Relative Densities of Mammals in Response to Different Levels of Bushmeat Hunting in the Udzungwa Mountains, Tanzania

Bushmeat hunting constitutes the most immediate threat to wildlife populations in the Udzungwa Mountains of the Eastern Afromontane biodiversity hotspot. This study assesses the impact of hunting by comparing densities of mammalian species between the little hunted West Kilombero Scarp Forest Reserve (WKSFR), the medium-hunted Udzungwa Scarp Forest Reserve (USFR) and the intensively hunted New Dabaga Ulongambi Forest Reserve (NDUFR). Of the 22 species recorded, 20 were present in WKSFR, 17 in USFR and 12 in NDUFR. Most large species (>40 kg.) were absent from hunted areas, while medium-sized species were reduced more than smaller species. Few traces of Abbott's duiker were observed in hunted areas and bush pig was reduced by more than 85% in hunted areas. Hunting appears to have little effect on relative abundance of primates, blue duiker, Harvey's duiker, aardvark, eastern tree hyrax, and giant pouched rat in USFR, at least for those areas surveyed. In NDUFR relative abundance of most mammals are reduced compared to the less hunted reserves. The exception is red colobus which were no less abundant than USFR. However in NDUFR, transects were placed in the best quality habitat for these habitat-sensitive monkeys, thus emphasising the additional role of habitat degradation. The effect of hunting appears to be proportional to the size of the species and the intensity of hunting, although effects of life history strategy, forest fragment size, isolation, and previous logging cannot be excluded. Reduction of hunting levels are paramount to the survival of large bodied species in USFR and for the continued presence of most species in NDUFR. This study furthermore constitutes an important baseline for monitoring the effect of current efforts to implement joint forest management in the Udzungwa Mountains