Composition and seasonality of rodent diet in Chimit Kola, Blue Nile Gorge, Ethiopia

Abstract

A study on the composition and seasonality of rodent diet was carried out during 2020–2022 years in Chimit Kola to determine the type, relative proportion and seasonality of food items consumed. A total of 166 stomach contents that belong to six rodent species (Mastomys awashensis, Acomys louisae, Arvicanthis raffertyi, Lophuromys simensis, Gerbilliscus sp. and Lemniscomys macculus) were investigated. Parametric and non-parametric analyses of variance were used to test the difference. Leaves and stems, seeds, invertebrates, fruits and unidentified food matters were the food items identified in the stomach contents of rodents. There was a significant variation in food items consumed among rodent species. Arvicanthis raffertyi and L. macculus consumed more leaves and stems whereas L. simensis, A. louisae and Gerbilliscus sp. mostly fed on invertebrates. Mastomys awashensis consumed relatively more seeds (30%) than any other rodent species (ranging from 14 to 28%). Acomys louisae, L. simensis and Gerbilliscus sp. consumed more leaves and stems during the dry season and invertebrates during the wet season. Similarly, A. raffertyi consumed more leaves and stems during the wet season and seeds during the dry season. However, the diet of M. awashensis and L. macculus and some food items (fruits and unidentified food matters) of most rodent species were similar between seasons. Mastomys awashensis significantly consumed a higher proportion of seeds in the fallowland (44%) than in other habitats (ranging from 19 to 31%). Similarly, A. louisae and L. macculus consumed a significantly higher proportion of invertebrates in bushland (53%) and riverine forests (48%) than in other habitats (ranging from 16 to 47%), respectively. The present finding concluded that these rodent species are diet generalists, feeding on a variety of available resources depending on seasons and habitats. The study documents the diet composition of these rodent species for the first time. Thus, the management and conservation of these rodents should be in consideration of their feeding habits and factors that influence their diets.