Outside protected areas in Ethiopia, there is a lack of information concerning mammalian diversity and ecology. Consequently, the findings of the research on large mammals at Geremba Mountain constitute one of the steps towards a continuing effort to document the diversity and distribution of Ethiopian mammals. The survey was conducted to investigate the species composition, relative abundance, and population structure of large mammals at Geremba Mountain fragment from August 2017 to February 2018, covering both dry and wet seasons. Direct (sighting) and indirect (scat) survey techniques were employed using systematically established transect lines and sampling plots, respectively. Transects and plots were established across three dominant habitat types (modified dry ever green Afromontane forest, alpine bamboo forest, and Erica scrubland). A total of 10 large mammal species were recorded including two endemic mammals, namely, Chlorocebus djamdjamensis and Tragelaphus scriptus meneliki. There was a statistically significant difference in the abundance of species among habitat types at Geremba Mountain. The highest diversity index was recorded in the alpine bamboo forest habitat (D = 7.142, H′ = 2.052), and the Erica scrubland had the lowest. Papio anubis was the most abundant species while Felis serval was the least abundant species. The populations of most of the species were characterized by more adult and more female individuals. However, promising young individuals of the endemic mammals (C. djamdjamensis and T. s. meneliki) and Papio anubis were recorded. The mountain fragment is an isolated island that is totally disconnected with other fragments in the region, so attempts should be made to connect the fragment with other fragments using wildlife corridors.

There is a lack of information on mammalian faunal resources of remote forests in Ethiopia; as a result, the findings of the research on large wild mammals at Nensebo forest is one of the steps in a continuing effort to document and describe the diversity and distribution of Ethiopian mammals in remote and less accessible forests. The survey was conducted to assess the species composition and relative abundance of large mammals. Two standardized survey techniques, direct (sighting/hearing) and indirect (scat/footprint), were employed using systematically established transect lines and field plots in two dominant habitat types (modified moist Afromontane forest and intact moist Afromontane natural forest) of the study area. A total of 16 species were recorded including two endemic mammals, namely, Tragelaphus buxtoni and Tragelaphus scriptus meneliki. Abundance of species among different habitat types was not significantly different (χ2 = 0.125, df = 1, p > 0.05 ), and Colobus guereza was the most abundant species. In contrast, Felis serval, Panthera leo, and Tragelaphus buxtoni were the least abundant species. The highest diversity index was recorded in the natural forest habitat (H′ = 2.188), and the modified forest had the lowest diversity index (H′ = 1.373). There is an urgent need to minimize threats and mitigate impacts.