Abstract
The Alaotran gentle lemur Hapalemur alaotrensis is a Critically Endangered lemur, which exclusively inhabits the marshes around Lac Alaotra in northeast Madagascar. In the past decades the population of H. alaotrensis has experienced a dramatic decline due to poaching, habitat destruction and degradation. Surveys have been carried out periodically to follow the status of the population. Here we present the results of a survey carried out between May and June 2008 in the southwestern part of the marshes around Alaotra and discuss the key findings derived from the analysis of the data collected. Our study indicates that the probability of detecting the species in an area where it is present is very low and depends on factors that vary in space and time. These results stress the need to account for imperfect detection when monitoring this species, an issue especially relevant when reporting population trends. Our analyses also show that habitat fragmentation is a key determinant of habitat suitability for H. alaotrensis, with fragmented areas of marsh showing low suitability. Finally, our observations and analysis suggest that the protection provided by the local community to H. alaotrensis in Andreba is contributing to the conservation of this Critically Endangered species. This highlights the need to continue working on engaging the local communities in the conservation of the marshes at Lac Alaotra as a critical element to secure the future of H. alaotrensis. KEYWORDS: bandro, habitat suitability, habitat fragmentation, imperfect detection, Maxent.
Highlights
IntroductionWith around 20,000 ha of open water area, Lac Alaotra is Madagascar’s largest lake and constitutes one of the main inland fisheries in the country
The Alaotran gentle lemur Hapalemur alaotrensis (Rumpler 1975), initially regarded as a subspecies of the lesser gentle lemur Hapalemur griseus but currently considered a IDepartment of Life Sciences, Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire, SL5 7PY, UK.II National Centre for Statistical Ecology, School of Mathematics, Statistics and Actuarial Science, University of Kent, Canterbury, Kent, CT2 7NZ, UK.III Durrell Wildlife Conservation Trust, Les Augrés Manor, Trinity, Jersey, JE3 5BP, Channel Islands.IV Department of Biology & Biochemistry, University of Bath, Bath, BA2 7AY, UK.separate species (Groves 2005), only occurs in the marshes around Lac Alaotra, in the Alaotra - Mangoro Region, northeast Madagascar
H. alaotrensis encounters were relatively frequent in some areas while no groups were found in others, which suggests that the presence of the species or the probability of detection, or both, depend on characteristics of the sites surveyed
Summary
With around 20,000 ha of open water area, Lac Alaotra is Madagascar’s largest lake and constitutes one of the main inland fisheries in the country. The lake is surrounded by a vast wetland consisting of marshes and rice fields and is considered an important biodiversity area (Pidgeon 1996). The Alaotran basin produces a large proportion of the national rice harvest (Pidgeon 1996) and is popularly known as ‘the granary of Madagascar’. The NAP set out a num ber of management zones for the marsh and open water, includ ing no - fishing zones, areas for strict biodiversity conservation, and areas of regulated fishing and reed extraction, no formal management authority exists yet to ensure compliance
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
