Dietary patterns of a crop pest mammal species (Mastomys natalensis) inhabiting agro-field-protected area interface in Western Serengeti, Tanzania

Rodent pest control is challenging because of complex dynamics of their populations. We investigated the influence of seasons and habitats on food categories and diet breadth of Mastomys natalensis (Smith, 1834) through analysing 107 stomachs collected in Kijereshi Game Reserve and Nyamikoma village in western Serengeti-Tanzania, using kill traps. Plant materials (41%) and invertebrates (39.1%) dominated the animal’s diet in different seasons and habitats. Numerically, during the wet season, invertebrates dominated in the fallow land (90.0%) followed by the wooded grassland (83.3%) and maize crop fields (76.2). Plant materials were in large quantity in maize crop fields (27.6%) and least in in the wooded grassland (16.7%). Furthermore, seeds/grains were eaten more in maize crop fields (20.7%) as compared to fallow land (19.3%) and the wooded grassland (6.9 %). In contrast, in the dry season, plant materials occurred at a higher frequency in maize crop fields (85.7%) followed by fallow land (60%) and lastly the wooded grassland (50%). Seed/grain featured more in the diet in maize crop field (75%) followed by fallow land (44.4%) and lastly by the wooded grassland (36.4%). Invertebrates occurred with higher frequency in the wooded grassland (72.7%) followed by fallow land (66.7%) and lastly by maize crop fields (58.3%). Statistical tests on the effects of habitats and seasonality on the dietary patterns of M. natalensis, revealed non- significant effect of each individual variable respectively (p = 0.43) and (p= 0.81) respectively. Effect of seasonality and habitats on M. natalensis food categories were observed on plant materials but not in seeds/grains and invertebrates. The animal ate plant materials and seeds/grains substantially in the maize crop fields, suggesting that it is a potential pest. Therefore, combined management actions are needed which include clearance of bushy fallow lands and rodenticides application but preventively and remedially when there is a need.