The cloudforests of the Ranomafana National Park in Eastern Madagascar are pitch black, and the warm drizzle is slowly soaking us. But evolutionary biologist Tuomas Aivelo from Helsinki University and his colleagues Herman Rafalinirina and Victor Rasendry stride boldly up a steep, narrow path.
These unspoilt natural forests lie in a uniquely diverse area whose forest habitats are being mapped as part of FANC’s Manondroala Project.
Every few minutes one of the researchers suddenly charges off the path into the undergrowth to fetch a metal box trap. Aivelo’s team are trapping tiny brown mouse lemurs to study their health and parasite infestation. “Mouse lemurs are the world’s smallest primates. By catching and studying them repeatedly we can assess how parasites affect their health over their lifespan,” he explains.
This work could have implications for human medicine, since as primates we must cope with similar health problems to those facing lemurs – including nasty diseases that could jump between human and primate populations.
We find seven mouse lemurs in the traps this evening. The scientists carefully carry them up to a shelter high up on a hill in the forest, where there is a sturdy table suitable for surgical examinations of the tiny primates. Tuomas, Herman and Victor measure and weigh them, take their temperatures anally (this looks very painful!), and collect fecal samples for parasite analysis. One mouse lemur caught for the first time has a microchips implanted in his neck for future identification.
Though the whole process looks extremely traumatic, the mouse lemurs never seem to learn to avoid the banana-baited traps. One individual named Napoleon has been trapped more than 150 times.
As we examine our catch, another mouse lemur approaches through the forest canopy to watch over the operation. His eyes glow bright in the light of our torches, but he is not scared off. Perhaps one of the patients is his mate.
During his field research Tuomas is based at Centre ValBio in Ranomafana. Helsinki University is one of the main founders and funders of this newly expanded research station. Many Finnish researchers have come here to study creatures ranging from rare bamboo lemurs to colourful dung beetles. Student groups from Helsinki also visit the centre annually.
I feel privileged to have accompanied these expert biologists on their groundbreaking fieldwork in some of the last natural forests in this unique hotspot for global biodiversity.
“This is a great location in one of the few accessible primary rainforests left in Madagascar, with many lemurs and a long history of research,” says Aivelo. “For evolutionary biologists like me Madagascar is an intriguing island full of mysteries!”
– Fran Weaver
Read more thoughts by Fran Weaver, freelance journalist who visited Madagascar with Project Manondroala in October-November 2012, from the earlier post in this blog “Mad about Madagascar“.