Habitat-specific diversity and distribution of small mammals on University of Ilorin campus, Ilorin, Nigeria

Abstract

Small mammals, though not a formal taxonomic group, represent one of the most abundant and ecologically significant components of terrestrial ecosystems. The present study investigated the diversity of non-volant small mammals across contrasting habitats within the University of Ilorin campus. Sampling was conducted across five locations representing a gradient of ecological and anthropogenic conditions (the farmlands and grassland/shrubland adjoining administrative buildings, teak plantations, poultry farms and the botanical garden). Sampling followed a standardised live-trapping protocol as part of a longitudinal assessment conducted between 2023 and 2025. Across the three years, six genera of small mammals were Crocidura, Grammomys Heliosciurus, Mastomys, Mus and Rattus belonging to seven species. The 2023 genera comprised Mus spp., Mastomys sp., Rattus sp, Grammomys sp., and Crocidura spp., whereas the 2024 genera include Mus spp, Mastomys sp., Crocidura sp., and Heliosciurus sp. Only Mus sp individual was recorded in the teak plantation in 2025. The Botanical Garden supported the greatest species richness due to their vegetation and stable microclimates, whereas more disturbed environments, including poultry farm and administrative areas were dominated by adaptable generalists such as Mus spp, Mastomys sp, and Rattus sp. The 2025 genus in the teak plantation further emphasised the influence of habitat quality, with only one individual captured in the unburnt section and none in the burnt area, reflecting the limited resources and simplified structure typical of teak monocultures, particularly following fire disturbance. The study demonstrates that small mammal diversity within the University of Ilorin campus is closely linked to habitat structure and the extent of human disturbance.