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bioRxiv · 10.64898/2026.08.22.746414

Predation of small nocturnal primates (Microcebus) on Madagascar; insights into predator preferences in Andohahela National Park

Abstract

Predation is a major selective force shaping lemur behaviour and population dynamics, yet direct observations remain rare, particularly for small nocturnal species. Here, we document predation on mouse lemurs (Microcebus spp., Cheirogaleidae) in Andohahela National Park, south-eastern Madagascar, and using complementary evidence from radio-telemetry and owl pellet analyses. Two radio-collared individuals were confirmed as prey of endemic snakes, Ithycyphus oursi and Madagascarophis meridionalis (both Pseudoxyrhophiidae), representing the first documented records of Microcebus predation by these species. Examination of owl pellets and prey remains from three sites and from three owl species revealed a single predation event by Asio madagascariensis (Strigidae), likely involving M. tanosi, no evidence of mouse lemur predation by Tyto alba (Tytonidae) despite high local prey availability, and a single and first predation record from Athene superciliaris (Strigidae). Material from A. superciliaris roosts was otherwise dominated by invertebrates, indicating that primate predation is likely opportunistic. Together, these findings expand the known predator guild of mouse lemurs and suggest that snake predation is rarely detected, and its contribution to mouse lemur mortality and population dynamics is likely underestimated. Our findings demonstrate how combining behavioural field observations with dietary evidence can uncover otherwise undetected predation events and clarify predator prey relationships in nocturnal primates.

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BibTeXRIS

Hyde Roberts, S., Segami, J. C., Harinala, V. J. N., Rajemison, B., Rasoarinoro, E., Goodman, S. M., Yoder, A. D.. 2026-08-26. Predation of small nocturnal primates (Microcebus) on Madagascar; insights into predator preferences in Andohahela National Park. https://doi.org/10.64898/2026.08.22.746414

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