The Angola black-and-white colobus (Colobus angolensis palliatus) in Kenya: historical range contraction and current conservation status

Abstract

The Angola black-and-white colobus (Colobus angolensis palliatus) is a flagship species for Kenya's coastal forests, a global biodiversity hotspot and a region for "priority" conservation investment. This study provides the first evaluation of colobus distribution, status, and current threats within its Kenyan range: the southern coastal District of Kwale. Line transect and sweep count surveys were carried out between July and November of 2001, covering 25,514 ha of coastal forest within 124 forest fragments. A total of 55 colobus populations were located, with total Kenyan C. a. palliatus population estimates ranging between 3,100 and 5,000 individuals (560-900 groups). The Shimba Hills National Reserve protects both the largest forest and largest colobus population in the District. A total of 3,000 ha of coastal forest (12%) still remain unprotected and provide critical habitat for over 17% of the national colobus population. The Diani and Shimoni forests in particular, are highlighted as key habitat for future colobus (and coastal forest) conservation initiatives. Local semistructured interviews and archival research into the historical distribution of the taxon in North Coast Kenya confirmed its occurrence (and subsequent range contraction) in the Kilifi District, with the last sightings occurring in the Arabuko Sokoke Forest in 1979. Differences in the settlement distribution, associated habitat loss and hunting preferences of the nine coastal tribes (Mijikenda) may explain why colobus have disappeared from the north coast, but persist in the south.