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Antananarivo, Madagascar

Ralisata M.,Madagasikara Voakajy | Ralisata M.,University of Antananarivo | Rakotondravony D.,University of Antananarivo | Racey P.A.,University of Exeter
Acta Chiropterologica | Year: 2015

Here we expand our previous study to provide more detailed information on the relationship between the male eastern sucker-footed bat Myzopoda aurita and the traveler's tree Ravenala madagascariensis in south-eastern Madagascar, during six month-long field work sessions carried out over two years. We caught 593 bats, 229 newly caught and 364 recaptures, exclusively males, roosting in 37 day roosts in the partially unfurled central leaves of R. madagascariensis. No bats were found in any other roosting situation. To analyse potential roost availability, we monitored partially unfurled central leaves on R. madagascarienis on four transects and 12% appeared suitable as M. aurita roosts. These leaves took three to 25 days to unfurl, and roosts became available between one and 19 days after unfurling commenced. Day roosts were occupied for one to 12 days. Bats were more likely to occupy roosts in taller trees. The size of roosting groups varied between one and 36 individuals. Movements of bats between roosts were recorded on 35 occasions and between two and nine individuals of M. aurita found in one roost were subsequently found together in a different roost. Myzopoda aurita occurs in degraded forests and anthropogenic habitats of eastern Madagascar where it may be affected by loss of roosts since R. madagascariensis is used extensively for building and thatching houses. © Museum and Institute of Zoology PAS. Source

Andrlanaivoarivelo A.R.,CNRS Ecosystems, Biodiversity, and Evolution Laboratory | Petit E.J.,CNRS Ecosystems, Biodiversity, and Evolution Laboratory | Razafindrakoto N.,Madagasikara Voakajy | Racey P.A.,University of Exeter
Revue d'Ecologie (La Terre et la Vie) | Year: 2012

Experiments in a flight cage and observations in the field were carried out in North-western Madagascar to study the feeding preference of Rousettus madagascariensis (Family Pteropodidae) between an introduced fruit, jujube (Ziziphus jujuba, Family Rhamnaceae) and an endemic fig (Ficus sakalavarum, Family Moraceae) during the dry season, in May and June 2009. We also investigated quantitative aspects of seed dispersion by R. madagascariensis. Juvenile bats (13) fed intensively on F. sakalavarum, while adults (20) ate both fruit species but with a pronounced preference for unripe Z. jujube fruits. This preference for unripe (immature) fruit, the seeds of which are too large to swallow, suggested that R. madagascariensis does not affect seed dispersal in Z. jujuba. Almost half of the ingested seeds of F. sakalavarum were found in faeces of R. madagascariensis voided during the night in the flight cage, and the remainder was found in regurgitated 'ejecta' pellets. Rousettus madagascariensis is thought to be an effective seed disperser off; sakalavarum, particularly for isolated trees or those in forest fragments where other frugivores are rare. Source

Keane A.,Bangor University | Keane A.,University College London | Keane A.,UK Institute of Zoology | Hobinjatovo T.,Madagasikara Voakajy | And 4 more authors.
Animal Conservation | Year: 2012

Primates are a global conservation priority, with half of known species considered threatened with extinction. Monitoring trends in primate populations is important for identifying species in particular need of conservation action, and evaluating the effectiveness of interventions. Most existing primate survey methods aim to measure abundance. However, obtaining estimates of abundance with acceptable precision to detect changes in population is often expensive and time consuming. Evidence from other taxa suggests that estimating occupancy (the proportion of the area used by the species) may be less resource-intensive, yet still provide useful information for monitoring population trends. We investigate the potential of occupancy modelling for monitoring forest primates using a case study of three species of diurnal lemurs in the eastern rainforest of Madagascar. We estimated detectability and occupancy from a survey with three visits to 30 sites. Our estimates suggest that precision in occupancy estimates would be maximized by visiting a larger number of sites (therefore with limited repeat visits) for Indri indri, whereas the optimal monitoring design for Eulemur fulvus and Propithecus diadema, which showed very low detectability in our surveys, involves more frequent visits to fewer sites. Power analyses suggested that a meaningful reduction in occupancy could be detected with reasonable effort for easily detected species, but the method may prove impractical for more cryptic species. Primates pose a number of practical challenges for occupancy modelling, including choosing appropriate survey designs to satisfy closure assumptions. We suggest that if these issues can be overcome, occupancy modelling has the potential to become a valuable addition to the monitoring toolbox for the study of forest primates. © 2012 The Zoological Society of London. Source

Randrianantoandro C.,Madagasikara Voakajy | Razafimahatratra B.,University of Antananarivo | Soazandry M.,University of Antananarivo | Ratsimbazafy J.,University of Antananarivo | And 3 more authors.
Amphibia Reptilia | Year: 2010

Information on the distribution and abundance of chameleons in Madagascar is required to develop conservation plans that integrate protected area management and sustainable use. We surveyed chameleons in eight sites in deciduous forest in Menabe, western Madagascar. Brookesia brygooi was the most frequently detected species, with a population density of 35 ha -1. Furcifer species were less common, with calculated densities of 7.2 ha -1 (F. labordi), 3.0 ha -1 (Furcifer sp.) and 1.3 ha -1 (F. oustaleti). Chameleon abundance varied according to altitude (B. brygooi) and no clear effect from logging was detected (all species). A lack of information on chameleon diurnal habitat requirements impedes a fuller assessment of the extent to which these species are tolerant to forest degradation. There were interspecific differences in the height of nocturnal perches and additional studies are needed to determine whether these are related to diurnal resource partitioning. Furcifer labordi and Furcifer sp. are of conservation concern because they are restricted to native forests in western Madagascar. © Koninklijke Brill NV, Leiden, 2010. Source

Ralisata M.,Madagasikara Voakajy | Andriamboavonjy F.R.,University of Antananarivo | Rakotondravony D.,University of Antananarivo | Ravoahangimalala O.R.,University of Antananarivo | And 2 more authors.
Journal of Zoology | Year: 2010

We studied the social organization, use of foraging habitat, roost switching and diet of the sucker-footed bat Myzopoda aurita in south-eastern Madagascar. All 138 bats caught were males, 18 of which were selected for radio-tracking. The areas individual bats used for foraging varied between 7 and 108 ha (100% minimum convex polygon). Bats foraged close the roost for the first hour after emergence, then travelled up to 1.8 km away. Compositional analysis revealed that they selected coffee plantations, degraded humid forest and wooded grassland more than any other habitats. All 133 roosts located consisted of the partially unfurled leaves of Ravenala madagascariensis and housed between nine and 51 individuals. Bats changed roosts every 1-5 days. Their diet comprised mainly of Lepidoptera and Coleoptera. No ectoparasites were observed. Myzopoda aurita is one of the few mammals endemic to Madagascar that uses disturbed patches of vegetation and is not therefore threatened by deforestation, although it may be affected by loss of roosts for building materials. The search for females continues. © 2010 The Authors. Journal compilation © 2010 The Zoological Society of London. Source

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