Lemurs and Men
Chloe Chen-Kraus knows her subjects by face—and found that an endangered species just thrive in disturbed, human-used, landscapes.
To begin her doctoral research, Chloe Chen-Kraus drew the faces of lemurs in a notebook. Chloe spent this past field season following lemurs through the forests—and forest edges—of southwestern Madagascar. Research on the Verreaux’s sifaka, Chloe’s study subject, has been limited to strictly protected forests and scientists don’t know if forest edges, areas used heavily by humans, can host the endangered species. In tracking the primate communities, she pushed traditional lemur studies beyond areas already reserved for conservation. Chloe explored the relationship between community land use and the ecology of this endangered species.
Madagascar is famous for its biodiversity—including its lemurs. However, human activities have directly contributed to the dramatic decline of some of these species. “The biggest threat to lemurs where I work is the grazing of livestock. The villagers will graze their livestock in the forest to protect them from what they call cattle rustlers.” Grazing reduces the forest cover, as do herders cutting tree branches for fodder. Both reduce undisturbed forest habitat and, consequently, conservation on the island has tried to protect large swathes of preserved woods for lemur use. Chloe wanted to know how land beyond these reserves can also be managed for the species.
In many ways, Chloe came into an ideal study site. Her research is made possible by the resident research team at Bezà Mahafaly Special Reserve, in the southwest of Madagascar. “I’m working at a small 4,200 hectare reserve of protected forest. It’s a really interesting setup for my research project because the reserve has recently been expanded to include new core protected areas,
as well as sustainable use zones,” she said. “There are now zones with management regulations that map onto different disturbance classes. I have this perfect setup to look at how different degrees of human activity affect the forest and the lemurs.” She has the opportunity to work in sifaka habitat areas that have been disturbed—and to quantify the effects of humans in these mixed-use regions.
Tracking lemur use of these areas required Chloe to learn more than the animal’s natural history. She started with the species’ call, learning to make the sound herself walking transects through the forest with the Beza research team. “Every fifty meters we made a lost call, the sifaka lost call. The sifakas are white and while you can sometimes see them easily, they’re very quiet and kind of inconspicuous. If you make these calls, they’ll respond. When we hear a group, we go find where these animals are.” They mapped the locations of the lemurs across their landscape, estimating the number and placement of the animals, and tracked the movements of specific family groups.
The call itself, Chloe said, sounds “kind of like an owl, but it’s a contact call between the group. If one’s strayed off foraging it will make that call. The group will either respond with that same call, or the sifaka call, which is how they get their names, which is a really throaty ‘si-FAK,’ ‘si-FAK.’”
Chloe also needed to learn individual traits. To effectively track these family groups, she needed to know each animal. “I drew pictures of all of their faces. Some of them have different colored eyes. They have a brown cap and then white around their faces and the pattern of the outline of the cap was sometimes distinctive, so I had drawings in my notebook that I made trying to look at these features.” By knowing which animals are where, Chloe could follow their behavior, recording how long they feed and rest, how often they are interrupted, in order to investigate how human activities affect them.
And Chloe found that this species might actually survive, and potentially thrive, within the matrix of disturbance. “My hope is that if we really understand what human activities negatively impact the lemurs then we will be able to better manage these areas to sustain not only the wildlife populations but also the human communities.”
“I was so shocked to find lemurs in all of these habitats, even though there are humans cutting trees and grazing livestock and they seem like pretty disturbed areas to me. But the lemurs are there and they’re reproducing. I might find that they are not nearly as impacted as we think. As long as there is a certain amount of forest cover, and they have some good food resources, they might not be as impacted as we thought.”
Her research also has implications for community relations. How can you build conservation areas that support local communities? The reserve, she said, tries “to take into consideration the needs and wants of the community in their planning process. I think this new zonation will be a really interesting test of how that plays out. Are community members satisfied with the expansion of protected areas?” Is it possible for communities of this endangered species to thrive in areas shared with local human ones?
However, there is not only a close relationship between species and habitat, but also species and funding. That funding is supposed to protect the species by protecting their lands. “A lot of conservation work in protected areas of Madagascar are either focused on protecting forested landscapes or protecting the charismatic species.” It’s how the area gets a lot of international funding, she added. Learning more about the species has direct implications for funding. Chloe will continue to receive field data from the research team at Beza and will return to Madagascar to continue her field work in June. She intends to expand the study to a landscape-scale analysis of sifaka distribution and genetics.
“My work at Beza will provide a benchmark for a landscape-scale study of human land use impacts on Sifakas. No one’s really working with the lemurs outside of the protected areas in this region. I think that’s very important because the protected areas only cover a small fraction of the important habitat.” Academically, Chloe’s work falls into a meeting-place of conservation biology, ecology, and anthropology. In practice, it combines endangered species conservation and rural economics—as well as sifaka mimicry.
Edited by Juliana Hanle