Abstract # 905 Poster # 62:

Scheduled for Thursday, August 18, 2005 07:00 PM-09:00 PM: (Cambridge/Oxford Room) Poster Presentation

Predation avoidance may affect habitat preference of the brown mouse lemur (Microcebus rufus) in Ranomafana National Park, Madagascar

N. Musto1, A. M. Deppe2, L. Randrianasolo3 and P. C. Wright1
1Stony Brook University, Department of Anthropology, Stony Brook, NY 11794, USA, 2Interdepartmental Doctoral Program in Anthropological Sciences, Stony Brook University, 3Centre ValBio, Ranomafana, Madagascar
     Mouse lemurs are subject to heavy predation by raptors, carnivores and snakes, and predation rates may be as high as 25 percent. Being small, nocturnal and solitary the best predator avoidance strategy for a mouse lemur may be concealment by dense vegetation. We analyzed botanical plots (5x5m) set around 24 Microcebus rufus trap sites between September and November in Ranomafana National Park, Madagascar. For each plot, dominant plant species, tree height and tree diameter at breast height (DBH), distance from trail, trap height and canopy-cover were recorded. For each trap, frequency of mouse lemur capture was calculated. When traps were ranked by capture success results showed that mouse lemurs were 25 percent more frequently caught in areas with low average tree height of 6-8m and 47% more frequently in plots with a low average DBH of 4-6cm. Capture rate was highest at 64.5% in plots dominated by invasive guava (Psidium cattleianum) followed by the endemic fohaminasity (genus Psychotria). Characteristics of both plants include the ability to grow in high densities and to produce high-canopy and sub-canopy density. Guava is especially characterized by many small side branches, creating dense tangles. These characteristics probably make it difficult for both terrestrial and aerial predators to approach unnoticed and mouse lemurs may thus prefer such areas. Supported by PCI and PAF.