Introduction to the Spotted Hyaena

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The spotted hyaena (Crocuta crocuta), the largest member of the family Hyaenidae, has a wide distribution in Africa south of the Sahara with the exception of tropical rain forests in West and Central Africa (Figure 1). In the northern and eastern part of its distribution spotted hyaenas overlap with another member of the Hyaenidae family, the striped hyaena (Hyaena hyaena), while in the south western part of Africa spotted and brown hyaena (Hyaena brunnea) can occur together (Dorst & Dandelot 1970). Both spotted hyena and the aardwolf (Proteles cristatus), the fourth member of the family Hyaenidae, are found in Hwange National Park, Zimbabwe.

Clan members know each other and are often related in matrilines (Mothers, daughters, sisters, aunts). Within a clan the society is organised in separate dominance hierarchies for each sex (Frank 1986a/b) with females being both dominant to and heavier than males (Frank 1986a, Hamilton et al. 1986). Males have their own dominance hierarchy but even the highest ranking male is lower in rank than the lowest female, so females are always dominant to males. Clan home range size and territorial behaviour varies depending on the density of spotted hyaenas, density of prey and the environment (Kruuk 1972, Bearder 1977, Mills 1985a, 1989, Estes 1991, Hofer & East 1993). In Hwange National Park the home range of the study clan is 300 sq. km.

After a gestation period of approximately 110 days spotted hyaenas give birth to 1-3 cubs in a birth den (Frank 1986a/b). Two to four weeks later the cubs are transferred to a communal den, where litters from different mothers and of cubs of different ages can be found (East et al. 1989). Spotted hyaena cubs are born with their eyes open and fully erupted canines and incisors (Kruuk 1972). When new-born their coat is a beautiful dark  chocolate brown, they then begin to get white faces at 2 months, their first spots appear towards the end of the third month and they are well-spotted by 4 months (Frank, pers. com.). In contrast to other social carnivores e.g. lions, female spotted hyaenas only suckle their

own cubs (see photo below).  They also have comparitively long lactation periods of 12 to 18 months (Krunk 1972, Estes 1991).

A mother lying at the front entrance to a tree den after her 1 month old cub has just suckled. Note how the  cub is chocolate brown and as yet has not developed its unique spot pattern.

A male spotted hyaena becomes sexually mature when he is about 2 years old and a female about 3 years. Young males leave their natal clan when about 2 -3 years old and become nomadic before settling in another clan, while in general females remain in their natal clan (Frank, 1986a, Holekamp et al. 1997). Spotted hyaena’s mating system is polygamous (one male will mate with more thn one female). Although the dominant male

does most of the mating, all the resident males court the females (Frank 1986b, Estes 1991). Female spotted hyaena have genitalia which look identical to that of the male and the sexes are therefore difficult to distinguish in the field. The female actually has a pseudopenis and pseudoscrotum but because of this similarity in genitalia it was falsely believed that hyaena were hermaphrodites and could change their sex. The pseudopenis is in fact an elongated clitoris and the pseudoscrotum consists of fatty tissue (Racey & Skinner 1979). The pseudopenis is erectile and is used in the special hyaena ‘Greeting Ceremony’ where hyaenas engage in much sniffing of the genital area in order to identify each other by scent. The shape of the very tip of the erect penis/pseudopenis is a method used by researchers to tell the sex of the hyaena (See photo below).

Two hyaenas greet ‘Blue Ear’ showing, from the shape of the erect penis tip, that she is a female.

It was previously believed that spotted hyaenas were only scavengers but research has shown that they are excellent hunters, preying on a variety of ungulates. Although they mostly tend to forage singly or in small groups they are opportunistic and excellent group hunters when catching large prey such as zebra or gemsbok (Eloff 1964, Kruuk 1972). Kruuk (1972) observed that in the Serengeti in 53% of cases, hyaenas made the kill and lions scavenged from it. However spotted hyaenas are

opportunistic feeders, easily switching from one food source to the next and the relation of hunting and scavenging varies with the environment (Eloft 1964, Bearder 1977, Mills 1978, Lindeque & Skinner 1982, Holekamp, Smale et al. 1997).

A cub and a sub-adult hyaena eat the remains of a zebra foal

General Facts on Spotted Hyaenas

1. Body Length 1.1 – 1.4 meters for fully grown Adult 2. Shoulder Height 79-89 cm 3. Weight 40-85 kgs – Females heavier than Males. Animals in Southern Africa in general heavier than those of East Africa. 4. Habitat: Savannas, grasslands, woodlands, forest edges, subdeserts and mountains to 4,000m 5. Breeding – no special breeding season, will breed all year round. 1-3 cubs born after gestation of 110 days. 6. Both sexes have similar genitalia. Copulation and birth occur through female’s phallus 7. Capable of killing a male wildebeest on its own, groups of 10 hyaenas can kill a zebra. 8. Live in groups called Clans. Clan numbers vary from approx. 30-80 in East Africa to 5-20 in Southern Africa. 9. Clans are Matriarchal (ruled by females). Both males and females have separate dominance hierarchies. The top ranked female is known as the Alpha Female. 10. Cubs born in a Birth Den then after 2 weeks moved to the clan Communal Den. 11. Cubs only suckled by their own mother. Weaned only after 12-18 months. Information taken from Collins Guide to African Wildlife (1996) and Julia's and Nolwenn's observations.