Population dynamics of Arvicanthis niloticus (Rodentia: Muridae) in Kenya

摘要: The population dynamics of the Grass rat Arvicanthis niloticus were studied in relation to their diet and climate Nakuru district Kenya between September 1980 May 1982. Numbers study area low at end with groups animals isolated patches grassy habitat. Local populations declined some became extinct during first half 1981. Breeding began April, one month after start rains, but a small initial high juvenile mortality, numbers did not increase significantly until September, when born earlier season old enough reproduce. This second generation reproduction was probably very important survival over following dry adult mortality estimated 15% per month. Reproduction facilitated by nutritious diet, consisting mainly young grasses early seeds later on. Seed production itself related rainfall as that towards 1981, breeding ceased. considerably more numerous then than year previously, difference being ascribed longer rainy experienced 1981 1980. density favourable habitats increased immigration from less suitable areas January March 1982, study. resumed rains. Peak recorded middle season, few crops ground. They would only become serious pest agriculture if they still abundant months later. Expansion could result harvest time, August or September.