Exploring the Effects of Habitat Fragmentation on Ranging and Behavioral Patterns of Propithecus coquereli in the Mahamavo Dry Forests of Northwestern Madagascar

Abstract

The decline in population density of the Coquerel’s sifaka (Propithecus coquereli) is indicative of observed trends among different taxa, which are directly related to the high levels of habitat fragmentation that are characteristic of numerous forests in Madagascar. As continuous forest habitats have progressively shrunk and many forest patches have been assimilated by village areas, an increasing amount of sifaka have adapted to secondary and degraded habitats. My research aims to understand the most common responses of P. coquereli to characteristics of degraded environments. To assess this, I tested the effects of prevalence of non-native (exotic) tree species and distance from the forest edge on behavioral patterns, Daily Path Length, and home range size of different sifaka groups. My study found that prevalence of exotic tree species and distance from the edge had conflicting effects on the activity budgets of P. coquereli. However, groups closer to interior forest areas had larger home ranges and higher Daily Path Length values than those ranging near the forest edge. This relationship was inverted when measuring ranging patterns across prevalence of exotic trees: Groups with a higher percentage of non-native trees in the habitat were more restricted in their ranging than groups living near a higher percentage of native trees. Future research should continue to investigate how these gradients affect behavior percentages of P. coquereli, as well as further develop those studies to include analyses of health indicators in sifaka groups.