The impacts of road infrastructure on wildlife are of mounting concern. Amidst a growing body of literature on vehicle–wildlife collisions, few studies focus on primates. We examined a long-term dataset (2000–2018) of community-reported welfare cases for four species of monkeys: colobus (Colobus angolensis palliatus), Sykes’s monkey (Cercopithecus mitis albogularis), vervet (Chlorocebus pygerythrus hilgerti), and baboon (Papio cynocephalus cynocephalus). We analyzed collision rates using annual census data along a 10-km road section through the suburban town of Diani, Kenya. Vehicle–monkey collisions represented 705 of 1896 cases (37%), which was the most common anthropogenic cause of injury and death. The mean number of monthly vehicle–monkey collisions was 3 (range 0–10), and 83% of collisions led to death of the monkey. We found 1) higher degrees of terrestrialism were associated with lower number of collision cases; 2) no differences in the collision rates between juveniles, subadults, and adults across species, but collisions involving infants occurred at lower rates; 3) similar collision rates for female and male colobus and baboons, whereas Sykes’s monkey females and vervet males were more frequently involved in collisions than the other sex; 4) no correlation between the number of hotel bed-nights (a measure of tourist numbers) and vehicle collisions; and 5) drier days correlated with increased rates of vehicle–monkey collisions across all species. This study highlights the risks of roads for monkeys, and that collision rates vary with species, age class, and, in some species, sex and that rainfall is one factor that affects these rates.
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We thank the Government of Kenya, Kenya Wildlife Service and the National Commission of Science, Technology and Innovation for supporting this research. This research was possible only because members of the Diani community responded to primate welfare cases. We thank Colobus Conservation, a PASA member sanctuary, for the use of the animal welfare dataset. We also thank Johnno Beakbane for the use of the rainfall dataset and Rachel Stokes for her input into the draft. Though we did not receive funding to carry out this research, Columbus Zoo, the International Primate Protection League (IPPL), and the African Network for Animal Welfare (ANAW) provide ongoing support for Colobus Conservation’s emergency primate response service. The contributions of the anonymous reviewers and especially of the editor-in-chief, Dr. Joanna Setchell, were important to the development of this article.
Handling Editor: Joanna M. Setchell
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Cunneyworth, P.M.K., Duke, J. Vehicle Collisions Among Four Species of Monkeys Between 2000 and 2018 on a Suburban Road in Diani, Kenya. Int J Primatol 41, 45–60 (2020). https://doi.org/10.1007/s10764-020-00135-w
- Road-crossing behavior
- Road mortality
- Wildlife–vehicle collision