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Douglas L.R.,University of the West Indies | Douglas L.R.,CNRS Center for Marine Biodiversity, Exploitation and Conservation | Alie K.,Wildlife Trade Program
Biological Conservation | Year: 2014

The relationship between natural resources and conflict is well documented, except for wildlife. We discuss the role that wildlife can play in national and international security interests, including wildlife's role in financing the activities of belligerent groups and catalyzing social conflict. We argue that, similar to the findings for other high-value natural resources, wildlife can have a powerful influence on violent conflicts and security interests, particularly in developing and weak states, where the earth's biological resources are disproportionately found. We suggest that recognizing this relationship is important because it illuminates the gravity of the threat facing several charismatic species. The association also illuminates a neglected link between wildlife conservation and high-priority security and development policy concerns. We advocate that documenting and deconstructing the relationship between the wildlife trade and international crime, armed conflict, security, and development concerns within the context of our knowledge of other high-value natural resources has policy and management implications of great important in conservation practice. © 2014 Elsevier Ltd. Source

Lefevre S.,University of Oslo | Bayley M.,University of Aarhus | Mckenzie D.J.,CNRS Center for Marine Biodiversity, Exploitation and Conservation | Mckenzie D.J.,Federal University of Sao Carlos
Journal of Fish Biology | Year: 2016

Respirometry is a robust method for measurement of oxygen uptake as a proxy for metabolic rate in fishes, and how species with bimodal respiration might meet their demands from water v. air has interested researchers for over a century. The challenges of measuring oxygen uptake from both water and air, preferably simultaneously, have been addressed in a variety of ways, which are briefly reviewed. These methods are not well-suited for the long-term measurements necessary to be certain of obtaining undisturbed patterns of respiratory partitioning, for example, to estimate traits such as standard metabolic rate. Such measurements require automated intermittent-closed respirometry that, for bimodal fishes, has only recently been developed. This paper describes two approaches in enough detail to be replicated by the interested researcher. These methods are for static respirometry. Measuring oxygen uptake by bimodal fishes during exercise poses specific challenges, which are described to aid the reader in designing experiments. The respiratory physiology and behaviour of air-breathing fishes is very complex and can easily be influenced by experimental conditions, and some general considerations are listed to facilitate the design of experiments. Air breathing is believed to have evolved in response to aquatic hypoxia and, probably, associated hypercapnia. The review ends by considering what realistic hypercapnia is, how hypercapnic tropical waters can become and how this might influence bimodal animals' gas exchange. © 2016 The Fisheries Society of the British Isles. Source

Nichols E.,University of Sao Paulo | Nichols E.,Lancaster University | Gomez A.,CNRS Center for Marine Biodiversity, Exploitation and Conservation
Parasitology | Year: 2014

Dung beetles are detrivorous insects that feed on and reproduce in the fecal material of vertebrates. This dependency on vertebrate feces implies frequent contact between dung beetles and parasitic helminths with a fecal component to their life-cycle. Interactions between dung beetles and helminths carry both positive and negative consequences for successful parasite transmission, however to date there has been no systematic review of dung beetle-helminth interactions, their epidemiological importance, or their underlying mechanisms. Here we review the observational evidence of beetle biodiversity-helminth transmission relationships, propose five mechanisms by which dung beetles influence helminth survival and transmission, and highlight areas for future research. Efforts to understand how anthropogenic impacts on biodiversity may influence parasite transmission must include the development of detailed, mechanistic understanding of the multiple interactions between free-living and parasitic species within ecological communities. The dung beetle-helminth system may be a promising future model system with which to understand these complex relationships. © 2014 Cambridge University Press. Source

Gibbs J.P.,New York University | Sterling E.J.,CNRS Center for Marine Biodiversity, Exploitation and Conservation | Zabala F.J.,Charles Darwin Research Station
Biotropica | Year: 2010

Giant tortoises were once a megafaunal element widespread in tropical and subtropical ecosystems. The role of giant tortoises as herbivores and seed dispersers, however, is poorly known. We evaluated tortoise impacts on Opuntia cactus (Cactaceae) in the Galápagos Islands, one of the last areas where giant tortoises remain extant, where the cactus is a keystone resource for many animals. We contrasted cactus populations immediately inside and outside natural habitats where tortoises had been held captive for several decades. Through browsing primarily and trampling secondarily tortoises strongly reduced densities of small (0.5-1.5 m high) cacti, especially near adult cacti, and thereby reduced densities of cacti in larger size classes. Tortoises also caused a shift from vegetative to sexual modes of reproduction in cacti. We conclude that giant tortoises promote a sparse and scattered distribution in Opuntia cactus and its associated biota in the Galápagos Islands. 2009 The Author(s). Journal compilation © 2009 by The Association for Tropical Biology and Conservation. Source

Bain R.H.,Canadian Museum of Nature | Hurley M.M.,CNRS Center for Marine Biodiversity, Exploitation and Conservation
Bulletin of the American Museum of Natural History | Year: 2011

Indochina (Laos, Cambodia, and Vietnam) houses over 600 species of amphibians and reptiles, roughly a quarter of which has been described within the last 15 years. Herein, we undertake the first biogeographic synthesis of the regional herpetofauna since the first half of the 20th century. We review the literature to measure and map species richness and endemism, the contributions of regional faunas, and ecological characteristics of Indochina's amphibians (Anura, Caudata), and reptiles (Serpentes, Sauria, Testudines, Crocodylia). Dividing Indochina into 19 subregions defined by topography and geology, we estimate the similarity among the regional faunas and appraise the effects of area and survey effort on these comparative analyses. Variation in species composition is broadly correlated with topography, habitat complexity, and proximity to regions outside Indochina. Indochina's herpetofauna is dominated (in decreasing order) by endemic species, widely distributed species, a South China fauna, and a biota centered in Thailand and Myanmar. Species richness is highest in amphibians and snakes, and peaks in upland forests. Endemism, highest among amphibians and lizards, also peaks in forests of the region's northern uplands and Annamite Range. Endemic species occupy a narrower range of habitats than nonendemics. Patterns of richness and endemism are partially explained by ecological constraints: amphibians and lizards are more restricted to forests than snakes, turtles, and crocodiles; amphibians are more restricted to uplands, turtles to lowlands. We also assess biogeography in the context of Indochina's geology, climate, and land cover. In northern Indochina, the Red River either acts as or coincides with an apparent dispersal barrier. Herpetofauna in northeastern upland areas are closely allied with fauna of southeastern China. In southern Indochina there is little evidence that the Mekong River represents a biogeographic barrier to the regional herpetofauna. The Annamite Range is composed of at least three distinct units and its elevated species richness and endemism are also noted in adjacent lowlands. Contribution of subtropical biota to Indochina's fauna is significantly greater than that of tropical biota and there is little other evidence for intermixing at intermediate latitudes. Our results have implications for biogeography and conservation efforts, although they must be viewed in the context of rapidly evolving systematic knowledge of the region's amphibians and reptiles. Future survey efforts, and the phylogenetic analyses that come from them, are essential for supporting regional conservation efforts, as they will better resolve the known patterns of amphibian and reptile richness and endemism. © 2011 American Museum of Natural History. Source

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