Seasonality and behavioral energy strategies in (Microcebus berthae and M. murinus)

Abstract

To survive and reproduce successfully in highly seasonal regions, animals must balance their energy budgets during lean seasons. We conducted a comparative study of two sympatric mouse lemur species to identify species-speci fic energy saving strategies for coping with seasonality and evaluated their consequences for female fitness. Since August 2002 we captured, marked and recaptured individuals of coexisting populations of Microcebus berthae and M. murinus in Kirindy Forest and recorded activity by direct observations of radio-collared females. The species differed in their seasonal activity patterns: female M. berthae maintained high activity levels throughout the year, whereas female M. murinus largely ceased activity during the cold dry season. In M. berthae , low survival restricted female reproductive potential. Consequently, females maximized the condition in which they entered the reproductive season. In contrast, M. murinus females maximized survival but entered the reproductive season in poor condition. Thus, mouse lemur species subjected to the same environmental conditions show different species-speci fic behavioral energy strategies to cope with pronounced seasonality.