HYENA

Facts

Spotted Hyena

The Spotted Hyena (Crocuta Crocuta), also known as the laughing Hyena, is a Hyena species, currently classed as the sole extant member of the genus Crocuta, native to sub-Saharan Africa. The spotted Hyena is the largest extant member of the Hyaenidae, and is further physically distinguished from other species by its vaguely bear-like build, rounded ears, less prominent mane, spotted pelt, more dual-purposed dentition, fewer nipples and pseudo-penis.

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 Baboons and Macques 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 Hyena often run through ungulate herds to select an individual to attack. Once selected, their prey is chased over a long distance, often several kilometres, at speeds of up to 60 kilometres per hour (37 mph).

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 have short, stout and blunt claws. The paw-pads are broad and 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. For its size, the Spotted Hyena has one of the most powerfully built skull 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 carnassial situated behind its bone-crushing premolars, the position of which allows it to crush bone with its premolars without blunting the carnassial. 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 kgs/cm2 (1140 lbs/in2) which is 40% more force than a Leopard can generate. The jaws of the Spotted Hyena outmatch those of the Brown Bear in bone-crushing ability and free ranging.

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). 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).

Spotted Hyena are social animals that live in large communities (referred to as “clans”) which can consist of at most 80 individuals. Group-size varies geographically; Spotted Hyena clans are more compact and unified than wolf packs, but are not as closely knit as those of African Wild Dog.

Females usually dominate males, including in cases where low-ranking females generally dominate over high-ranking males, but they will also occasionally co-dominate with a male. Cubs take the rank directly below their mothers at birth. So when the matriarch passes away, their youngest female cub will take over as matriarch. 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.

The Spotted Hyena is a non-seasonal breeder, though a birth peak does occur during the wet season. Females are poly oestrous, with an oestrus period lasting two weeks. Like many feliform species, the Spotted Hyena is promiscuous and no enduring pair bonds are formed. Members of both sexes may copulate with several mates over the course of several years. Males will show submissive behaviour when approaching females in heat, even if the male outweighs his partner. Females usually favour younger males born or joined into the clan after they were born. Older females show a similar preference, with the addition of preferring males with whom they have had long and friendly prior relationships. Passive males tend to have greater success in courting females than aggressive ones. Copulation in Spotted Hyena is a relatively short affair, lasting 4–12 minutes, and typically only occurs at night with no other Hyena present. Copulation may be repeated multiple times during a period of several hours. The length of the gestation period tends to vary greatly, but the average length is 110 days. The average litter consists of two cubs, with three occasionally being reported. Giving birth is difficult for female Hyena, as the females give birth through their narrow clitoris, and Spotted Hyena cubs are the largest carnivore young relative to their mothers’ weight. Cubs are born with soft, dark brown hair, and weigh 1.5 kg on average. Unique among carnivorous mammals, Spotted Hyena are also born with their eyes open and with 6–7 mm long canine teeth and 4 mm long incisors. Also, cubs will attack each other shortly after birth. Lactating females can carry 3–4 kg (6.6–8.8 lb) of milk in their udders. Spotted Hyena milk has the highest protein and fat content of any terrestrial carnivore. Cubs will nurse from their mother for 12–16 months, though they can process solid food as early as three months. Within ten days of birth, they are able to move at considerable speed. Cubs begin to lose the black coat and develop the spotted, lighter coloured pelage of the adults at 2–3 months. They begin to exhibit hunting behaviours at the age of eight months, and will begin fully participating in group hunts after their first year. Spotted Hyena reach sexual maturity at the age of three years. The average lifespan in zoos is 12 years, with a maximum of 25 years.

Brown Hyena

Brown Hyena have a social hierarchy comparable to that of wolves, with a mated pair and their offspring. They live in clans composed of extended families of four to six individuals. Clans defend their territory and all members cooperate in raising cubs. Territories are marked by ‘pasting’, during which the Hyena deposits secretions from its large anal gland, which is located below the base of the tail and produces a black and white paste, on vegetation and boulders. Brown Hyena maintain a stable clan hierarchy through ritualised aggressive displays and mock fights. A Brown Hyena male can move up in rank by killing a higher ranking male in confrontation, while the alpha female is usually just the oldest female in the clan. Emigration is common in Brown Hyena clans, particularly among young males, which will join other groups upon reaching adulthood.

Brown Hyena are primarily scavengers the bulk of whose diet consists of carcasses killed by larger predators, but they may supplement their diet with rodents, insects, eggs, fruit and fungi (the desert truffle Kalaharituber Pfeilii). As they are poor hunters, live prey makes up only a small proportion of their diet. They have an exceptional sense of smell and can locate carcasses kilometres away.

The Brown Hyena does not have a mating season. Female Brown Hyena are poly oestrus and typically produce their first litter when they are two years old. They mate primarily from May to August. Males and females in the same clan usually do not mate with each other, rather females will mate with nomadic males. Clan males display no resistance to this behaviour, and will assist the females in raising their cubs. Females give birth in dens, which are hidden in remote sand dunes far from the territories of Spotted Hyena and Lion. The gestation period is around 3 months. Mothers generally produce one litter every 20 months. Usually, only the dominant female breeds, but if two litters are born in the same clan, the mothers will nurse each other’s cubs, though favouring their own. Litters usually consist of 1–5 cubs, which weigh 1 kg (2.2 lb) at birth. Unlike Spotted Hyena, Brown Hyena are born with their eyes closed, and open them after eight days. Cubs are weaned at 12 months and leave their dens after 18 months. Also unlike Spotted Hyena, all adult members of the clan will carry food back to the cubs. They are not fully weaned and do not leave the vicinity of their den until they reach 14 months of age. Brown Hyena reach full size at an age of around 30 months and have a life span of about 12 to 15 years.