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This review examines the impact of rainfall on rodent outbreaks in Sub-Saharan Africa.It aims to show that under changing climate,outbreaks may become more difficult to predict.Strong association occurs between severe rodent outbreaks and rainfall.Hardly any serious population outbreaks occur during the dry seasons and years with sub-optimal rainfall levels.Studies in Sub-Saharan Africa indicate spatial and temporal variations in population dynamics and survival that is clearly driven by a bottom–up trophic influence but also that abundance is determined by intrinsic characteristics of the involved species.Reproduction and the duration of the breeding season,survival,recruitment and growth seem to respond to rainfall which determines the quantity and quality of primary productivity.Most studies show absence of reproductive activity during the food scarce season,and that maximization of reproductive activity occurs during the wet season and early in the dry seasons.Factors including cropping patterns and vegetation cover and local climatic conditions,which may vary within and between years,also influence population dynamics.The major outbreak species in Sub-Saharan Africa,Mastomys natalensis,is able to take advantage of the favourable conditions in the wet season to boost survival and recruitment and therefore increase in numbers at higher rates than other species.With climate change expected to cause irregularity in the amount,duration and inter-annual variations in rainfall,prediction of occurrences of rodent outbreaks may become more difficult in sub-Saharan Africa.Therefore we need to apply ecologically-based mechanisms to deal with unexpected surges of rodent pest populations.