Examining vertebrate road mortality on highways passing through protected areas of eastern Ethiopia

Abstract

Highways bisecting protected areas can have adverse impacts on wild animals. Many studies around the world have investigated the intensities of roadkill resulting from such highways and the subsequent conservation impacts. However, there have been limited studies undertaken in developing countries in this regard. We investigated road-related mortality of three taxonomic groups (birds, mammals, and reptiles) on six roads in eastern Ethiopia that bisect four protected areas. We collected roadkill occurrence data in both dry and wet seasons by undertaking 34 systematic driven road surveys over a 5-month period. A total of 128 roadkill were recorded comprising 44 species belonging to 24 families. We recorded more bird and mammal roadkills, making up 46.9.% and 45.3% of the total samples, respectively. Out of the 44 species detected, 79.6% were of least concern, while 18.1% were vulnerable, i.e., near threatened and endangered species, while 2.3% were critically endangered. Diurnal species constituted the majority of roadkill detected (75%), followed by nocturnal (18.2%) and crepuscular (6.8%). Most records of roadkill (64.8%) were encountered in roads adjacent to protected areas, highlighting the potential threat that roads pose on wildlife within protected areas of Eastern Ethiopia. Our study is aimed at adding to the baseline of impacts of roads on wildlife in developing countries. Further study of spatial and temporal patterns of roadkill on the current study roads and other roads in the country will assist with a greater understanding of the impacts of roads in Ethiopia and allow appropriate mitigation measures to be proposed.