Is the southern patas monkey Erythrocebus baumstarki Africa's next primate extinction? Reassessing taxonomy, distribution, abundance, and conservation

The Critically Endangered southern patas monkey Erythrocebus baumstarki, thought to be endemic to Tanzania, has been resurrected to species level based on its geographic isolation, and on the coloration and pattern of its pelage. This study presents the first evidence for E. baumstarki in Kenya and reviews its historic and current geographic distributions based on the literature, museum specimens, online platforms, responses to requests for site records, and our own fieldwork. The distribution of E. baumstarki in the early 20th century was roughly 66,000 km(2). This has declined about 85% to around 9700 km(2) at present (post-2009). The current Extent of Occurrence is only about 2150 km(2). This species was extirpated from Kenya in about 2015 and from the Kilimanjaro Region in Tanzania in about 2011. At present, E. baumstarki appears to be restricted to the protected areas of the western Serengeti, with the western Serengeti National Park being the stronghold. The number of individuals remaining is probably between 100 and 200, including between 50 and 100 mature individuals. The ultimate threat to E. baumstarki is the very rapidly increasing human population, while the main proximate threats are the degradation, loss, and fragmentation of natural habitats, and the related competition with people and livestock for habitat and water, particularly during droughts. Other problems are hunting by poachers and domestic dogs, and probably loss of genetic variation and climate change. This article provides recommendations for reducing the threats and promoting the recovery of E. baumstarki. We hope this article heightens awareness of the dire conservation status of E. baumstarki and encourages an increase in research and conservation action for this monkey.

Automated summary

The Critically Endangered southern patas monkey, Erythrocebus baumstarki, has been reclassified as a separate species based on geographical isolation and physical characteristics. Its population has declined significantly due to threats such as human encroachment, habitat degradation, and climate change, leading to a current population estimate of 100 to 200 individuals mainly concentrated in the western Serengeti National Park. Urgent conservation actions are needed to protect this species.