Season and habitat affect diversity, abundance and reproductive state of small mammals near Lake Abaya, Ethiopia

This study investigated the spatio-temporal association of small mammals in human-modified habitats. Small mammals were sampled using Sherman traps along 200 m transects (with one trap at every 10 m interval) in each of four habitats (cropland, forest patch, scrubland and wetland) replicated twice. Additional trapping was carried out in rural settlements comprising of eight homesteads, with five traps per homestead. Trapping was conducted in three sessions during the agricultural seasons: rainy (October), off-rain (December) and dry (February) over two years (2018 and 2019). In each session, trapping was carried out for three consecutive nights. A total of 497 small mammals belonging to 12 species from four families (Soricidae, Macroscelididae, Gliridae and Muridae) were captured. Murine rodents accounted for 99.4% of the animals with Mastomys erythroleucus (58%) being the dominant species. The scrubland had the highest small mammal species diversity while the cropland had the lowest. M. erythroleucus was not strongly associated with any spatio-temporal parameter and scored majority of seasonally reproducing individuals in the cropland, signifying its pest importance. Though disconnected from protected areas, habitats such as the scrubland harbor diverse small mammal species (including a vulnerable-endemic species, Grammomys minnae), suggesting the habitats' significance for ecosystem functioning and conservation.