干旱区生态环境知识资源中心

In the Oursi region (North of Burkina Faso) rodent populations live in four types of habitats. In habitats where food is available all year round (unrestricted habitats) reproduction of Mastomys huberti is continuous. In habitats where food is available throughout the year, but in which Arvicanthis niloticus face a period of flooding (flooding habitats), non-trophic factors (daylength, temperature, air humidity) induce a sexual rest period before the arrival of the flooding period. In habitats where food is seasonally available with an annual rich-food period lasting twice as long as the annual restricted-food period (semi arid habitats), reproduction of Mastomys erythroleucus and Taterillus gracilis is mainly related to seasonal variations in the diet. When available food is widely seasonal, with an annual restricted-food period twice as long as the rich-food period (arid habitats), reproductive cessation is mainly related to the appearance of a restricted-diet in M. erythroleucus, Gerbillus nigeriae, Taterillus petteri and Acomys sp., while the reproductive onset is related to non-trophic factors, which permit it to anticipate the arrival of the rich-food period. The ecological significance of these regulatory mechanisms is discussed.