194 research outputs found

    Does selective wood exploitation affect amphibian diversity? The case of An'Ala, a tropical rainforest in eastern Madagascar

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    The diversity of amphibians before and after low-level forest exploitation in An'Ala forest in central-eastern Madagascar was compared over the course of 4 years. Neither abundance nor diversity of amphibians generally were significantly affected by low-level selective logging, although the abundance of individual species differed. Mantelline anurans were the most sensitive, in contrast to the tree frogs of the subfamily Boophinae (Mantellidae) and Cophylinae (Microhylidae). The abundance of Mantellinae anurans decreased by 15.8% after logging, whereas Boophinae and Microhylidae anurans increased by 12.1% and 3.7%, respectively. In general, species strongly tied to rainforest habitat showed a non-significant 10.1% decrease in abundance after logging. It appears therefore that amphibians are relatively resilient to a low-level of forest exploitation and their diversity is apparently not affected, at least in the short-term. This and other studies have, however, shown that logging commonly results in a shift in species composition, with species typical of pristine rainforests being replaced by species adapted to secondary habitats

    Valorisation of Madagascar’s wildlife trade and wildlife tourism; what are the conservation benefits?

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    Wildlife tourism and wildlife trade may appear juxtaposed, but are two, potentially aligning, income generators that could benefit conservation in developing countries. Utilising data sets collated from Madagascar’s Ministère du Tourisme and CITES respectively for the period 2007 to 2018, this study estimated levels of income from wildlife tourism and wildlife trade for Madagascar. Between 2007-2018, tourism reported yearly incomes ranging from a low of US 1.4millionuptoahighofUS1.4 million up to a high of US 15.7 million. However, it was unclear what percentage of this figure flowed to benefit local communities. Alternatively, using reported networks for the live wildlife trade, the estimated economic value reaching collectors and/or intermediaries on Madagascar was US $72,299.80 for the period 2007 to 2018. Both revenue generators operated within different geographical areas, with tourism opportunities presenting themselves to communities adjacent NPs, while wildlife trade networks were not restricted to NPs and operated sporadically across Madagascar. Hence, the economic benefits reached different Malagasy participants across the country. The management of both activities needs great care to ensure that environmental impacts and sustainability are core measures on any such activities. Whilst this study shines light on economic values and novel perspectives regarding these two trade types, it also highlighted knowledge gaps. Thus, indicating where much greater research attentions was required to allow better understanding of the specific benefits and risks from engaging with both trade types for local Malagasy people and their environments

    Are there shared general patterns of specific diversity, abundance, and guild structure in snake communities of tropical forests of Madagascar and continental Africa?

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    A comparative study of snake community composition of 45 tropical forest patches, including both original and literature data, is presented. Twelve study areas are situated in Nigeria, one in Cameroon, and 30 in Madagascar. Two forest sites from Panama were also used as outgroups. There was a remarkable consistency among sites in inter-regional comparisons in terms of mean number of species observed x min.-1 . The highest similarities were between Nigerian and Malagasy sites and between Cameroon and Nigerian sites, whereas similarities between ail these African sites and Panama sites were lower. Altitude and linear distances among sites did not influence significantly the snake species detection and abundance. Nigerian sites had comparatively higher numbers of semi-aquatic taxa than Malagasy sites. The terrestrial guild was the dominant one, and the arboreal guild was constituted by a remarkable diversity of species, in nearly ali sites of both Nigeria and Madagascar. There was a very low diversity of syntopic fossorial species in both Nigeria and Madagascar (in ali 22 study plots, only 1 or 2 fossorial species were found). In Nigerian sites there was a general prevalence of primarily lacertophagous and mammalophagous species, but batracophagous and ornithophagous species were also quite abundant. In the Malagasy sites lacertophagous species were significantly prevalent, followed by batracophagous species, whereas species with other dietary preferences (e.g., mammalophagous) were much under-represented. The abundance of species feeding on invertebrates and of generalist species was sirnilar in the two geographie regions, whereas piscivorous species were found only in the Nigerian sites. The scarcity of mammalophagous, piscivorous and ornithophagous species in Madagascar could be interpreted as a general biogeographie pattern in terms of food type availability (taking into account the scarcity of some types of prey in Malagasy forests and freshwater streams) as weil as in terms of snake size distributions. With regard to snake body size distributions in the various examined communities, it appeared that forest environments of both Nigeria and Madagascar can house a similar snake community as for numbers of species < 2 m in length, but Nigerian environments can harbour numbers of giant and very large species (from 2 to 9 m in length) that cannot be hold in Malagasy forests. The ecological patterns emerged in this comparative study are discussed in the light of current community ecology theory and biogeographyUne étude comparative de la composition des communautés de serpents de 45 sites forestiers tropicaux est présentée, appuyée sur des données originales ou prises dans la littérature. Douze sites sont localisés au Nigéria, un au Cameroun et 30 à Madagascar. Deux sites forestiers de Panama sont également utilisés dans les comparaisons. Les comparaisons inter-régionales montrent une remarquable constance entre les sites du nombre moyen d'espèces observées par minute ; les plus fortes similitudes s'observent entre les sites nigérians et malgaches ainsi qu'entre les sites nigérians et camerounais ; en revanche, les similitudes sont plus faibles entre tous ces sites africains et malgaches et les panaméens. L'altitude et la distance entre sites n'influent pas de manière significative sur la détection et l'estimation de l'abondance des espèces. Les sites nigérians présentent davantage de taxa semi-aquatiques que les malgaches. Au Nigéria comme à Madagascar, la guilde des terrestres est dominante et la guilde des arboricoles constituée d'une remarquable diversité d'espèces. La diversité des espèces fouisseuses syntopiques est très faible tant au Nigéria qu'à Madagascar (1 à 2 espèces seulement dans chacun des 22 sites étudiés). Sur les sites nigérians on observe en général une dominance des espèces spécialisées dans la consommation de lézards et de mammifères, mais les batracophages et les ornithophages sont eux aussi abondants. Sur les sites malgaches, on observe une prévalence significative des consommateurs de lézards, suivis par les chasseurs de batraciens, les autres spécialistes (p.e. les prédateurs de mammifères) étant bien moins représentés. Les abondances des espèces généralistes et des espèces se nourrissant d'invertébrés sont semblables dans les deux régions géographiques alors que les piscivores n'ont été rencontrés qu'au Nigéria. La rareté à Madagascar des espèces consommatrices de mammifères, de poissons et d'oiseaux pourrait s'interpréter comme un patron biogéographique général en termes de disponibilité des types de proies (en considérant la rareté relative de certains types de proies dans les forêts et rivières malgaches) ainsi que de distribution des tailles des serpents. Pour ce qui concerne cette distribution de la taille des serpents au sein des divers peuplements étudiés, il apparaît que le milieu forestier peut héberger autant d'espèces de moins de 2 m de long au Nigéria qu'à Madagascar mais que seul le Nigéria héberge des espèces géantes ou du moins de très grande taille (de 2 à 9 m de long). Les patrons écologiques qui émergent de cette étude comparative sont discutés dans le cadre des théories actuelles de l'écologie des peuplements et de la biogéographie

    Malagasy amphibian wildlife trade revisited: improving management knowledge of the trade

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    Madagascar is a biodiversity hotspot with a long history of trading in its wildlife, especially its hyper diverse Amphibian taxa. Due to globally raised concerns over the conservation for harvested amphibian species on Madagascar, CITES was introduced as a global mechanism to monitor and regulate the trade. Utilising data collated from the CITES Trade database, this study sought to investigate the trade and CITES effectiveness in managing the trade. Over the 28 year period investigated, 20 known amphibian species were exported from Madagascar with a total of nearly 271,000 individuals. Formal descriptions of Malagasy amphibian species has and continues to increase greatly over time, there has not been a concomitant, longitudinal relationship in the numbers of individuals traded. Overall, the numbers of individuals traded has declined over time but, where assessments were provided by the IUCN Redlist, population declines were reported in all but one species of Malagasy amphibian. Mantella (97.5%) continue to dominate the trade with certain, high conservation concern species continuing in the trade. Despite early concerns over the effectiveness of CITES actions, after concerted efforts it appears that CITES actions were having an impact in regulating the trade. However, going forward, concerns remain over the appropriateness of the quotas set and the robustness of their underpinning NDFs. Furthermore, with the increase in recognised species raises the potential for incorrect species labelling on CITES permits that needs attention

    A new finding of Salamandra lanzai in the Upper Sangone Valley (NW Italy) marks the species' most disjunct population (Amphibia: Urodela: Salamandridae)

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    The presence of Salamandra lanzai was confirmed for the Upper Sangone Valley (Turin Province, NW Italy), within the Parco Naturale Orsiera Rocciavré. The species attribution was further supported by morphological and genetic (16S) analysis and represents the north-eastern most limit of the species’ distribution. This salamander was so far known only for a few major alpine valleys of Italy (Po, Pellice, and Germanasca Valleys), and France (Guil Valley). The new finding is especially interesting since it is separated from its closest known locality by about 15 km. For such a reason this population needs to be carefully managed

    Spatial Ecology of an Arboreal Iguana (Oplurus cyclurus) in a Treeless Landscape

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    Understanding the spatial ecology of species has important implications for conservation, as it helps identify suitable habitats and minimum requirements for biodiversity monitoring and management. The spiny-tailed lizard Oplurus cyclurus is a widespread endemic iguanid occurring in dry areas of southern and western Madagascar. While the species is known to be mostly arboreal, populations of the Isalo sandstone massif suggest local adaptation to a less forested savannah and a more exposed habitat. We radio-tracked 19 spiny-tailed lizards to investigate the species’ rock-dwelling behaviour and spatial ecology at Isalo National Park. Tracked individuals showed high site and burrow fidelity, and a basking behaviour mostly tied to the accessibility of their burrow, the time of day, and their life stage. Activity peaked during the sunniest hours, while juveniles were more active than adults with unfavourable weather conditions. Despite high burrow fidelity, lizards used shelters non-exclusively, regularly changing (approx. once a week) with neighbouring burrows (average distance between burrows = 13.6 m). However, there was no obvious relation between lizards’ body and/or tail size and the width and depth of selected burrows. Dynamic Brownian Bridge Movement Models estimated frequented areas over 247.8 m2 (95% isopleth), where territorial overlap is common. Our results challenge the notion that burrow-site fidelity is the sole driving factor behind space utilization in the studied population. We argue that the apparently unusual saxicolous habits imposed by habitat features (the absence of trees) may lead to local behavioural adjustments influencing antipredatory and foraging strategies, as well as intraspecific interactions.info:eu-repo/semantics/publishedVersio

    Two new species of terrestrial microhylid frogs (Microhylidae: Cophylinae: Rhombophryne) from northeastern Madagascar

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    We describe two new microhylid frog species of the genus Rhombophryne from the humid forests of northeastern Madagascar: Rhombophryne botabota sp. n. and R. savaka sp. n. e former is a medium-sized species, characterised by darkened lateral sides of the head (present in only one other congener, R. laevipes) and a unique combination of morphological, osteological, and molecular characters. e latter is a rather small species, characterised by medially undivided vomerine teeth with two large lateral diastemata, and presence of inguinal spots. Rhombophryne savaka sp. n. is the first species of the genus known from Makira Natural Park, and is reported also from Marojejy National Park and Ambolokopatrika (Betaolana Forest). Although its distribution range is relatively large compared to those of congeners, its known extent of occurrence is less than 2,000 km2. As deforestation and habitat degradation persist as threats despite formal legal protection, we suggest an IUCN Red List status of Vulnerable for this species. Rhombophryne savaka sp. n. is possibly endemic to the Marojejy National Park, like several other Rhombophryne species, but is unusual in being found at a relatively low altitude. As such, it is likely to be at high risk of habitat loss and decreasing range, and we propose a status of Endangered for it. We discuss the a nities of these new species and the variability of calls in this genus

    Nuove segnalazioni di Zootoca vivipara Jaquin e di Vipera berus Linnaeus, in Piemonte, Italia nord-occidentale (Novitates Herpetologicae Pedemontanae II)

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    Vengono forniti nuovi dati distributivi di Zootoca vivipara e di Vipera berus in Piemonte (Italia nordoccidentale). La prima viene segnalata nelle valli Bognanco (VB), Sessera (BI), Mastallone (VC), Rimella (VC) e Strona (VB). Il Marasso viene invece segnalato per le valli Sorba (VC) e Strona (VB). I nuovi dati distributivi vengono commentati brevemente
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