The 85th Annual Meeting of the American Association of Physical Anthropologists (2016)

Are Roads a Dispersal Barrier for Microcebus?


1Department of Anthropology, University of Toronto, 2Department of Animal Biology, University of Antananarivo

April 16, 2016 , Atrium Ballroom A/B Add to calendar

Road ecology is an underutilized line of inquiry within primate conservation biology. While roads are often assumed to be dispersal barriers in primates there is little empirical testing of this assumption. We tested the hypothesis that Route National #4, a paved highway, was a dispersal barrier for two species of mouse lemurs (Microcebus murinus and M. ravelobensis) in Ankarafantsika National Park in NW Madagascar. We conducted a capture-mark-recapture experiment from June to August 2015 in which we established three sites with pairs of parallel transects 25m apart; two sites adjacent to Route National #4 and one within intact forest without a dispersal barrier. After 2294 trap nights we caught 123 individual mouse lemurs 1054 times. We detected 18 crossings from 9 individuals on highway transects, compared with 157 crossings from 27 individuals within the intact forest. Only male M. ravelobensis were captured on both sides of the highway and only in the vicinity of an arboreal crossing, such as two trees on either side of the highway with a canopy connection. No females of either species crossed the highway during our study period. One identified M. ravelobensis was killed by a vehicle in an apparent attempt to cross the highway. M. ravelobensis were inhibited in their movements across the highway, but dispersal was still possible across this potential barrier. Our study presents some of the first results on the effects of roads in Malagasy primates and showcases species-and-sex-biased effects of roads as dispersal barriers.

Department of Anthropology, University of Toronto; Natural Sciences and Engineering Research Council of Canada; Primate Conservation Inc.; Sigma Xi