Exploratory Insights on Nonvolant Mammals, Their Habitat Associations, and Taxonomic Relevance in Rugezi Marsh: A High-Altitude Tropical Montane Wetland in Rwanda

Majyambere M.; Nsabimana A.; Niyodushima P.; Hishamunda P.; Rurangwa M.L.; Masengesho P.; Ruhagazi D.; Kamatenesi J.; Sánchez-Vendizú P.; Erkenswick G.; Libke Z.; Pellón J.J.; Nsengimana O. · International Journal of Zoology (2026) · DOI: 10.1155/ijz/5594315

Resumen

We surveyed nonvolant mammals as part of a rapid biodiversity study of the high-altitude Rugezi Marsh, a Ramsar site in Rwanda, during 42 days across two seasons in 2023. Field methods included 30 days of active searching and live trapping (Sherman, pitfall, and cage traps), and 27 days of camera trapping. Sampling incorporated six distinct habitats forming a gradient of decreasing water saturation: saturated zone, papyrus habitat, edge, grassy habitat, buffer zone, and island. Morphological identification of specimens was performed with field keys from direct observation and photographs, with small-mammal classification complemented by DNA barcoding of the mitochondrial genes, Cytb and COI. We recorded 28 distinct mammal taxa: 17 identified species including 8 rodents, one shrew, and 8 carnivores; 2 rodents and a mole tentatively assigned to species; and 8 small mammals assigned to genus only, including 5 shrews and 3 rodents. This study documented the data-deficient (DD) rodent Lophuromys stanleyi, two near-threatened (NT) otters, and the shrew Sylvisorex lunaris (NT). Field observations provided preliminary insights into the impact of wetland habitat conditions and disturbance on mammals; specifically, slightly disturbed, semiwet zones with tall grasses supported higher species richness. Here, preliminary insights into nonvolant small-mammal relative abundances (especially shrews and rodents) were inferred from rapid assessment records. The species records were compared to prior mammal results from other wetlands, with a focus on Africa and neighboring countries. The results reveal substantial gaps in the taxonomic knowledge of nonvolant small mammals, especially shrews, inhabiting tropical wetlands. Given the ecological dependencies between tropical marshlands and nonvolant mammals, high-altitude tropical wetlands should become a focal area of research investigation in Rwanda and across tropical Africa. Copyright

Instituciones: Universidad Nacional Mayor de San Marcos