Galago zanzibaricus
Zanzibar bushbaby
(Also: Zanzibar galago)

Galago zanzibaricus, commonly known as Zanzibar bushbabies, can be found in the East African coastal forests from southern Somalia to Mozambique. As the name suggests, they are also native to the island of Zanzibar. However, this species cannot be found on Pemba and Mafia, two nearby islands. Some researchers maintain that the north boundary of this species is the Tana River in Kenya. They are also found up to a few hundred kilometers inland in the Udzungwa Mountains. (Butynski, 2004)

Galago zanzibaricus lives in tropical, lowland coastal forests. They are also found at higher elevations further inland. They have been found at elevations greater than 1,000 m in the montane forests of Tanzania and Malawi. Population densities are highest near rivers. There is little inter-group exchange among G. zanzibaricus as populations are extremely fragmented. ("Ngaramia Riverine Forest Conservation Project", 2003; Butynski, 2004)

Zanzibar bushbabies are generally brown in color. The underside is a lighter shade of brown. The fur is heavy and soft. They have stunningly large red eyes which help them to see at night. The ears are extremely large and the hind limbs are strong and significantly longer than the fore limbs. There is little dimorphism between males and females. The average weight of an adult is 146.8 g. The average weight of an infant at birth is 14.1 g. The body length from head to tail ranges from 14 to 15 cm and the tail length varies from 12 to 15 cm. ("An Age entry for Galagoides zanzibaricus", 2005; Butynski, 2004)

Some reports estimate maximum longevity in the wild is 16.5 years. The longest lifespan of a captive G. zanzibaricus is 12.2 years. ("An Age entry for Galagoides zanzibaricus", 2005)

Zanzibar bushbabies are nocturnal, resting during the day and foraging at night. They are arboreal and spectacular climbers. These animals are agile and use their tail for balance. They have the ability to safely run and leap from limb to limb. Both males and females are territorial and maintain non-overlapping territories (occasionally minor overlapping is seen). Male G. zanzibaricus are rarely found in the same territory other males. Occasionally, however, two females occupy the same territory. They usually sleep together but go their different ways during active periods. Galago zanzibaricus typically travel between 1,500 and 2,000 meters per night. Young females remain in their natal ranges after males disperse. Male dispersal prevents incest from occuring. (Butynski, 2004; Harcourt and Nash, 1986; Nunn, 1999)

Home Range

In one study, the average home range size was found to be about 2.2 ha. Range size varies from 1.6 to 2.8 ha. (Harcourt and Nash, 1986; Nunn and Barton, 1999)

The large eyes of Zanzibar bushbabies provide excellent vision at night and the large ears provide an acute sense of hearing. Both attributes are important for navigation in the dark. These animals have loud, distinctive calls about which little is known. They may be a sort of "advertising" call, but they also seem to be used as a warning to others when potential predators are nearby. Like most mammals, chemical cues are probably also important in communication. (Butynski, 2004; Nash, 1983)

The diet of Galago zanzibaricus is mostly composed of fruits, insects, and tree gums. Seasonal variation in resource availability plays an important roll in determining what the animals eat. For example, when it rains a lot there may be an abundance of insects, but when no rain falls Zanzibar bushbabies must look to other resources. Occasionally a Zanzibar Bushbaby will prey on other small animals. (Butynski, 2004; Nash, 1983)

Their arboreal lifestyle protects Zanzibar bushbabies from many potential predators. They produce warning calls in the presence of genets and puff adders, suggesting that they may be predators of G. zanzibaricus. (Butynski, 2004; Nash, 1983)

Zanzibar bushbabies may disperse the seeds of the fruits they consume.

There are no negative impacts of Galago zanzibaricus on humans.

Zanzibar bushbabies are important members of the ecosystems in which they live, they are also a potential draw for ecotourism efforts.

Galago zanzibaricus is classified as vulnerable on the IUCN Red List. Although the species as a whole is widespread and fairly common, its fragmented range results in potential extinction of individual populations. The main threat to this creature is habitat loss due to urbanization and deforestization. Also, the indigenous forests used by G. zanzibaricus are being replaced with exotic conifers, which do not provide appropriate habitat for this species. Zanzibar bushbabies are protected by law in Kenya as well as in certain conservatories such as the Tanzania Forest Conservation Group. Despite these efforts, only about 12% of their total range is protected. ("Ngaramia Riverine Forest Conservation Project", 2003; Butynski, 2004)

The phylogenetics of G. zanzibaricus has a complicated history. In recent years this creature's place within primate phylogeny has been anything but stable. Three major techniques have been utilized: morphological analyses, molecular analyses, and analysis of vocalization data. Analyses based on these data support different hypotheses of relationship and outgroup rooting seems to be a problem. This species was previously known as Galago zanzibaricus, it was then placed in the genus Galagoides as Galagoides zanzibaricus, and was recently returned to the genus Galago. (Butynski, 2004; Masters and Brothers, 2002)

Galago zanzibaricus has been divided into two subspecies Galago zanzibaricus zanzibaricus and Galago zanzibaricus cocos. There are few morphological differences between the two, and experts cannot tell them apart visually. However, they have highly distinctive vocalizations and Galagoides zanzibaricus cocos was recently elevated to species status, Galagoides cocos. (Butynski, 2004; Masters and Brothers, 2002)