Madagascar’s forests have been subject to tragic deforestation in recent decades, and much of the remaining forest exists in isolated forest fragments. In the highlands of Madagascar, on the island’s central plateau, it is hotly debated how much land was once covered in forest, with increasing evidence that grasslands are indeed native and historic. However, it is in living memory that much of the riparian valley forests have been deforested. My PhD at Cardiff University, in collaboration with Durrell Wildlife Conservation Trust, aims to study how amphibian’s genetics are affected by this habitat fragmentation.
While mapping my field sites on qGIS, I identified two habitat fragments north of my main field site, Ambohitantely, called Ankafobe. This reserve is managed by the Missouri Botanical Garden, in collaboration with the local led VOI Sohisika and is one of Madagascar’s smallest protected areas covering 133 hectares. However just 27 ha of forest remains in the reserve and they are vulnerable to man-made fires which are carried across the landscape by wind. I knew these fragments would be interesting sites to add to my fragmentation study, given their small size and isolation. Further, no one had ever surveyed frogs here before, so the managers had no idea what species they had. This would be an exciting opportunity for any herpetologist!
So off we went to do a rapid amphibian assessment in March 2020. We conducted buccal swabbing for DNA barcoding of all the species present, given the high level of both cryptic and candidate species in Madagascar. Our most surprising and exciting find was the Critically Endangered EDGE species Anilany helenae. This species was previously thought to be a microendemic to Ambohitantely Special Reserve, 10km south east of Ankafobe. This finding extends the species’ range to another protected area and helps safeguard the species. It makes you wonder what other un-surveyed, and unprotected, remnant fragments across the central plateau may be home to this tiny (SVL 10-15mm) species. We also found an Endangered species Boophis andrangoloaka, which extends this species’ range to a third known protected area. We found a total of 14 species in the reserve (Mullin et al 2021).
As deforestation continues across the country, these findings highlight the importance of small forest fragments for the conservation of Madagascar’s biodiversity. These fragments must be protected to avoid the loss of these unique species and further inventories are required of remnant forests which are currently unprotected and often logged and burned for charcoal. The protection efforts ongoing at Ankafobe are inspiring, and it hopes to gain official government protected status soon. While our inventory is likely an underestimate of the frog species present, we hope that our results will support this reserve in their ongoing conservation efforts. This study also highlights the efficiency of non-invasive buccal swab sampling for inventory type studies, without the need to collect specimens in degraded habitats.
Watch this space for our large-scale habitat fragmentation study in which the data from Ankafobe is included.
By: Katherine Mullin. Cardiff University, Durrell Wildlife Conservation Trust
Photo: Katherine Mullin and Manoa G. Rakotomanga