Quantifying Global Primate Road Deaths
According to the International Union for Conversations, two-thirds of the 522 primate species on earth are threatened and almost 90% have declining population trends. Furthermore, almost 20% are listed as threatened by roads and railroads.
As more roads are built (especially in developing countries), wild animals face habitat fragmentation, movement limitations, and life-threatening risks from bikes and cars. While these road accidents seem to be a small risk for global primate populations, it is highly neglected in the research. Some researchers collect data on these accidents, which helps us understand how much harm they are causing and how to keep the affected animals safe.
After researching different databases, research papers, anecdotal observations, and online news reports, the authors of this study created the Global Primate Roadkill Database (GPRD). As of February 2023, they collected over 2,800 roadkill incidents, involving at least 107 primate species, from 41 countries. The GPRD tries to include information about the data source, the primate species and their conservation status, the month/year of the incident, the location type, coordinates, and demographic details.
The authors provide descriptive details of the road collisions their database contains. Here are some of the facts:
- Species: Zanzibar Sykes’ monkeys were most affected (557 individuals), followed by vervet monkeys (371 individuals) and white-headed marmosets (215 individuals).
- Geographical Regions: Africa reported the most roadkill incidents (52%) followed by the Neotropics (33%). Looking at individual countries, Kenya had 1,026 deaths, followed by Brazil (788 deaths) and South Africa (302 deaths).
- Conservation Status: Nearly 76% of primate individuals reported as roadkill in the GPRD were listed as non-threatened species, while around 24% of the reported incidents involved species considered to be at risk of extinction. However, the authors point out that when a species is listed as “least concern,” this may be a result of a lack of data and not because they are truly safe from extinction risk.
The GPRD was created as a resource for recording and managing data on primate roadkill incidents. The authors believe it will serve as a valuable tool for future scientific analysis, and that it can assist conservationists and policymakers in assessing and planning conservation efforts. Therefore, they encourage citizen scientists and conservation professionals to contribute to the database with the goal of better protecting at-risk primates.
Various strategies are implemented globally to mitigate vehicle collisions with wild animals, such as creating animal-friendly underpasses and bridges, fencing, speed-reduction measures, and signage to warn drivers. The success of these measures depends on factors like location, habitat type, road type, and target species. The authors describe canopy bridges as one example of a mitigation measure proven effective in primate roadkill hotspots, promoting safe passage for arboreal primates. Road signs can also be effective when they incorporate local species to increase driver awareness.
Finally, this project highlights the importance of understanding how our infrastructure affects wild animals. While the majority of species involved in roadkill incidents are not threatened, that doesn’t mean we should neglect their suffering. Furthermore, as human infrastructure continues to expand, there is more of a risk that our roads and developments will pose a risk to species threatened with extinction.
https://www.mdpi.com/2076-2615/13/10/1692