Dendrohyrax arboreus is found in Africa along the southeastern coast. Its range extends southward from Kenya and Uganda to South Africa, and from eastern portions of the Democratic Republic of the Congo and Zambia in the west to the eastern coast of the continent.

Biogeographic Regions: ethiopian (Native )

D. arboreus has a somewhat marmot-like or guinea pig-like appearance. Long, soft, grey-brown fur covers the body, while the underside is paler. Hairs are lighter near their tips. The ears have a fringe of white hair. A dorsal gland is conspicuous in the middle of the back as it is ringed by creamy white hairs (total length 23-30 mm). D. arboreus lacks an obvious external tail.

These animals weigh about 2.27 kg on average, and have an average length of 520 mm. The BMR for this species is reported to be somewhat low for its size.

Four sub-species are recognized: D. arboreus stuhlmanni, D. arboreus crawshayi, D. arboreus ruwenzorii, and D. arboreus aldofi-friederici. Ranges overlap, although some habitat differentiation has been reported where the sub-species co-occur.

Average mass: 2.27 kg.

Average length: 520 mm.

Sexual Dimorphism: male larger

Average mass: 3000 g.

• Terrestrial

• Terrestrial

D. arboreus lives in forested areas that contain a mix of older and younger trees. The variety of forested environments it inhabits ranges from alpine, montane, highland, lowland, and riverine forests. It may be found at elevations up to 4500 m.

Range elevation: o to 4500 m.

Habitat Regions: temperate ; tropical ; terrestrial

Terrestrial Biomes: savanna or grassland ; forest ; rainforest ; scrub forest ; mountains

Other Habitat Features: riparian

D. arboreus is generally folivorous. However, other plant parts constitute a large proportion of its diet. It is a selective browser, eating a combination of foods to maintain a delicate energy balance, not necessarily in proportion to the item’s abundance. Nearly 150 individual plant species were identified from fecal remains of D. arboreus in South Africa. The most commonly eaten species may constitute a low of 38% of the total diet, and two dozen species may only constitute 75% of all material eaten.

Different parts of plants are consumed by D. arboreus. These include leaves, petioles (discarding the leaf), twigs, shoots, fleshy fruit, and hard seeds. Individual species are too many to list, but Hagenia abyssinica, Hypericum revolutum, Ficus spp., and Podocarpus falcatus are common.

Plant Foods: leaves; wood, bark, or stems; seeds, grains, and nuts; fruit

Primary Diet: herbivore (Folivore )

Southern tree hyraxes disperse the seeds of fruits they eat. Their waste products contain high amounts of calcium carbonate, which eventually form "outcroppings" and may play a role in localized nutrient cycling. As hyraxes generally are the major prey of Verreaux eagles, D. arboreus may have a significant impact on this species. Finally, as cavity-dwellers, they may provide structural components of forests.

Ecosystem Impact: disperses seeds; creates habitat

Verreaux eagles subsist almost entirely on hyraxes. Additionally, Martial and Tawny eagles, leopards, lions, jackals, spotted hyenas, and snakes prey upon hyraxes. In Rwanda, the most common predators are feral dogs. It has been speculated that the exceptionally limited amount of time D. arboreus spends on the ground at night may be a predator avoidance strategy to avoid the dogs. Humans are also known to eat D. arboreus.

Known Predators:

• snakes (Serpentes)
• feral dogs (Canis lupus familiaris)
• humans (Homo sapiens)
• lions (Panthera leo)
• leopards (Panthera pardus)
• jackals (Canis)
• Verreaux's eagles (Aquila verreauxii)
• martial eagles (Polemaetus bellicosus)
• tawny eagles (Aquila rapax)

D. arboreus has a prominent scent-gland, which may be used in marking territory or communicating. The large "latrines" under their den trees clearly demarcate use of a home range.

Throughout their range, southern tree hyraxes are particularly well known for their nighttime screaming. During the dry season, males will call in the early morning hours (between 2 an 4 AM). There appears to be a social communicative function to these calls. "Each animal builds up to a strained crescendo of screams and a calling animal appears to initiate responses from its neighbours so that on a suitable night there may be concert periods of croaking screams ringing out through the forest." (Kingdon 1971, p.328)

A clear interpretation of this behavior has not been made: there was no correlation between frequency, intensity, duration, initiation time of calls, or environmental variables. Breeding activities were not investigated in tandem with calling behavior. One interpretation is that calling follows intense feeding periods but is linked to territoriality and sexual function.

Some tactile communication undoubtedly occurs between mothers and their young, as well as between mates. Although these animals can see, it is not known whether they use any visual signals in their communication.

Communication Channels: tactile ; acoustic ; chemical

Other Communication Modes: choruses ; scent marks

Perception Channels: visual ; acoustic

Hoeck reports the longevity for the genus Dendrohyrax as "10 years plus." A captive female, pregnant when brought into captivity, lived at least four additional years, though her lifespan after the study ended is not reported.

Average lifespan

Status: wild: 10 years.

Average lifespan

Status: wild: 10.0 years.

Average lifespan

Status: captivity: 12.3 years.

Milner and Harris (1999b) reported that they were unable to determine the mating system of D. arboreus, but speculate that it may be facultative monogamy/polygyny, similar to some folivorous marsupial or primate species. Nonetheless, "it was quite apparent that their social system was very different from that of the colonial rock and bush hyrax." (Milner and Harris 1999b, p.292)

During an activity study of radio-collared animals, two male-female pairs had similar activity patterns and ranges, suggesting to the authors that either seasonal or longer-lasting bonds were indicated.

Mating System: monogamous ; polygynous

Breeding may occur throughout the year for D. arboreus, as evidenced by juveniles of several sizes simultaneously present in one population in Rwanda. A captive D. arboreus male-female pair produced offspring in June from a pregnancy that began before captivity and in December each year thereafter. One to two young (more often two) were born each time, and suckling began within a few hours, although the time to weaning steadily decreased from 7 months for the first litter to 3 months for the last birth.

Breeding interval: Captive D. arboreus breeds once yearly.

Breeding season: Breeding seasons have not been observed.

Range number of offspring: 1 to 2.

Average number of offspring: 2.

Average gestation period: 7 months.

Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous

Average birth mass: 380 g.

Average gestation period: 229 days.

Average number of offspring: 2.

Average age at sexual or reproductive maturity (male)

Sex: male: 365 days.

Average age at sexual or reproductive maturity (female)

Sex: female: 365 days.

There is very limited information on parental investment in D. arboreus. Mothers may nurse for 3 to 7 months, and it is presumed that the young would den with their mother during this time. Individuals with deciduous teeth remaining, presumably juveniles, were observed to be solitary during a radio-collar study. However, one group, consisting of an adult, two sub-adults, and a juvenile were repeatedly found in each other's company also. This may indicate some parental investment once the young leave the den.

One account reported that offspring may eat solid food beginning their second or third day.

Parental Investment: no parental involvement; precocial ; female parental care ; pre-fertilization (Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence; post-independence association with parents

The IUCN lists D. arboreus in South Africa as VU B1+2 status as of 1996, meaning it is vulnerable ("a high risk of extinction in the wild in the medium-term future"), due habitat fragmentation and continued population decline. In fact, there have been recent studies documenting the habitat needs of D. arboreus in an effort to curb its decline.

US Federal List: no special status

CITES: no special status

IUCN Red List of Threatened Species: least concern

It is possible that D. arboreus may be a minor nuisance to agriculturalists. There is also some chance that this species is part of the life cycle of parasites capable of infecting humans. A species of Dendrohyrax located in Kenya and Ethiopia harbors the leishmaniasis-causing parasites.

Negative Impacts: injures humans (carries human disease); crop pest

D. arboreus has economic importance to humans in a number of different ways. The crystallized excrement of this species has been used by both Europeans and South African tribes as a medicinal to treat epilepsy, hysteria, St. Vitus's dance, and general injuries. It has also been used as a vitamin supplement. Humans hunt Dendrohyrax spp. for food, and it is said that their large liver is a delicacy. Finally, the fur of this species may have some value, as the pelts of other members of the genus, such as D. arboreus, are used near Mt. Kilimanjaro. The fur of tree hyraxes is generally quite soft.

Positive Impacts: food ; body parts are source of valuable material; source of medicine or drug ; produces fertilizer