Patterns of mammalian roadkill in the Serengeti ecosystem, northern Tanzania

Roads that traverse through protected areas if not well managed can have adverse impact on wildlife such as road-kills which is of global conservation concern. Though mammalian road-kills have been reported in different protected areas worldwide, very little information on the problem is available in the Serengeti ecosystem. This study employed both cross sectional observation and opportunistic encounter methods to determine the patterns of mammalian road-kills along the existing gravel road networks in the area. The results indicated that 29 mammals with encounter rates of 0.016 animals/kilometer including herbivores (75.9%), carnivores (13.8%) and omnivores (10.3%) were found killed more frequently on good roads, probably because of over speeding behavior by drivers. Mammals with small body sizes (<10.0 kg, 44.8%) predominantly Cape hares ( Lepus capensis, 31.0%) and Thomson gazelle ( Eudorcas thomsonii , 27.6%) were most frequently killed probably because they are less avoided by motorists than larger mammals; and also, smaller mammals move slowly in crossing the roads than larger mammals, which increases the chances of being hit by vehicles. Cape hares and Thomson gazelles are more abundant species in the Serengeti and their behavior of foraging on road verges and frequently crossing roads to access resources in the area is additional risk. The study findings recommend for high penalties to over speeding drivers and placing wildlife warning signs on the roadside, and education to drivers to change behaviour and reduce road-kills.