COS 231-6 - The influence of vegetation type on the distribution of Jolly’s mouse lemur, Microcebus jollyae, in Kianjavato, South Eastern Madagascar

Background/Question/Methods

Madagascar’s landscape had changed drastically in the past 2000 years. Many areas which were forested have been modified for human activities. Most species of lemurs struggle to survive in modified land, which has led to 98% of lemur species being threatened with extinction. Mouse lemurs, Microcebus, are a genus that has been found in a variety of habitats from pristine forests to agricultural fields, and even peoples’ gardens. Our focus is on the Endangered Jolly’s mouse lemur, Microcebus jollyae, which is microendemic and found only in and around Kianjavato, South-Eastern Madagascar. We aim to determine how the land use types influence the occupancy of M. jollyae over a landscape highly modified by humans that includes forest fragments, agricultural land, and reforestation areas. We set Sherman traps along 69 transects (300m in length) over an area of 47.3km² from April 2018-July 2019 for capture-mark-recapture sampling. Each transect was repeated 5 times over a two week period, with up to 6 transects sampled simultaneously. We created a land use land cover map with Sentinel 2 imagery to determine the land use categories around each transect (forest, reforestation, and agricultural land).

Results/Conclusions

We had a total of 4,615 trap nights where we captured 55 individual M. jollyae over the 69 transects, with 5 individuals also recaptured on occasion. The naïve occupancy (with no modelling of detection) for M. jollyae over the whole landscape is 0.25. They were found on 29.4% of forest transects, 25% of agricultural land transects, and 20% of reforestation transects. Similar to other species of mouse lemurs, M. jollyae use a variety of vegetation types, indicating that they can survive outside of the forest. It is a promising sign for their persistence that they are starting to inhabit the newly created reforestation areas, first established in 2012. This underscores the importance of land use categories managed with local communities, for the conservation of this highly range-restricted primate.