|The spotted hyaena is named for its spotted coat and is known as the laughing hyaena because of its giggling cry. Although thought to be just a scavenger, this African carnivore is an effective endurance hunter. It lives in clans of 3-80 in which females are dominant and masculinated.|
The spotted hyaena is strongly built with a massive neck and large head. The jaws are probably the strongest in relation to size of any mammal. Unlike other hyaenas, the spotted hyaena has rounded ears and unlike the aardwolf (Proteles cristata) which has five toes, the spotted hyaena has four digits on each foot with short, non-retractable claws and broad toe pads.
The spotted hyaena is strongly built with a massive neck and large head. The front legs are longer than the hind legs, which gives the back of the hyaena a slightly odd, downward slope. The hyaena’s relatively short hind legs and long neck are perfect adaptations to the loping locomotion because they minimize its energetic costs. Its long, muscular neck further enables it to carry heavy prey away from other hyaenas and lions (Panthera leo), or to bring food to their cubs at the communal den.
The spotted hyaena has a very course and wooly coat that is sandy, yellowish, or gray in color. The species is named for the black or dark brown spots that cover most of the body. These spots are darkest in younger animals and can be almost completely absent in very old animals.
The body length of the spotted hyaena from head to tail is about 95 to 150 centimeters (37-59 inches) and the height at the shoulder is reported from about 75 to 85 centimeters (29-33 inches). The tail is about 30 to 36 centimeters (11-14 inches) long and ends in a bushy black tip. About two-thirds of the tail is composed of bone with the other one-third being solely hair.
The spotted hyaena is sexually dimorphic with females weighing around 6.6 kilograms more than males. Male weight ranges from about 45 to 60 kilograms (154-132 pounds) whereas females weigh 55 to over 70 kilograms (121-154 pounds).
Female spotted hyaenas are extremely masculinated and the genitalia of females are almost indistinguishable from those of males. Thus, males and females look extremely similar. The clitoris is enlarged, looks like a penis, and is capable of erection. Females also have a pair of sacs in the genital region which are filled with fibrous tissue. These look much like a scrotum, but are covered with more hair than the male’s scrotum. The female has no external vagina and must urinate, mate, and deliver young through the urogenital canal that exits through the pseudo-penis. High androgen levels were once thought to be a major cause of this masculinazation. One current hypothesis is that sexual mimicry is the driving force behind hyaena masculinization as females that look like males may be protected from aggression from other females.
The spotted hyaena is named for the black or dark brown spots that cover most of the body. These spots are darkest in younger animals and can be almost completely absent in very old animals.
The spotted hyaena is sometimes referred to as the laughing hyaena because of its trademark giggling call. This cackling sound is associated with fear or excitement and is often given when an individual is being chased.
The spotted hyena’s scientific name Crocuta crocuta, was once widely thought to be derived from the Latin loanword crocutus, which translates as saffron-coloured one, in reference to the animal’s fur color. This was proven to be incorrect, as the correct spelling of the loanword would have been Crocāta, and the word was never used in that sense by Graeco-Roman sources. Crocuta actually comes from the Ancient Greek word Κροκόττας (Krokottas), which is derived from the Sanskrit koṭṭhâraka, which in turn originates from kroshṭuka (both of which were originally meant to signify the golden jackal). The earliest recorded mention of Κροκόττας is from Strabo’s Geographica, where the animal is described as a mix of wolf and dog native to Ethiopia.
The spotted hyaena is the largest of the four extant hyenas in the Hyaenidae family. Other species include the aardwolf (Proteles cristata), the brown hyaena (Brunnea hyaena), and the striped hyaena (Hyaena hyaena).
The spotted hyaena is currently classed as the sole extant member of the genus Crocuta.
Unlike other hyaenas, the spotted hyaena has rounded ears and unlike the aardwolf which has five toes, the spotted hyaena has four digits on each foot with short, non-retractable claws and broad toe pads.
Until very recently, spotted hyaenas were a common species in most of sub-Saharan Africa. Through the end of the Pleistocene, spotted hyaenas ranged throughout Eurasia. The reasons for the hyaena’s extinction there are not certain.
Today, spotted hyaenas are endemic to sub-Saharan Africa, south of the Sahara, and are relatively widely distributed. Their current distribution is patchy, especially in West and Central Africa, with populations often concentrated in protected areas. High densities occur in the Serengeti and especially the Ngorongoro crater in Tanzania.
More continuous distributions persist over large areas of Chad, Central African Republic, South Sudan, Ethiopia, Kenya, Tanzania, Botswana, Angola, Namibia, and parts of South Africa. Since 1970, spotted hyaenas have been reported to still be widespread in Djibouti and Gambia. Long-term studies on spotted hyaenas and recent surveys have confirmed their presence in Benin, Botswana, Burkina Faso, Central African Republic, Ethiopia, Ghana, Côte d’Ivoire, Kenya, Malawi, Namibia, Niger, Nigeria, The Republic of Congo, Senegal, South Africa, Tanzania, Zambia, Zimbabwe.
In Eritrea, spotted hyaenas have not or only very rarely been sighted until 2007, but they are now regularly sighted throughout the country. It is thus likely that spotted hyaenas established a small population in Eritrea. Spotted hyaenas may occasionally enter Gabon from The Republic of Congo but there is no evidence to suggest that there is a resident population in Gabon.
The species has been reported as extinct in Algeria where they may have occurred in the Ahaggar and Tassili d’Ajjer. There is also no confirmed evidence of
their occurrence in Egypt, Lesotho, Liberia, Libya, Tunisia, or Morocco, and no recent records from Togo.
Only occasional animals are seen in the forests of Mount Kenya as they have been extirpated from most areas of South Africa.
The spotted hyaena is the most numerous large predator in the Serengeti. Viable populations of spotted hyaena exist in a number of countries and a tentative estimate of the total global population is between 27,000 and 47,000.
The largest known populations occur in the Serengeti ecosystem in Tanzania, Kenya, and South Africa with 7,200-7,700 hyaenas in the Tanzanian sector and 500-1,000 hyaenas in the Kenyan sector. There are 1,300-3,900 hyaenas in Kruger National Park in South Africa.
Population densities based on systematic censuses vary substantially, from 0.006 individuals per square kilometers in Namibia to 2.4 individuals per square kilometers in the Ngorongoro Crater in Tanzania . Low population densities occur in semi-desert areas in southern Africa (0.006-0.05 individuals per square kilometers), such as the Namib and Etosha Pan. High densities occur in savanna and some open woodlands in Tanzania and Kenya, as well as in montane forests (0.32-2.4 individuals square kilometers), such as Selous Game Reserve, Aberdare National Park, and Ngorongoro Crater. Most populations in protected areas in southern Africa and several populations in eastern Africa are considered to be stable.
There is evidence that a few populations have increased during the past years. In Eritrea, there were no confirmed records of the species until the 1990s, but since then, spotted hyaenas have been recorded throughout the country and the population is believed to be increasing. Similarly, in Chad, the population of the largest national park has experienced a two-fold increase during the last few years. In contrast, many populations in eastern, central, and western Africa, are considered to be declining, even in protected areas, mostly due to an increase in human-wildlife conflict during which humans poison and cull spotted hyaenas, and due to incidental snaring. In Gabon, substantial efforts to find spotted hyenas revealed that single individuals from The Republic of Congo may enter Gabon from time to time, but there is no evidence of a resident population in Gabon.
Spotted hyaenas are present in all habitats including semi-desert, savanna, open woodland, dense dry woodland, acacia bush, and even montane forest habitats, such as in the Aberdares, Mt Kenya, and the Ethiopian Highlands, up to a 4,100 meter altitude. In west Africa, the species prefers the Guinea and Sudan savannas.
It is absent from, or present at very low densities in extreme desert conditions, the highest altitudes on mountains, and tropical rainforests, although they may make deep incursions into forested areas where logging roads provide access. The species becomes increasingly less common in dense forested habitat and is less common than the striped hyaena (Hyaena hyaena) and the brown hyaena (Hyaena brunnea) in desert habitats. They do not inhabit the coastal tropical rainforest of west or central Africa.
In many parts of their range, they occur in close association with human habitations.
Central African Republic
Spotted hyaenas forms social groups called clans, composed of 3 to 80 members. Larger clans generally occur in prime territory with large prey concentrations, such as the Ngorongoro crater, whereas smaller clans occur in desert areas in southern Africa. Although spotted hyaenas live in clans, the members of a clan are only observed all together at kills, when defending the territory, or at a communal den. More often, the clan members forage alone or in small groups.
Communal denning seems to be an important part of spotted hyaena social behavior, but no communal care of young takes place. One exception to this has been observed in the Kalahari during a particularly difficult period.
Spotted hyaena territory size is extremely variable ranging from as small as 40 square kilometeres in the Ngorongoro crater to 1000 square kilometers in the Kalahari. Spotted hyaena clans defend group territories using vocal displays and scent marking. Scent marks are deposited from a secretion of the anal gland and from a secretion of glands on the feet. In addition, spotted hyaenas use communal latrines which also serve to mark territory boundaries. Chemical communication occurs because of the use of common latrine areas, as well as in scent marking.
Spotted hyaena clans are matrilinear and females are usually dominant over males. Higher ranking females have been shown to associate more with kin than low-ranking females. This behavior is beneficial to related females because they forage together and engage in coalitionary attacks against unrelated females when competing for food at a kill. Thus, females who associate with their female kin are able to gather larger amounts of food more efficiently.
In addition to allowing matrilines to defend their rank, close associations among female kin allow some of these kin groups to displace higher ranking matrilines under certain conditions. Finally, low-ranking females preferentially associate with higher ranking females. It is hypothesized that these low-ranking females receive benefits from high-ranking females through reciprocal cooperation.
Female spotted hyaenas remain in their natal clan for their entire lives and have stable linear dominance hierarchies. In addition, rank is inherited from the mother so these hierarchies remain stable for many generations. Males, however, disperse upon reaching sexual maturity. Juvenile males emigrate after puberty and join new clans where their position in the dominance hierarchy may increase over time. Once a male joins another clan, he enters a dominance queue that the other males respect. As more males enter the queue and older males die, the male will move up through the social rank. Males spend a long time developing relationships with females in the clan. They follow females for periods of days or weeks and eventually gain favor with the females through this behavior.
Spotted hyaenas utilize tactile communication between mothers and their young, rival young, and mates, and in a genital investigation greeting.
Spotted hyaenas perform a phallic inspection as a greeting. Two individuals stand head to tail, lift the rear leg closest to the other and then sniff and touch each other’s extended phallus for up to 30 seconds. Females usually do not greet males in this manner, and if they do it is usually only the highest ranking males. Cubs can perform this ritual within the first month of life.
The spotted hyaena is well known for the wide variety of vocal communication used. Groans and soft squeals are emitted during hyaena greetings. A whoop is used as a contact call in addition to a fast whoop which is used by excited hyaenas at a kill. Males give the fast whoop more often than females but are generally ignored. Female calls generally elicit much more of a reaction. Finally, a lowing call is used by impatient hyaenas who are kept waiting at a kill.
Spotted hyaenas also give several calls related to aggression. These include grunting, giggling, growling, yelling, and a rattling growl. These calls are given in various aggressive interactions with clan members, other clans, or other species.
The giggling is the trademark laughing call of the hyaena. This call is associated with fear or excitement and is often given when an individual is being chased. Because of this cackling sound, the species is sometimes referred to as the laughing hyaena.
Spotted hyaenas have a reputation for being mostly scavengers, but are, in fact, effective and flexible hunters. A study in the Kalahari found that 70% of the diet was composed of direct kills.
The spotted hyaena uses its keen senses of sight, hearing, and smell to hunt live prey and to detect carrion from afar. Typically, clans split up into hunting groups of two to five individuals, although zebra are hunted in larger groups.
The spotted hyaena is an endurance hunter and can run or lope over great distances in search for prey. They often chase their prey long distances at speeds up to 60 kilometers per hour. A chase in the Kalahari once lasted 24 kilometers before the prey, a common eland (Tragelaphus oryx), was captured. The spotted hyaena is strongly built with a massive neck and large head. The front legs are longer than the hind legs, which gives the back of the hyaena a slightly odd, downward slope. The hyaena’s relatively short hind legs and long neck are perfect adaptations to the loping locomotion because they minimize its energetic costs. Its long, muscular neck further enables it to carry heavy prey away from other hyaenas and lions (Panthera leo), or to bring food to their cubs at the communal den.
Spotted hyaenas utilize almost every part of their prey except for horns and rumen, and scavenge often.
In the Serengeti and Ngongoro crater, Tanzania, the spotted hyaena was observed eating a wide variety of items including wildebeest, zebra, Thomson’s gazelle (Eudorcas thomsonii), Grant’s gazelle (Nanger granti), topi (Damaliscus lunatus), hartebeest (Alcelaphus buselaphus), waterbuck (Kobus ellipsiprymnus), common eland (Tragelaphus oryx), African buffalo (Syncerus caffer), impala (Aepyceros melampus), warthog, hare, springhare, ostrich eggs, bat-eared fox (Otocyon megalotis), golden jackal (Canis aureus), porcupine, puff adder (Bitis arietans), domestic animals, lion (Panthera leo), other hyaenas, termites, and afterbirth. Fecal analysis in these same two areas revealed that about 80% of the samples contained wildebeest, zebra, and various gazelle species. In a study in Senegal, hyaenas were found to prey on large herbivores such as buffalo, hartebeest, kob (Kobus kob), warthog, bushbuck (Tragelaphus scriptus). In addition, the spotted hyaena has been known to prey on the young of giraffe (Giraffa camelopardalis), hippopotamus (Hippopotamus amphibious), and rhinoceros.
The spotted hyaena is also a common predator on domestic livestock in Africa. Damage to domestic stock mainly involves cattle (Bos Taurus), sheep (Ovis aries), and goats (Capra aegagrus hircus) and varies widely in intensity.
In addition, the spotted hyaena has also been known to attack and kill humans, especially during human disease outbreaks.
In the Serengeti, many prey species of ungulates are migratory and are not found in spotted hyaena clan territory during some parts of the year. When this occurs, clans go on frequent, long-distance hunting and foraging trips to the nearest concentrations of prey. This system has been labeled a commuting system and allows the hyaena to live at much higher population densities than their clan territories would support. The average round trip for these expeditions is about 80 kilometers and a lactating female can make 40 to 50 trips per year for a total of 2,800 to 3,600 kilometers per year.
The commuting system of the spotted hyaena depends on the ability of hyaena clans to differentiate between commuting groups and groups that are actively searching for food. Aggression is rare between resident clan members and commuting individual hyaenas. Non-resident hyaenas typically defer to resident clan members at a kill, however this situation may also result in aggression.
Although long periods may elapse between drinking, spotted hyaenas are at least somewhat dependent on water. Spotted hyaena clans have been known to disperse after the only water source in their range dried up.
Mating in spotted hyaenas is highly polygynous and aseasonal. The age at sexual maturity is about three years, although some males may be sexually active at two.
Males perform a bowing display to females before mating. The male lowers his muzzle to the ground, advances quickly toward the female, bows again, and then paws the ground close behind the female. The dominance of females assures that males are timid and will retreat immediately if the female shows any aggression.
The female’s reproductive tract makes mating somewhat difficult. Male hyaenas approach and slide their haunches under the female to achieve intromission. Once intromission is acheived they move to a more typical mating posture, with the male’s underside resting on the female’s back. The female phallus is completely slack during mating.
The spotted hyaena’s gestation period is four months. Females usually bear twins although one to four young are possible. Females are capable of producing a litter every 11 to 21 months.
The females give birth through their penis-like clitoris. During birth, the clitoris ruptures to allow the young to pass through. The resulting wound takes several weeks to heal.
Although all females produce litters, alpha females have a younger age at first breeding, shorter interbirth intervals, and increased survival of offspring. These benefits are passed directly to female offspring. The mechanism responsible for the increased fitness of high ranking females is probably the increased access to food that alpha females receive. In addition, high ranking female hyaenas seem to preferentially give birth to sons.
Newborn spotted hyaenas weigh from 1 to 1.6 kilograms and are quite precocious, being born with their eyes open. Newborns are almost entirely black. If siblings are the same sex, they begin fighting violently soon after birth, which usually results in the death of one of the two. Since single young receive more food and mature faster, this behavior is probably adaptive.
The spotted hyaena has the highest parental investment of any carnivore for several reasons, however males have not been reported to have a role in parental care.
The major source of food for a young spotted hyaena is milk from the mother. Spotted hyaena milk has extremely high energy content as the mean protein content is 14.9%, and the mean fat content is 14.1%. This is only exceeded by some bears and sea otters (Enhydra lutris). Cubs are not weaned until they are between 12 and 18 months of age, which is extremely late. By the weaning age, juvenile hyaenas already have completely erupted adult teeth, which is also very rare.
Spotted hyaena females are also very protective of their young and do not tolerate other hyaenas around them at first. Females will intervene on behalf of their daughters in antagonistic encounters and form coalitions with them to secure the place of the daughters in the dominance hierarchy immediately below that of the mother. Infanticide has been witnessed several times in the wild both by hyaenas from neighboring clans and also by females from the same clan.
Two to six weeks after birth, the mother transports young from the burrow in which they were born, often an abandoned aardvark (Orycteropus afer), warthog, or bat-eared fox (Otocyon megalotis) burrow, to a communal den. Communal denning seems to be an important part of spotted hyaena social behavior, but no communal care of young takes place. One exception to this has been observed in the Kalahari during a particularly difficult period.
Spotted hyaenas are an extremely important component of the Serengeti ecosystem of Africa.
The spotted hyaena is one of the top predators in Africa, however, lions may kill them. In one study 13 of 24 hyaena carcasses found were killed by lions (Panthera leo). Spotted hyaenas and lions compete directly for food and often scavenge each other’s kills. This competition often leads to antagonistic encounters that may result in death.
Populations of spotted hyaenas are subject to persecution by humans in numerous ways including culling, trapping, and poisoning. Entire clans of spotted hyaenas may be killed by poisoning, and many individuals are killed when hit by vehicles, or by shooting and spearing. Such activities may sometimes occur within the boundaries of conservation areas, but are especially prevalent outside of protected areas. Through the early 1960’s, spotted hyaenas were shot on sight in numerous parks and game reserves in East Africa. Spotted hyaena populations in protected areas may also be decimated by authorities when they are considered a threat for other wildlife species such as lions (Panthera leo), cheetahs (Acinonyx jubatus), and rhinos. In some protected areas, spotted hyaenas may be legally killed by resident humans when they have preyed upon livestock. Government officials and managers allow local human residents within protected areas to kill spotted hyaenas when they are suspected or known to have preyed upon livestock. While it is fully protected in the Serengeti National Park in Tanzania, the spotted hyaena may be legally shot by sport hunters in the adjacent Maswa Game Reserve. The species is sport hunted in several places in Africa, though the hyaenas are not much in demand from trophy hunters because they are not viewed as attractive. Because they aren’t considered an attractive species, the numbers killed by licensed sport hunters are probably small. Spotted hyaenas are also killed for food, medicine, and witchcraft.
Mortality due to wire snares set to catch wild herbivores for meat is an important cause of adult hyaena mortality in the Serengeti, where snares kill around 400 adult spotted hyaenas each year and are responsible for more than half of all adult mortality. Apparently, only since the mid-1970s has game meat hunting rapidly expanded, as more people have moved within walking distance of the boundaries of protected areas such as in the north and west of the Serengeti.
Otherwise, this species is free of predators.
Because the spotted hyaena is a large, common carnivore in many parts of Africa, it is a valuable resource for safari companies and is considered an important part of the tourist industry. In at least two locations in Ethiopia, live, wild spotted hyaenas are utilized by locals for tourism. Tourists pay to feed the hyaenas by hand, and some believe that the hyaenas take away bad spirits and that feeding them will cure various ailments. In Nigeria, local people earn money by keeping spotted hyaenas and showing them to spectators on exhibition walks.
Hair and scraps of skin are often collected from dead animals and are used as talismans. In several areas in Tanzania, spotted hyaenas and their body parts are utilized for witchcraft.
The spotted hyaena is listed as Least Concern on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species as the species remains widespread in Africa, and the total world population well exceeds 10,000 mature individuals. There is a continuing decline in populations outside protected areas (and even within some protected areas) due to persecution and habitat loss, although this is not sufficient to warrant listing in a threatened category.
The spotted hyaena has been categorized as a Lower Risk species by the IUCN Hyaena Specialist Group.
A further threat is posed by the decline in densities of wildlife species consumed by spotted hyaenas due to habitat loss caused by increased human settlement, overgrazing by livestock, and game-meat hunting by humans.
Apparently, only since the mid-1970s has game meat hunting rapidly expanded, as more people have moved within walking distance of the boundaries of protected areas such as in the north and west of the Serengeti.
Legal classification of the spotted hyaena varies from vermin in parts of Ethiopia to fully-protected in conservation areas. Thus, while it is fully protected in the Serengeti National Park in Tanzania, the spotted hyaena may be legally shot by sport hunters in the adjacent Maswa Game Reserve. In some protected areas, spotted hyaenas may be legally killed by resident humans when they have preyed upon livestock.
The IUCN Hyaena Specialist Group has identified this species as conservation dependent. This means that there is currently a conservation program aimed at this species, but without this program the species would most likely be eligible for threatened status within 5 years.
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