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Auteur (up) Espinosa, F.; Rivera-Ingraham, G.A.
Titre Biological Conservation of Giant Limpets: The Implications of Large Size Type Chapitre de livre
Année 2017 Publication Revue Abrégée
Volume Numéro Pages 105-155
Mots-Clés cymbula-nigra gastropoda; endangered limpet; lottia-gigantea; marine protected areas; mussel mytilus-galloprovincialis; patella-ferruginea gastropoda; population-structure; scutellastra-argenvillei; sex-change; south-african limpet
Résumé Patellogastropods, also known as true limpets, are distributed throughout the world and constitute key species in coastal ecosystems. Some limpet species achieve remarkable sizes, which in the most extreme cases can surpass 35 cm in shell length. In this review, we focus on giant limpets, which are defined as those with a maximum shell size surpassing 10 cm. According to the scientific literature, there are a total of 14 species across five genera that reach these larger sizes. Four of these species are threatened or in danger of extinction. Inhabiting the intertidal zones, limpets are frequently affected by anthropogenic impacts, namely collection by humans, pollution and habitat fragmentation. In the case of larger species, their conspicuous size has made them especially prone to human collection since prehistoric times. Size is not phylogeny-dependent among giant limpets, but is instead related to behavioural traits instead. Larger-sized species tend to be nonmigratory and territorial compared to those that are smaller. Collection by humans has been cited as the main cause behind the decline and/or extinction of giant limpet populations. Their conspicuously large size makes them the preferred target of human collection. Because they are protandric species, selectively eliminating larger specimens of a given population seriously compromises their viability and has led to local extinction events in some cases. Additionally, sustained collection over time may lead to microevolutionary responses that result in genetic changes. The growing presence of artificial structures in coastal ecosystems may cause population fragmentation and isolation, limiting the genetic flow and dispersion capacity of many limpet species. However, when they are necessitated, artificial structures could be managed to establish marine artificial microreserves and contribute to the conservation of giant limpet species that naturally settle on them.
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Auteur institutionnel Thèse
Editeur Elsevier Academic Press Inc Lieu de Publication San Diego Éditeur Curry, B.E.
Langue English Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé Advances in Marine Biology, Vol 76
Volume de collection 76 Numéro de collection Edition
ISSN ISBN 978-0-12-812402-4 978-0-12-812401-7 Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ alain.herve @ collection 2180
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Auteur (up) Lagabrielle, E.; Allibert, A.; Kiszka, J.J.; Loiseau, N.; Kilfoil, J.P.; Lemahieu, A.
Titre Environmental and anthropogenic factors affecting the increasing occurrence of shark-human interactions around a fast-developing Indian Ocean island Type Article scientifique
Année 2018 Publication Revue Abrégée Sci Rep
Volume 8 Numéro Pages 3676
Mots-Clés coral-reefs; south-africa; florida; western-australia; carcharhinus-leucas; movement patterns; attack; bull shark; la reunion; reunion-island
Résumé Understanding the environmental drivers of interactions between predators and humans is critical for public safety and management purposes. In the marine environment, this issue is exemplified by shark-human interactions. The annual shark bite incidence rate (SBIR) in La Reunion (Indian Ocean) is among the highest in the world (up to 1 event per 24,000 hours of surfing) and has experienced a 23-fold increase over the 2005-2016 period. Since 1988, 86% of shark bite events on ocean-users involved surfers off the leeward coast, where 96% of surfing activities took place. We modeled the SBIR as a function of environmental variables, including benthic substrate, sea temperature and period of day. The SBIR peaked in winter, during the afternoon and dramatically increased on coral substrate since the mid-2000s. Seasonal patterns of increasing SBIR followed similar fluctuations of large coastal shark occurrences (particularly the bull shark Carcharhinus leucas), consistent with the hypothesis that higher shark presence may result in an increasing likelihood of shark bite events. Potential contributing factors and adaptation of ocean-users to the increasing shark bite hazard are discussed. This interdisciplinary research contributes to a better understanding of shark-human interactions. The modeling method is relevant for wildlife hazard management in general.
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Auteur institutionnel Thèse
Editeur Lieu de Publication Éditeur
Langue English Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 2045-2322 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ alain.herve @ collection 2314
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Auteur (up) Trystram, C.; Rogers, K.M.; Soria, M.; Jaquemet, S.
Titre Feeding patterns of two sympatric shark predators in coastal ecosystems of an oceanic island Type Article scientifique
Année 2017 Publication Revue Abrégée Can. J. Fish. Aquat. Sci.
Volume 74 Numéro 2 Pages 216-227
Mots-Clés Bull shark; carcharhinus-leucas; elasmobranch fishes; galeocerdo-cuvier; individual specialization; Reunion island; south-africa; stable-isotope analyses; tiger shark; western indian-ocean
Résumé Stomach contents and stable carbon and nitrogen isotope analyses (delta C-13 and delta N-15) were used to investigate the trophic ecology of two apex predators, tiger sharks (Galeocerdo cuvier) and bull sharks (Carcharhinus leucas), from Reunion Island to describe their dietary habits at both the population and individual levels. In this oceanic island, the tiger and bull sharks were more piscivorous and teutophagous than noted in previous research from other localities. The delta C-13 values suggested that bull sharks depended on more neritic organic matter sources than tiger sharks, confirming a coastal habitat preference for bull sharks. Moreover, the total length of the bull shark influenced delta C-13 values, with smaller individuals being more coastal than larger individuals. All indicators suggest that there is a higher degree of similarity between individual tiger sharks compared with the more heterogeneous bull shark population, which is composed of individuals who specialize on different prey. These results suggest that the two species have different functions in these coastal habitats, and thus, they must be considered independently in terms of conservation and management.
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Auteur institutionnel Thèse
Editeur Lieu de Publication Éditeur
Langue English Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0706-652x ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ alain.herve @ collection 2111
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