A 5-YEAR POPULATION STUDY OF AN ASSEMBLAGE OF SMALL MAMMALS IN SOUTHEASTERN BRAZIL

A five-year capture-mark-recapture study of small mammals was carried out in a Brazilian coastal shrubby vegetation (restinga). Five species of small mammals (rodents and marsupials) were trapped and had their population dynamics characterized. Akodon cursor and Philander opossum presented the highest population densities, which were correlated chiefly with recruitment. They displaiyed frequent population fluctuations with high coefficients of variation, low survivorship rates most of the time and short residence times. Proechimys iherigi was characterized by stable population densities, high survivorship rates and long residence lime. Didelphis aurita and Metachirus nudicaudatus presented low densities, disappearing occasionally from the study area, and they can be characterized by the absence of permanent population center. No regular pattern of seasonal population fluctuations was detected for any species in the assemblage, but populations seem to present pluriannual patterns of fluctuation. The marsupials reproduce seasonally from late winter until the end of the summer. Rodents did not show a clear reproductive season. The mammalian fauna of the Restinga de Barra de Marica seems to be a subset of the Atlantic Forest fauna, impoverished by its habitat configuration.