Land-use change and small-mammal diversity in and around African mountain forest reserves: consistent loss of habitat specialists and critical gaps in altitudinal, long-term, and landscape-scale research- a review

Abstract

Anthropogenic land-use change, such as agricultural intensification, selective logging, overgrazing, altered fire regimes, urbanisation, plantation forestry, and habitat fragmentation, have consistently favoured ecologically generalist small mammals while driving marked declines or local degradation of habitat-specialist species (particularly forest-dependent rodents and shrews) across Africa. This systematic review synthesised 37 independent field studies (2002–2021) and reveals a striking continent-wide pattern: natural and lightly disturbed habitats sustain higher small-mammal richness and specialist taxa, whereas intensive disturbance shifts assemblages toward a small set of generalist species, often with seasonal peaks tied to rainfall or crops. Despite this convergence, virtually all studies share the same critical methodological gaps: no altitudinal transects, no long-term (multi-year) monitoring, no landscape-connectivity or matrix-permeability analyses, limited multi-seasonal replication, and no assessment of population sustainability or resilience. Consequently, reported specialist declines may reflect temporary dispersal or seasonal lows rather than irreversible extinction, while the long-term viability of dominant generalists remains unknown. The current evidence base is therefore predominantly short-term and snapshot-based, severely limiting its predictive value for conservation under accelerating land-use and climate change. Robust future research requires routine incorporation of elevational gradients, multi-annual monitoring, landscape-scale connectivity analyses, full seasonal coverage, and explicit tests of population persistence to secure Africa’s small-mammal diversity.