Galagoides zanzibaricus

7.

Tanzania Coast Dwarf Galago

Galagoides zanzibaricus

French: Galago de Zanzibar / German: Sansibar-Zwerggalago / Spanish: Gélago pequeno de Tanzania

Other common names: Matundu Dwarf Galago, Zanzibar Bushbaby, Zanzibar Galago; Udzungwa Dwarf Galago (udzungwensis), Zanzibar Dwarf Galago (zanzibaricus)

Taxonomy. Galago zanzibaricus Matschie, 1893,

Tanzania, Zanzibar, Yambiani.

This is a polytypic species, but its taxonomy remains unresolved. It is probably a “waste basket taxon” for several species. It was regarded as a subspecies of G. senegalensis by E. Schwartz in 1931, and the specific name was revived by J. Kingdon in 1971. T. R. Olson moved it from the genus Galago to Galagoides in 1979, and three species were subsequently split off:

G. granti, G. nyasae (not recognized here, see G. granti taxonomy section), and G. cocos. Two subspecies are recognized.

Subspecies and Distribution.

G. z. zanzibaricusMatschie, 1893 — NETanzania (ZanzibarandMafiaIs); absentfromPembaI.

G. z. udzungwensis Honess in Kingdon, 1997 — NE Tanzania (Udzungwa at Kihansi, Uluguru, and East Usambara Mts S to the Rufiji River) and Mafia I.

Descriptive notes. Head-body 12-18 cm, tail 17-24 cm; weight 100-200 g. There is no apparent sexual dimorphism or dichromatism in the Tanzania Coast Dwarf Galago. The “Zanzibar Dwarf Galago ” (G. z. zanzibaricus) is bufty-grayish dorsally, with a creamy-gray underside. Its tail is only slightly darkened toward the tip, and it has yellowish cheeks and throat. It has thick, black eye-rings, continuous with the black on the sides of the muzzle, and a thick white stripe that runs from the forehead to the rhinarium. The skin of the ears is not deeply pigmented. The “Udzungwa Dwarf Galago ” (G. z. udzungwensis) is smaller. Its pelage is grayish-brown above grading to yellowishbuff ventrally, with an orangey-buff throat. It has a broad white mid-facialstripe, and cheeks are yellowish-buff. There are no distinct eye-rings. Thetail is gray-brown, and it is evenly and sparsely furred.

Habitat. Secondary lowland tropical, coastal dry evergreen, groundwater, and submontane forests; brushland; coconut groves; and coral-rag thicket. Tanzania Coast Dwarf Galagos are found from sea level to 1070 m, but the highest point on Zanzibaritself is 120 m. The little we know aboutthis species suggests that they prefer to spend their time in the trees, rarely coming to the ground, preferring mid to high height classes, above 5 m.

Food and Feeding. Like other small galagos, the Tanzania Coast Dwarf Galago seems to be a faunivore-frugivore with a preference for animal prey (including insects, such as beetles and ants, and birds), supplemented with fruit (e.g. Trichilia emetica, Meliaceae, and Vitex, Lamiaceae). It does not eat gum.

Breeding. There are two birth seasons per year (February-March and August-October). A single young is born after gestation of c.120 days, although sometimes they have twins. Infants are carried in the mother’s mouth. Sexual maturity occurs at about twelve months. One individual of the nominate subspecies lived for 16 years and six months in the San Antonio Zoo, USA.

Activity patterns. The Tanzania Coast Dwarf Galago is nocturnal and arboreal. It uses the fine-branch niche, with quadrupedal walking and running when moving along tops of horizontal branches and leaping between more vertical stems and trees.

Movements, Home range and Social organization. The Tanzania Coast Dwarf Galago is mainly solitary, although groups of 2-6 individuals may sleep together. Nests are usually in tree holes or tangles of dense vegetation 4-8 m from the ground. Leaf nests may comprise green leaves or coconut palm, and individuals can make up to ten trips to assemble a nest. Little is known aboutits behavior at night, but most observations (92%) have been of solitary individuals. The main vocal advertisementis a “single unit rolling call.” These galagos commonly produce this call at dusk or before dawn for reassembly of sleeping groups, and it seemsto serve as a gathering call. Other calls include a buzz, rapid whistle, descending shriek, screech, screech-grunt, and yap.

Status and Conservation. CITES Appendix II. Classified as Least Concern on The [UCN Red List. The Tanzania Coast Dwarf Galago is relatively widespread and common, but the subspecies zanzibaricusis listed as Endangered, being entirely confined to the southern and eastern parts of Zanzibar Island and on nearby Mafia Island, where, although common, its habitat is fragmented and continues to be degraded and transformed. The Tanzania Coast Dwarf Galago occurs in Jozani Chwaka Bay and Udzungwa national parks and Kiamboza, Kihansi, and Matundu forest reserves in Tanzania.

Bibliography. Anderson (2000), Bearder (1987), Bearder, Ambrose et al. (2003), Bearder, Honess & Ambrose (1995), de Boer (1973), Burgess et al. (2000), Butynski, Ehardt & Struhsaker (1998), Butynski, de Jong et al. (2006), Harcourt (1986a), Harcourt & Bearder (1989), Harcourt & Nash (1986a, 1986b), Honess (1996), Honess & Bearder (1996), Kingdon (1971, 1997), Lumsden & Masters (2001), Masters et al. (1993), Nash (1983), Olson (1979), Perkin (2000, 2004, 2007), Ying & Butler (1971).