Brown hyenas prefer to den in arid to semi-arid grassland and savanna biomes at no higher than 1500 m in elevation, but are also found in desert regions that receive less than 100 mm of rain annually. By consuming fruit with a high water content as an alternative to fresh water sources they are able to survive in drier regions than spotted hyenas, their close relative. Den sites are typically located in sandy areas near large rocks or vegetative cover, which provides relief from the heat. Brown hyenas frequently scavenge for food along coastlines. (Attenborough, et al., 2002; Mills, 1982a; Owens and Owens, 1978; Owens and Owens, 1979; Skinner and Chimimba, 2005; Thunberg, 2010; Wiesel, 2008)
Brown hyenas are medium to large carnivores, averaging 40.7 kg in mass with a range of 34.2 to 72.6 kg. Body length averages 144 cm with a range of 130 to 160 cm. Owens and Owens (1996) found no significant evidence of sexual dimorphism between males and females. However, the average mass of males and females is sometimes listed separately at 47 kg and 42 kg respectively (Stuart and Stuart, 2001). Both sexes average 78.7 cm in height at the shoulder. (Mills, 1982a; Nowak, 2005; Owens and Owens, 1996; Skinner and Chimimba, 2005; Stuart and Stuart, 2001; Wiesel, 2008)
Hyaenidae, surpassed in size only by spotted hyenas. Like all members of the family, the forelegs of brown hyenas are significantly longer and more massively built than the hind legs, giving their profile a sloping appearance as if they were constantly walking uphill. The forefeet are also noticeably larger than the hind feet, and the chest, shoulders, neck and skull are heavily built. The teeth of are massive, even in comparison to other large carnivores. The upper carnassial tooth is particularly large and well developed as an adaptation for crushing bone. (Mills, 1982a; Nowak, 2005; Owens and Owens, 1996; Skinner and Chimimba, 2005; Stuart and Stuart, 2001; Wiesel, 2008)is the second largest member of the family
The most obvious way to distinguish Hair on the neck and back can reach 30.5 cm in length. This is in contrast to short hair on the face and ears, as well as the legs, which are horizontally striped. The erect ears are larger and more pointed than those of spotted hyenas and resemble those of striped hyenas. The tail is relatively short and bushy, with roughly the same coloration as the body. (Mills, 1982a; Nowak, 2005; Owens and Owens, 1996; Skinner and Chimimba, 2005; Stuart and Stuart, 2001; Wiesel, 2008)from other members of its family is by the long, shaggy hair, which is usually dark brown to black on the body and tan on the shoulders and neck.
Brown hyenas typically mate during the African dry season from May to August, following a brief courtship that may last from 3 to 6 nights. They generally exhibit one of two complex mating systems. The first is a clan-based polygynous system, which only occurs when the clan’s alpha male is a non-related individual from another clan. Related males and females generally do not show sexual interest in one another, however males born into a clan have been observed to rise to the status of alpha male and reproduce with clan females on rare occasions. In this first scenario, the alpha male mates with all clan females that are sexually receptive at any given time. He aggressively defends the clan from male intruders using piloerection and biting when necessary. If a nomadic female ventures into the clan’s territory, he may also mate with her. The second mating system consists of the sexually receptive clan females mating primarily with one or more nomadic males that venture into the clan’s territory. This system is either polygynous or promiscuous, with females occasionally mating with as many as four different males. In this scenario, both male and female clan members tolerate the presence of nomadic males. Nomadic individuals likely locate clans by sense of smell, using territorial scent markings and latrine sights made by the clan. (Mills, 1982b; Mills, 1982a; Owens and Owens, 1996)
Brown hyena clans exhibit cooperative breeding. Mothers suckle the cubs of other females, and all clan members take part in bringing food back to the den for cubs that are too young to hunt. (Mills, 1982b; Mills, 1982a; Owens and Owens, 1996)
Female brown hyenas may have more than one estrus cycle per year (i.e., polyestrus). Cubs are born with their eyes closed after an average gestation of 97 days. Newborns weigh an average of 693.2 g and are similar in coloration to their parents, but with shorter fur. Litters range in size from 1 to 5 individuals per female (2.3 on average) with alpha females generally having a higher lifetime reproductive output than subordinates. Cubs are almost entirely dependent on their mother’s milk for the first 3 months of their lives, but they may also occasionally suckle from other clan females. Weaning takes place when the cubs are 3 to 12 months old. Once weaning begins, their diet is gradually supplemented by red meat brought back to the den by other clan members. Cubs spend most of their time within or very close to the den until they reach 15 months of age. From 15 to 30 months of age, individuals are referred to as subadults and are capable of foraging independently. Females become sexually mature by 24 months, and males become sexually mature by 40 months. Females may wait anywhere from 12 to 41 months between successive litters. (Mills, 1982b; Mills, 1982a; Owens and Owens, 1996; Skinner and Chimimba, 2005)
Brown hyena mothers usually give birth to their cubs in private satellite dens and then introduce the cubs to the clan’s communal den before they are 4 months old. Mothers nurse their cubs until they are at least 10 months old (in some cases up to 14 months), but it is common for other lactating females to help by allowing non-offspring to nurse as well. Young cubs sometimes indicate a desire to suckle by pushing on the mother’s mammary glands with their front paws, a behavior know as “milk treading”. A typical nursing bout lasts for 25 to 30 minutes, but is sometimes extended if begging persists. Cubs less than 4 months old are fed 2 to 3 times per night, while older, weaning cubs often suckle only once every few nights. During weaning and prior to independence, mothers remain somewhat partial to their own offspring, but all clan members (both male and female) bring back scavenged food for the cubs. Adults carry food back to the den in their mouths and do not regurgitate as in some mammals. Females spend short periods of time sleeping and socializing with cubs near the den between nightly hunts, but both males and females typically sleep further away from the den during the day. Although fathers bring food back to the den, they do so less frequently than females and no more often than other clan males. Aside from bringing back food, paternal care by the alpha male also includes protecting cubs from predators and intruders from other clans. Mothers and other adult females also share in this task. Most cubs become independent by 15 months of age, but may still rely on communal food at the den until they reach 30 months of age. (Owens and Owens, 1979; Owens and Owens, 1996)
In the southern Kalahari Dessert, 86% of brown hyena cubs survived to at least 15 months of age. Hunting by farmers is a common cause of death for young adults and subadults who wander out of their territory. Mature adults typically have a low mortality rate, and their greatest threat is the presence of larger carnivores such as African lions. For individuals that reach old age (around 10 years), tooth wear is the limiting factor for survival, and most die as a result of inadequate nutrition. (Mills, 1982a; Skinner and Chimimba, 2005)
Brown hyenas live either nomadically or as members of a clan. Approximately one third of all males are nomads that have left their birth clans and are searching for another clan to join as the alpha male. Females are occasionally nomadic, but only when they do not have cubs to care for. Brown hyena clans are small, normally made up of 5 to 15 individuals. Clans typically consist of genetically related males and females, but alpha males are usually migrants from another clan. The social structure of the clan consists of both male and female linear dominance hierarchies that can be independent of age. The alpha male and alpha female share equal positions in the clan hierarchy, and unlike spotted hyenas, brown hyena females are not consistently dominant over males. Dominance is established through ritualized bites to the legs and neck, as well as muzzle wrestling. Dominant individuals exhibit behaviors such as snapping their teeth, chasing, and raking their hind feet in front of subordinates. Brown hyenas use piloerection on their back and neck (also known as the hackle) as an aggressive or defensive gesture. When the display is aggressive, the mouth is closed, ears are alert and tail is up. In a defensive posture, the mouth is wide open and the ears lay flat against the back of the head. When individuals encounter one another, subordinate individuals greet by crouching low to the ground in a stereotypical posture and lifting its tail to present the anal scent gland. They flatten their ears outward at a 90-degree angle, and the lips are pulled up into what is generally described as a grin. This behavior is sometimes accompanied by squealing by the subordinate. Cubs practice these behaviors with one another from an early age. (Hulsman, et al., 2010; Mills, 1982b; Mills, 1982a; Mills, 1982c; Nowak, 2005; Owens and Owens, 1978; Owens and Owens, 1979; Owens and Owens, 1996; Skinner and Chimimba, 2005; Wiesel, 2008)
Brown hyenas utilize latrine sites for defecation throughout their territory, especially near the den and other strategic locations such as kill sites and territorial boundaries. These sites are used mostly for communication between clan members, along with scent markings. Cubs always leave the den to defecate. A bone collection site often accompanies brown hyena dens, and serves as a disposal point for the remains of food items brought back to the cubs. This site is usually located within a chamber of the den, and provides useful information regarding the clan’s diet. (Hulsman, et al., 2010; Mills, 1982b; Mills, 1982a; Mills, 1982c; Nowak, 2005; Owens and Owens, 1978; Owens and Owens, 1979; Owens and Owens, 1996; Skinner and Chimimba, 2005; Wiesel, 2008)
Nomadic individuals are not territorial and therefore do not defend specific home ranges. In contrast, clans defend home ranges averaging 300 square kilometers, with some growing to as large as 480 square kilometers. Home range size changes periodically as a result of environmental conditions, growing larger when food and climate conditions are favorable. This territory includes the communal den site, smaller satellite dens and most of the hunting grounds used by the clan. The boundaries of a clan's home range are regulated using scent markings. Within the clan's territory, some individuals (many times a new mother with cubs) spend short periods of time in smaller sub-territories that average around 40 square kilometers in size. (Mills, 1982a; Nowak, 2005; Owens and Owens, 1978)
In addition to scent markings, brown hyenas communicate using two visual displays via piloerection of the long fur on their hackles. In an aggressive display, the tail is laid against the back, the ears are alert and the mouth is closed. Defensive displays are characterized by an open mouth and flattened ears. Cubs communicate their desire to suckle by pushing on the female’s mammary glands with alternating front paws. Cubs also groom one another and the adults as a way of bonding. Vocal communication is also an important part of social behavior in brown hyenas. Whines and squeals are used as a warning for approaching predators and as a sign of submission to dominant individuals. A relatively quiet call is used to order cubs into the den. Deep growls sometimes accompany a meeting between rivals from separate clans, and shrieks are used to announce the presence of other predators at a newly discovered carcass. (Attenborough, et al., 2002; Gorman and Mills, 1984; Mills, 1982a; Skinner and Chimimba, 2005; Wiesel, 2008)
African lions, and leopards. Frequently consumed food items in this area include springbok, springhare, gemsbok and Burchell's zebra. Populations living closer to the Skeleton Coast in western Namibia primarily feed on black-backed jackals and South African fur seal pups that have wandered from their parents or drowned. In both regions, birds such as the crowned plovers and helmeted guineafowl also make up a significant portion of their diet. In addition to meat, brown hyenas consume a high volume of tsama melon (Citrullus vulgaris), hookeri melon (Cucumis hookeri) and gemsbok melon (Citrullus naudinianus) as supplements for fresh water during the dry season. This feature of their diet allows brown hyenas to live in more arid regions than their close relative, the spotted hyena. Excess food that cannot be consumed in a single feeding is sometimes buried under shrubs or bushes and recovered the following day. Brown hyenas are also known to be coprophagic, which is thought to reduce water loss in arid land species. (Attenborough, et al., 2002; Maude, 2005; Nowak, 2005; Owens and Owens, 1978; Skinner and van Aarde, 1991; Wiesel, 2008)is a generalist and a highly opportunistic feeder. Individuals primarily scavenge for carrion, using their acute sense of smell to locate carcasses and their specialized teeth to crush bone. Brown hyenas do not typically hunt live prey, but when an opportunity arises, they do not hesitate to pursue small birds or mammals over short distances. Diets vary from inland Botswana populations to those in the Namib Desert and along the Skeleton Coast. The diet of inland populations is largely composed of carcass remains from the kills of other large carnivores, such as
African lions are the only major predator of adult brown hyenas. Spotted hyenas can also kill adult brown hyenas, but encounters between the two species rarely occurs due to their differing habitat preferences. Brown hyena cubs are susceptible to predation from lions, black-backed jackals and occasionally African wild dogs. Group living likely reduces predation of brown hyena cubs by these animals. When a predator approaches the den, the smallest cubs, usually those under 4 months in age, retreat underground while older cubs stand just outside the entrance with their hair erected. (Mills, 1982c; Owens and Owens, 1978; Owens and Owens, 1979)
Adult brown hyenas are most at danger when approaching a lion kill, and they sometimes delay feeding for up to 30 minutes after the lions have left to ensure their safety. They also use raised hackles and a loud, high-pitched cry to alert others of approaching lions. (Owens and Owens, 1978; Owens and Owens, 1979)
Brown hyenas help regulate populations of black-backed jackals and South African fur seals through predation. They also alter predation frequencies of cheetahs and leopards by stalking them during hunts and then driving them off of their kills. Brown hyenas also disperse the seeds of tsama melons (Citrullus vulgaris), hookeri melons (Cucumis hookeri) and gemsbok melons (Citrullus naudinianus) at defecation sites. (Owens and Owens, 1978)
Some pastoralists in southern Africa feel that brown hyenas are beneficial as a target for ecotourism, which brings money and jobs into the region. Brown hyenas also benefit humans by controlling parasite populations that rely on animal carcasses to feed and reproduce. By reducing the number of carcasses, brown hyenas help decrease chances of parasitic infestation to humans, livestock and domestic pets. (Maude, 2005)
African lions, black-backed jackals and spotted hyenas. It has been estimated that over the course of a year at a single cattle post, brown hyenas are responsible for $94 worth of damage to livestock, out of an annual total of $744 worth of damage caused by all predators. On average, it is estimated that brown hyenas kill 1.8 domestic animals per ranch annually. Many farmers set indiscriminate traps and shoot brown hyenas in an attempt to keep their livestock and crops safe. (Maude, 2005)is viewed as a livestock killer and crop pest by melon farmers. In many cases this is a misconception, with the true killers being
Brown hyenas are considered near threatened with a decreasing trend by the IUCN Red List of Threatened Species, and the U.S. Fish and Wildlife Service has listed them as endangered since 1970. It is difficult to make accurate population estimates of brown hyenas due to their nocturnal lifestyle and low population density. Low population numbers are probably due to sparse resources in the Kalahari and Namib Deserts, as well as persecution from livestock farmers in the area. The establishment of national parks and game reserves in Namibia and Botswana offer the best hope for preserving brown hyena populations. (Mills, 1982a; Nowak, 2005; Skinner and van Aarde, 1991)
Mike Schmidtke (author), University of Michigan-Ann Arbor, Phil Myers (editor), University of Michigan-Ann Arbor, John Berini (editor), Animal Diversity Web Staff.
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
uses sound to communicate
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
helps break down and decompose dead plants and/or animals
an animal that mainly eats meat
flesh of dead animals.
uses smells or other chemicals to communicate
helpers provide assistance in raising young that are not their