Ecological and Reproductive Correlates to Range Use in Red-Bellied Lemurs (Eulemur Rubriventer) and Rufous Lemurs (Eulemur Fulvus Rufus)

Abstract

In this paper, I describe how ecological variables (diet, food availability, patch characteristics) and variables unrelated to food availability such as reproduction and territoriality, affect daily and long-term ranging patterns in two primate species in southeastern Madagascar: the rufous lemur (Eulemur fulvus rufus) and the red-bellied lemur (Eulemur rubriventer). Daily path lengths (DPL), home range size, and the distance traveled between patches were compared and contrasted between lemur species. Rufous lemurs ranged further on a daily and long-term basis than red-bellied lemurs. Group ranges overlapped extensively and rufous lemurs did not defend home range borders. In contrast, red-bellied lemurs maintained exclusive use of their home range and actively defended boundaries. Additionally, rufous lemurs used more scattered patches and traveled further between these patches than red-bellied lemurs Ranging patterns in both lemur species were not correlated with food availability but were influenced by three seasonal variations in diet: the number of food patches visited, dietary diversity, and the number of feeding bouts. Rufous lemurs traveled furthest when each of these variables was highest and coincided to the same time period when females were lactating. A similar seasonal peak in red-bellied lemurs ranging patterns was not observed although they traveled further when daily diet was more diverse. It is suggested that the presence of several reproductively active females in rufous lemur groups may influence food choice and consequently, ranging patterns. In contrast, red-bellied lemur’s territoriality may limit group movements and constrain daily and seasonal ranging.