BackgroundAn understanding of the conservation status of Madagascar's endemic reptile species is needed to underpin conservation planning and priority setting in this global biodiversity hotspot, and to complement existing information on the island's mammals, birds and amphibians. We report here on the first systematic assessment of the extinction risk of endemic and native non-marine Malagasy snakes, lizards, turtles and tortoises.Methodology/Principal FindingsSpecies range maps from The IUCN Red List of Threatened Species were analysed to determine patterns in the distribution of threatened reptile species. These data, in addition to information on threats, were used to identify priority areas and actions for conservation. Thirty-nine percent of the data-sufficient Malagasy reptiles in our analyses are threatened with extinction. Areas in the north, west and south-east were identified as having more threatened species than expected and are therefore conservation priorities. Habitat degradation caused by wood harvesting and non-timber crops was the most pervasive threat. The direct removal of reptiles for international trade and human consumption threatened relatively few species, but were the primary threats for tortoises. Nine threatened reptile species are endemic to recently created protected areas.Conclusions/SignificanceWith a few alarming exceptions, the threatened endemic reptiles of Madagascar occur within the national network of protected areas, including some taxa that are only found in new protected areas. Threats to these species, however, operate inside and outside protected area boundaries. This analysis has identified priority sites for reptile conservation and completes the conservation assessment of terrestrial vertebrates in Madagascar which will facilitate conservation planning, monitoring and wise-decision making. In sharp contrast with the amphibians, there is significant reptile diversity and regional endemism in the southern and western regions of Madagascar and this study highlights the importance of these arid regions to conserving the island's biodiversity.
The morphometry, age structure, and abundance of the panther chameleon Furcifer pardalis (Cuvier 1829) were studied at Nosy Be (NW Madagascar). Males were larger and heavier than females (SVL, 138.38 ± 35.94 vs 91.92 ± 18.48 mm; mass, 61.06 ± 39.86 vs 22.62 ± 13.17 g). The age, assessed by skeletochronology, was usually less than one year, with a maximum of 2 years. The density estimate for adult individuals was higher along roads (42.21/ha) than in agricultural habitats far from roads (17.43/ha). Compared to other species of Malagasy chameleons, F. pardalis is infrequent in pristine and close forests, while, like other Furcifer species, it is more closely associated with riverine habitats. The higher concentration of individuals in forest-like bands along roads is explained by the presence of a suitable vegetation band along roads and the similarity of this habitat to the riverine and ecotonal forests preferred by chameleons of the genus Furcifer. The life history traits, high fecundity and short life span indicate that the current collecting rate does not affect the abundance of F. pardalis. Measures of chameleon conservation at Nosy Be should consider the preservation of the anthropogenic forest band.
During a zoological survey in north-west Madagascar (Sahamalaza Peninsula) we documented aspects of the natural history of Boophis occidentalis (formerly a subspecies of B. albilabris and here raised to species level). Individual age assessed by skeletochronology ranged from 4 to 11 years. Breeding behaviour was observed at a seasonal stream after heavy rainfalls: ®ve choruses of eight to 90 males aggregated in shallow brook sections. The males emitted low frequency calls and engaged in scramble battles. Only two females were found. A couple laid a large number of eggs, attached as a single layer on submerged stones. Tadpoles reared from these eggs had the typical morphology of brook-breeding Boophis species with a 1:5+5/3 keratodont formula and a relatively¯attened body. Adult males had an anteroventrally oriented cloaca, a morphological trait shared with B. albilabris. Advertisement calls were similar in general structure to those of B. albilabris recorded at Anjanaharibe-Sud. They were unharmonious and consisted of pulsed notes emitted at irregular intervals. Much lower pulse rates in B. albilabris (30±38 pulses/s) than in B. occidentalis (90±109 pulses/s) support the speci®c distinctness of these taxa. The combination of characters related to reproductive biology in B. occidentalis and B. albilabris is unique in Boophis. The acontinuous breeding behaviour and large number of eggs per clutch are traits found in the pond-breeding species of the B. tephraeomystax group, while larval morphology and habitat are characteristic of brook-breeding species. Available morphological and molecular data place B. albilabris and B. occidentalis into the brookbreeding Boophis radiation. The acontinuous timing of reproduction and large egg number may be secondary adaptations that allowed the species to colonize arid regions of western Madagascar.
Amphibians and reptiles were surveyed at Berara, a forest on the Sahamalaza Peninsula, NW Madagascar. Visual methods and pitfalls were used, leading to the discovery of 12 amphibian and 30 reptile species. The herpetofaunal community appeared as a mosaic of dry forest species and species from the more humid Sambirano Domain. The comparatively low amphibian diversity may be correlated with the ecological characteristics of Berara, in particular with the scarcity of permanent water bodies and strong seasonality. The survey provided new records of Aglyptodactylus securifer and Heterixalus luteostriatus, further north than hitherto known. The encountered specimens of the treefrog Boophis albilabris displayed characters typical for the subspecies occidentalis, resulting in a substantial range extension. Boophis jaegeri proved to be abundant at Berara, which is the second known locality for this treefrog. The reptile fauna included taxa of special interest, such as a new Pseudoacontias burrowing skink, a new Amphiglossus, the aquatic skink Amphiglossus reticulatus, and many geckos. Presence of several taxa known only from restricted western localities (e.g., Aglyptodactylus securifer, Amphiglossus reticulatus) or from a few protected areas (e.g., B. jaegeri), as well as of several regional endemics emphasises the importance for conservation of the Sahamalaza transitional forest, which should urgently be included in the network of protected areas in Madagascar.
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