Distribution of tree hyrax (Dendrohyrax validus validus True) on Mt Kilimanjaro, Tanzania

Abstract

SummaryDistribution of Dendrohyrax v. validus True which inhabits the forest belt of Mt Kilimanjaro, Tanzania, is discussed along with factors influencing this distribution. During December 1972 data were collected from the northern, eastern, southern and western slopes at 2000, 2310 and 2620 m a.s.l. to discover the effect of aspect and altitude on vegetation in relation to the densities of the tree hyrax. Using point‐centred quarter method (PCQ) the area around each tree was inspected for recent and abandoned defaecation sites; the tree species and its circumference at breast height were also recorded.Apparent densities of hyrax, as reflected by the density of defaecation sites, were higher on the southern and western slopes (av. twenty‐three and thirteen hyrax/ha) although a density of seventy hyrax/ha was obtained for the northern slope at the 2620 m elevation. The eastern slope was poorest with only one defaecation site recorded. Higher densities were obtained for the 2310 m elevation indicating less disturbance of this belt through logging and also showing the influence of Ocotea usambarensis Engl, on the southern and Nuxia congesta Fres. on the western slopes which are abundant at this elevation. The tree hyrax showed definite preference for certain tree species and for the larger individuals.Since food is not limiting, it is suggested that the availability of shelter, strong preference for solitary living, and the inability to withstand rigorous environment limit the density of hyrax within the forest, as well as providing a possible explanation for the inability of this hyrax to venture far outside the forest.