Species richness and abundance of large mammals in Zaraninge forest, Coast region, Tanzania

Abstract

A study on the large mammals of Zaraninge Forest was conducted using the line transect method between 1995 and 2001. They comprised 16 species from 7 families, including Bovidae (5), Canidae (1), Cercopithecidae (4), Felidae (1), Galagonidae (2), Orycteropodidae (1) and Suidae (2). Only nine species of primates and antelopes were encountered frequently enough for densities to be estimated. A total of 404 sightings from 40 counts were recorded, the majority being for blue monkey (34.9%) and Angolan colobus (26.0%). For galagos, 210 sightings from 58 counts were recorded, the majority being for Rondo galago (62.2%). Absolute density (individuals km-2) (±SE) for blue monkey (12528.8) was highest, followed by the Angolan colobus (74.03.9) and yellow baboon (33.68.1). Antelopes had much lower densities with that of suni (23.48.7) being the highest, followed by Harvey's red duiker (13.6±9.5), blue duiker (9.5±6.4) and bushbuck (2.3±0.5). Densities for the Rondo galago and Zanzibar galago were 23.4±9.1 and 12.9±10.5, respectively. Only one bushbuck pellet pile was encountered while for the two duikers and suni a total of 106 fresh pellet piles were counted. Relative pellet pile density (piles km-2) for suni was 280.1±73.7, while for red duiker and blue duiker densities were 170.9±50.6 and 119.9±52.9, respectively. Endemic large mammals were not observed in the forest though six were forest specialists, one near endemic, six threatened and seven in the CITES list.