The brown hyaena is a polyoestrous, non-seasonal breeder with anoestrous occurring during lactation. The gestation period is approximately 97 days and mean litter size is 2.3 (range: 1-5 cubs) (Mills 1982b). Both nomadic and immigrant males may mate and all adult females in a clan may reproduce, although the matriarch apparently produces more cubs than other female clan members.
Brown hyaena females give birth and raise their young in dens; these are often created by aardvarks, but are occasionally dug by the female hyaenas. The den is usually a single hole in the ground with a narrow entrance of about 30 cm height and 50 cm width (Mills 1982b), although in some areas caves are used (Skinner 1976, Goss 1986). At most dens, a single litter of cubs is raised, but two or even more females may share a den in territories where more than one female breeds (Owens and Owens 1979a; Mills 1990). The breeding females are usually a mother and her adult daughters; the adult females in a clan may even suckle each other’s cubs, although they give priority to their own cubs.
The denning period lasts 15 months, during which time the cubs use several different dens. In the southern Kalahari, each den is occupied for an average of 3.6 months (Mills 1990). At birth, brown hyaenas have the same body coloration as adults. For the first three months of their lives, the cubs are nursed by their mother, typically at sunset and sunrise, after which the milk diet is supplemented to an increasing degree by food that is carried to the den by all clan members. Consequently, brown hyaena dens often become littered with bones and other food remains (Mills and Mills 1982a). The cubs are weaned at 12-14 months of age, but from about ten months of age, they also begin to forage for themselves. Brown hyaenas reach full size by approximately 30 months of age (Mills 1982).