat per meal. Although spotted hyenas act aggressively toward each other when feeding, they compete with each other mostly through speed of eating, rather than by fighting as lions do. When feeding on an intact carcass, spotted hyenas will first consume the meat around the loins, then open the abdominal cavity and pull out the soft organs. Once the stomach, its wall and contents are consumed, the hyenas will eat the lungs and abdominal and leg muscles. Once the muscles have been eaten, the carcass is disassembled and the hyenas carry off pieces to eat in peace. Spotted hyenas are adept at eating their prey in water: they have been observed to dive under floating carcasses to take bites, then resurface to swallow. A single hyena can take less than two minutes in eating a gazelle fawn, while a group of 35 hyenas can completely consume an adult zebra in 36 minutes. Spotted hyenas do not require much water, and typically only spend 30 seconds drinking.
Enemies and competitors
In areas where spotted hyenas and lions are sympatric, the two species occupy the same ecological niche, and are thus in direct competition with one another. In some cases, the extent of dietary overlap can be as high as 68.8%. Lions typically ignore spotted hyenas, unless they are on a kill or are being harassed by them. There exists a common misconception that hyenas steal kills from lions, but most often it's the other way around. Lions will readily steal the kills of spotted hyenas; in the Ngorongoro Crater, it is common for lions to subsist largely on kills stolen from hyenas. Lions are quick to follow the calls of hyenas feeding, a fact demonstrated by field experiments, during which lions repeatedly approached whenever the tape-recorded calls of hyenas feeding were played. When confronted on a kill by lions, spotted hyenas will either leave or wait patiently at a distance of 30–100 metres until the lions have finished eating. In some cases, spotted hyenas are bold enough to feed alongside lions, and may occasionally force lions off a kill. This mostly occurs during the nighttime, when hyenas are bolder. Spotted hyenas usually prevail against groups of lionesses unaccompanied by males if they outnumber them 4:1. In some instances they were seen to have taken on and routed two pride males while outnumbering them 5:1. The two species may act aggressively toward one another even when there is no food at stake. Lions may charge at hyenas and maul them for no apparent reason; one male lion was filmed killing two hyenas on separate occasions without eating them, and lion predation can account for up to 71% of hyena deaths in Etosha. Spotted hyenas have adapted to this pressure by frequently mobbing lions which enter their territories. Experiments on captive spotted hyenas revealed that specimens with no prior experience with lions act indifferently to the sight of them, but will react fearfully to the scent.
Although cheetahs and leopards preferentially prey on smaller animals than those hunted by spotted hyenas, hyenas will steal their kills when the opportunity presents itself. Cheetahs are usually easily intimidated by hyenas, and put up little resistance, while leopards, particularly males, may stand up to hyenas. There are records of some male leopards preying on hyenas. Hyenas are nonetheless dangerous opponents for leopards; there is at least one record of a young adult male leopard dying from a septicemia infection caused by wounds inflicted by a spotted hyena.
Spotted hyenas will follow packs of African wild dogs in order to appropriate their kills. They will typically inspect areas where wild dogs have rested and eat any food remains they find. When approaching wild dogs at a kill, solitary hyenas will approach cautiously and attempt to take off with a piece of meat unnoticed, though they may be mobbed by the dogs in the attempt. When operating in groups, spotted hyenas are more successful in pirating dog kills, though the dog's greater tendency to assist each other puts them at an advantage against spotted hyenas, who rarely work in unison. Cases of dogs scavenging from spotted hyenas are rare. Although wild dog packs can easily repel solitary hyenas, on the whole, the relationship between the two species is a one sided benefit for the hyenas, with wild dog densities being negatively correlated with high hyena populations.
Spotted hyenas dominate other hyena species wherever their ranges overlap. Brown hyenas encounter spotted hyenas in the Kalahari, where the brown species outnumbers the spotted. The two species typically encounter each other on carcasses, which the larger spotted species usually appropriate. Sometimes, brown hyenas will stand their ground and raise their manes while emitting growls. This usually has the effect of seemingly confusing spotted hyenas, which will act bewildered, though they will occasionally attack and maul their smaller cousins. Similar interactions have been recorded between spotted and striped hyenas in the Serengeti.
Jackals will feed alongside hyenas, though they will be chased if they approach too closely. Spotted hyenas will sometimes follow jackals during the gazelle fawning season, as jackals are effective at tracking and catching young animals. Hyenas do not take to eating jackal flesh readily; four hyenas were reported to take half an hour in eating a golden jackal. Overall, the two animals typically ignore each other when there is no food or young at stake.
Spotted hyenas usually keep a safe distance from Nile crocodiles. Though they readily take to water to catch and store prey, hyenas will avoid crocodile infested waters.
Body language
Spotted hyenas have a complex set of postures in communication. When afraid, the ears are folded flat, and are often combined with baring of the teeth and a flattening of the mane. When attacked by other hyenas or by wild dogs, the hyena lowers its hindquarters. Before and during an assertive attack, the head is held high with the ears cocked, mouth closed, mane erect and the hindquarters high. The tail usually hangs down when neutral, though it will change position according to the situation. When a high tendency to flee an attacker is apparent, the tail is curled below the belly. During an attack, or when excited, the tail is carried forward on the back. An erect tail does not always accompany a hostile encounter, as it has also been observed to occur when a harmless social interaction occurs. Although they do not wag their tails, spotted hyenas will flick their tails when approaching dominant animals or when there is a slight tendency to flee. When approaching a dominant animal, subordinate spotted hyenas will walk on the knees of their forelegs in submission. Greeting ceremonies among clan-members consist of two individuals standing parallel to each other and facing opposite directions.
The spotted hyena has an extensive vocal range, with sounds ranging from whoops, fast whoops, grunts, groans, lows, giggles, yells, growls, soft grunt-laughs, loud grunt-laughs, whines and soft squeals. The loud "who-oop" call, along with the maniacal laughter, are among the most recognisable sounds of Africa. Typically, very high-pitched calls indicate fear or submission, while loud, lower-pitched calls express aggression. The pitch of the laugh indicates the hyena's age, while variations in the frequency of notes used when hyenas make noises convey information about the animal's social rank.
Range, habitat and population
The spotted hyena's distribution once ranged in Europe from the Iberian Peninsula to the Urals, where it remained for at least one million years. Remains have also been found in the Russian Far East, and it has been theorised that the presence of hyenas there may have delayed the colonisation of North America. The causes of the species' extinction in Eurasia are still largely unknown. In Western Europe at least, the spotted hyena's extinction coincided with a decline in grasslands 12,500 years ago. Europe experienced a massive loss of lowland habitats favoured by spotted hyenas, and a corresponding increase in mixed woodlands. Spotted hyenas, under these circumstances, would have been outcompeted by wolves and humans which were as much at home in forests as in open lands, and in highlands as in lowlands. Spotted hyena populations began to shrink roughly 20,000 years ago, completely disappearing from Western Europe between 14–11,000 years ago, and earlier in some areas.
Historically, the spotted hyena was widespread throughout Sub-Saharan Africa. It is present in all habitats save for the most extreme desert conditions, tropical rainforests and the top of alpine mountains. Its current distribution is patchy in many places, especially in West Africa. Populations are concentrated in protected areas and surrounding land. There is a continuous distribution over large areas of Ethiopia, Kenya, Tanzania, Botswana, Namibia and the Transvaal Lowveld areas of South Africa.
The species dwells in semi-deserts, savannah, open woodland, dense dry woodland, and mountainous forests up to 4,000m in altitude. It is scarce or absent in tropical rainforests and coastal areas. Its preferred habitats in west Africa include the Guinea and Sudan savannahs, and is absent in the belt of dense coastal forest. In the Namib Desert, it occurs in riverine growth along seasonal rivers, the sub-desertic pro-Namib and the adjoining inland plateau. In ideal habitats, the spotted hyena outnumbers other large carnivores, including other hyena species. However, the striped and brown hyena occur at greater densities than the spotted species in desert and semi-desert regions. Population densities based on systematic censuses vary substantially, from 0.006 to 1.7 individuals per km².
Attacks on humans
As with most mammalian predators, the spotted hyena is typically shy in the presence of humans, and has the highest flight distance (up to 300 metres) among African carnivores. However, this distance is reduced during the night, when hyenas are known to follow people closely. Although spotted hyenas do prey on humans in modern times, such incidences are rare. However, attacks on humans by spotted hyenas are likely to be underreported. Man-eating spotted hyenas tend to be very large specimens; a pair of man-eating hyenas, responsible for killing 27 people in Mlanje, Malawi in 1962 and were weighed at 72 kg (159 lb) and 77 kg (170 lb) after being shot. Victims of spotted hyenas tend to be women, children and sick or infirm men, and there are numerous cases of biologists in Africa being forced up trees in order to escape them. Attacks occur most commonly in September, when many people sleep outdoors, and bush fires make the hunting of wild game difficult for hyenas.
In 1903, Hector Duff wrote of how spotted hyenas in the Mzimba district of Angoniland would wait at dawn outside people's huts and attack them when they opened their doors. In 1908–09 in Uganda, spotted hyenas regularly killed sufferers of African sleeping sickness as they slept outside in camps. Spotted hyenas are widely feared in Malawi, where they have been known to occasionally attack people at night, particularly during the hot season when people sleep outside. Hyena attacks were widely reported in Malawi's Phalombe plain, to the north of Michesi Mountain. Five deaths were recorded in 1956, five in 1957 and six in 1958. This pattern continued until 1961 when eight people were killed. During the 1960s, Flying Doctors received over two dozen cases of hyena attacks on humans in Kenya. An anecdotal 2004 news report from the World Wide Fund for Nature indicates that 35 people were killed by spotted hyenas during a 12 month period in Mozambique along a 20 km stretch of road near the Tanzanian border.
Although attacks against living humans are rare, the spotted hyena readily feeds on human corpses. In the tradition of the Maasai and the Hadza, corpses are left in the open for spotted hyenas to eat. A corpse rejected by hyenas is seen as having something wrong with it, and liable to cause social disgrace, therefore it is not uncommon for bodies to be covered in fat and blood from a slaughtered ox. In Ethiopia, hyenas were reported to feed extensively on the corpses of victims of the 1960 attempted coup and the Red Terror. Hyenas habituated to scavenging on human corpses may develop bold behaviours towards living people; hyena attacks on people in southern Sudan increased during the Second Sudanese Civil War, when human corpses were readily available to them.
Urban hyenas
In some parts of Africa, spotted hyenas have begun to frequent metropolitan areas, where groups or "clans" of the animals have become a menace. The Ethiopian capital Addis Ababa is estimated to have up to a thousand resident hyenas which survive by scavenging rubbish tips and predating feral dogs and cats. There have also been attacks on humans living rough. In 2013 a baby boy was killed by hyenas after being snatched from his mother as she camped near the Hilton Hotel. Some 40 of the animals were reportedly seen alongside a fence bordering the British Embassy compound. In December 2013 a cull was organised and marksmen killed ten hyenas which had occupied wasteland near the city centre.
Spotted hyenas in captivity
From a husbandry point of view, hyenas are easily kept, as they have few disease problems and it is not uncommon for captive hyenas to reach 15–20 years of age. Nevertheless, the spotted hyena was historically scantily represented in zoos, and was typically obtained in order to fill empty cages until a more prestigious species could be obtained. In subsequent years, animals considered to be more charismatic were allocated larger and better quality facilities, while hyenas were often relegated to inferior exhibits. In modern times, the species faces spatial competition from more popular animals, especially large canids. Also, many captive individuals have not been closely examined to confirm their sexes, thus resulting in non-breeding pairs often turning out to be same-sexed individuals. As a result, many captive hyena populations are facing extinction.
During the 19th century, the species was frequently displayed in travelling circuses as oddities. Alfred Brehm wrote that the spotted hyena is harder to tame than the striped hyena, and that performing specimens in circuses were not up to standard. Sir John Barrow described how spotted hyenas in Sneeuberge were trained to hunt game, writing that they were "as faithful and diligent as any of the common domestic dogs". In Tanzania, spotted hyena cubs may be taken from a communal den by witchdoctors, in order to increase their social status. An April 2004 BBC article described how a shepherd living in the small town of Qabri Bayah about 50 kilometres from Jigjiga, Ethiopia managed to use a male spotted hyena as a livestock guardian dog, suppressing its urge to leave and find a mate by feeding it special herbs. If not raised with adult members of their kind, captive spotted hyenas will exhibit scent marking behaviours much later in life than wild specimens. Although easily tamed, spotted hyenas are exceedingly difficult to house train, and can be very destructive; a captive, otherwise perfectly tame, specimen in the Tower of London managed to tear an 8-foot (2.4 m) long plank nailed to its recently repaired enclosure floor with no apparent effort. During the research leading to the composition of his monograph The Spotted Hyena: A Study of Predation and Social Behavior, Hans Kruuk kept a tame hyena he named Solomon. Kruuk found Solomon's company so congenial, he would have kept him, but Solomon had an insatiable taste for "cheese in the bar of the tourist lounge and bacon off the Chief Park Warden's breakfast table," and no door could hold him back, so Solomon was obliged to live out his days in the Edinburgh Zoo.
South African zoologist with captive spotted hyenas