Conservation genetics of fragmented lemur populations in Madagascar

The golden-crowned sifaka (Propithecus tattersalli) in the Daraina region

 

Ph.D project under the supervision of Lounès Chikhi and Brigitte Crouau-Roy

Since habitat fragmentation reduces the size of habitat patches and decreases their level of connectivity, this process is among the greatest threats faced by species in tropical regions.
Here, we studied the case of the golden-crowned sifaka (Propithecus tattersalli), a rare and threatened species of lemur from northeastern Madagascar, whose populations are only found in a small and highly fragmented forest habitat.
This socially-organized species, endemic to the Daraina area, was only discovered twenty years ago (Simons, 1988) and little is known about its resiliency to the growing forest clearing.

To provide relevant information to set up appropriate conservation strategies for this species :

 

1) I studied its distribution and assessed the density of its main populations

 

2) I characterized its global genetic structure isolating new specific microsatellites and collecting faeces from 403 putative individuals (118 social groups) sampled in the whole distribution area.

By combining field observations, density estimations, spatial and population genetic analyses, I studied how landscape structure and composition (i.e. natural and anthropogenic features such as roads, rivers, or habitat connectivity, etc.) influence patterns of gene flow among resources patches.

 

I also used neutral genetic data to address issues related to the demographic history of populations with a particular emphasis on the detection, quantification and dating of population collapses related to the habitat  loss and fragmentation. The aim was to provide relevant information to set up appropriate conservation strategies for an endangered animal species living in highly heterogeneous and changing environments. I characterized the global genetic structure of the species of interest isolating new specific microsatellites and using non-invasive DNA extracted from faecal material I collected on the whole distribution area.

In collaboration with Pr. Pierre Taberlet (LECA, Grenoble, France), I am currently conducting a project whose aim is to characterize the diet of the golden-crowned sifaka by combining DNA-barcoding and the high-throughput sequencing of the plant DNA within the faecal pellets  (using SOLEXA pyrosequencing). This project involves large-scale sequencing approaches and the analysis of large DNA sequence datasets.