July 6, 2013
Sportive Lemurs Avoid Danger By Listening To Their Neighbors
April Flowers for redOrbit.com - Your Universe Online
The Madagascan Sahamalaza sportive lemur (Lepilemur sahamalazensis) is an endangered species that scientists know very little about. A new study, led by the University of Bristol reveals that the sportive lemur uses the alarm calls of birds and other lemurs to warn it of the presence of predators, the first time this behavior has been observed in a nocturnal and solitary lemur species.
Prior to this study, scientists knew that the sportive lemur was vulnerable to both air and ground predators because of its habit of roosting during the day in open situations, such as tree holes. Virtually nothing else was known, as this species is not kept in any zoo, despite being classified as Critically Endangered on the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species in 2012.
Dr Melanie Seiler, a researcher at Bristol Zoo and the University of Bristol, said: "We were seeking any information we could gather that could help us understand this species better, with the objective of improving targeted conservation efforts."
"One of the problems of small nocturnal species is that they don't get a great deal of scientific or conservation attention. The Sahamalaza sportive lemur doesn't have striking blue eyes like blue-eyed black lemurs or any other unusual features. That means that no-one had really looked into what these animals need to survive."
The team, which included researchers from Bristol Zoo and the University of Torino, wanted to increase our knowledge of this small animal to help conservation efforts. The findings of their study were published in PLOS ONE. The lemur populations of Sahamalaza National Park in Madagascar are threatened by hunting, forest fragmentation and deforestation. The remaining 200 hectares of fragmented forest is vitally important for the continued survival of this and other lemur species.
Dr Marc Holderied of the University of Bristol said, "Until our study, a solitary and nocturnal lemur species had never been tested to see if it could understand other species' alarm calls and differentiate between them. We were also the first to test any species of lemur to see if it could recognize the alarm calls of a non-primate species."
The research team found that sportive lemurs increased their vigilance significantly after hearing playbacks of the alarm calls of the crested coua and the Madagascar magpie-robin. The aerial alarm calls of the blue-eyed lemur also caused an increased vigilance, with the sportive lemurs scanning the sky but never the ground. This suggests they classified the alarm call correctly.
Dr Holderied said, "Our results indicate that the Sahamalaza sportive lemur is capable of gleaning information on predator presence and predator type from the referential signals of different surrounding species. Examples for cross-species semantics in lemurs are rare, and this is the first record of lemurs using information across vertebrate classes."