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Auteur Borsa, P.; Durand, J.D.; Shen, K.N.; Arlyza, I.S.; Solihin, D.D.; Berrebi, P.
Titre Himantura tutul sp nov (Myliobatoidei: Dasyatidae), a new ocellated whipray from the tropical Indo-West Pacific, described from its cytochrome-oxidase I gene sequence Type Article scientifique
Année 2013 Publication Revue Abrégée Comptes Rendus Biologies
Volume 336 Numéro 2 Pages 82-92
Mots-Clés Himantura leoparda, New species, Molecular taxonomy, COI, Cytochrome b; myliobatiformes dasyatidae, conservation, fisheries, indonesia, sharks,; rays, elasmobranchs, management, taxonomy, barcode
Résumé It has been previously established that the Leopard Whipray, Himantura leoparda, consists of two genetically isolated, cryptic species, provisionally designated as 'Cluster 1' and 'Cluster 4' (Arlyza et al., Mol. Phylogenet. Evol. 65 (2013) [11). Here, we show that the two cryptic species differ by the spotting patterns on the dorsal surface of adults: Cluster-4 individuals tend to have larger-ocellated spots, which also more often have a continuous contour than Cluster-1 individuals. We show that H. leopard a's holotype has the typical larger-ocellated spot pattern, designating Cluster 4 as the actual H. leoparda. The other species (Cluster 1) is described as Himantura tutul sp. nov. on the basis of the nucleotide sequence of a 655-base pair fragment of its cytochrome-oxidase I gene (GENBANK accession No. JX263335). Nucleotide synapomorphies at this locus clearly distinguish H. tutul sp. nov. from all three other valid species in the H. uarnak species complex, namely H. leoparda, H. uarnak, and H. undulata. H. tutul sp. nov. has a wide distribution in the Indo-West Pacific, from the shores of eastern Africa to the Indo-Malay archipelago. H. leoparda under its new definition has a similarly wide Indo-West Pacific distribution. (C) 2013 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.
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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 1631-0691 ISBN Médium
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 624
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Auteur Coelho, R.; Mejuto, J.; Domingo, A.; Yokawa, K.; Liu, K.-M.; Cortes, E.; Romanov, E.V.; da Silva, C.; Hazin, F.; Arocha, F.; Mwilima, A.M.; Bach, P.; Ortiz de Zarate, V.; Roche, W.; Lino, P.G.; Garcia-Cortes, B.; Ramos-Cartelle, A.M.; Forselledo, R.; Mas, F.; Ohshimo, S.; Courtney, D.; Sabarros, P.S.; Perez, B.; Wogerbauer, C.; Tsai, W.-P.; Carvalho, F.; Santos, M.N.
Titre Distribution patterns and population structure of the blue shark (Prionace glauca) in the Atlantic and Indian Oceans Type Article scientifique
Année 2018 Publication Revue Abrégée Fish. Fish.
Volume 19 Numéro 1 Pages 90-106
Mots-Clés Atlantic Ocean; Indian Ocean; size distribution; spatial distribution; relative abundance; north-atlantic; caribbean sea; elasmobranchs caught; fishery observer programmes; pelagic fisheries; pelagic sharks
Résumé The blue shark (Prionace glauca) is the most frequently captured shark in pelagic oceanic fisheries, especially pelagic longlines targeting swordfish and/or tunas. As part of cooperative scientific efforts for fisheries and biological data collection, information from fishery observers, scientific projects and surveys, and from recreational fisheries from several nations in the Atlantic and Indian Oceans was compiled. Data sets included information on location, size and sex, in a total of 478,220 blue shark records collected between 1966 and 2014. Sizes ranged from 36 to 394cm fork length. Considerable variability was observed in the size distribution by region and season in both oceans. Larger blue sharks tend to occur in equatorial and tropical regions, and smaller specimens in higher latitudes in temperate waters. Differences in sex ratios were also detected spatially and seasonally. Nursery areas in the Atlantic seem to occur in the temperate south-east off South Africa and Namibia, in the south-west off southern Brazil and Uruguay, and in the north-east off the Iberian Peninsula and the Azores. Parturition may occur in the tropical north-east off West Africa. In the Indian Ocean, nursery areas also seem to occur in temperate waters, especially in the south-west Indian Ocean off South Africa, and in the south-east off south-western Australia. The distributional patterns presented in this study provide a better understanding of how blue sharks segregate by size and sex, spatially and temporally, and improve the scientific advice to help adopt more informed and efficient management and conservation measures for this cosmopolitan species.
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Volume de collection Numéro de collection Edition
ISSN 1467-2960 ISBN Médium
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Numéro d'Appel MARBEC @ alain.herve @ collection 2253
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Auteur Follesa, M.C.; Marongiu, M.F.; Zupa, W.; Bellodi, A.; Cau, A.; Cannas, R.; Colloca, F.; Djurovic, M.; Isajlovic, I.; Jadaud, A.; Manfredi, C.; Mulas, A.; Peristeraki, P.; Porcu, C.; Ramirez-Amaro, S.; Salmeron Jimenez, F.; Serena, F.; Sion, L.; Thasitis, I.; Cau, A.; Carbonara, P.
Titre Spatial variability of Chondrichthyes in the northern Mediterranean Type Article scientifique
Année 2019 Publication Revue Abrégée Sci. Mar.
Volume 83 Numéro Pages 81-100
Mots-Clés abundance; adriatic sea; balearic-islands; bottom trawl surveys; by-catch; Chondrichthyes; demersal assemblages; depth distribution; distribution; dynamics; elasmobranchs; fish; fisheries; Mediterranean; parameters; patterns
Résumé Thanks to the availability of the MEDITS survey data, a standardized picture of the occurrence and abundance of demersal Chondrichthyes in the northern Mediterranean has been obtained. During the spring-summer period between 2012 and 2015, 41 Chondrichthyes, including 18 sharks (5 orders and 11 families). 22 batoids (3 orders and 4 families) and 1 chimaera, were detected from several geographical sub-areas (GSAs) established by the General Fisheries Commission for the Mediterranean. Batoids had a preferential distribution on the continental shelf (10-200 m depth). while shark species were more frequent on the slope (200-800 m depth). Only three species, the Carcharhiniformes Galeus melastomus and Scyliorhinus canicida and the Torpediniformes Torpedo matmorata were caught in all GSAs studied. On the continental shelf, the Rajidae family was the most abundant, being represented in primis by Raja clavaia and then by R. miraleius, R. polystigma and R. asterias. The slope was characterized by the prevalence of G. melastomus in all GSAs, followed by S. canictda, E. spinax and Squalus blainville. Areas under higher fishing pressure, such as the Adriatic Sea and the Spanish coast (with the exception of the Balearic Islands), show a low abundance of chondrichthyans, but other areas with a high level of fishing pressure, such as southwestern Sicily, show a high abundance, suggesting that other environmental drivers work together with fishing pressure to shape their distribution. Results of generalized additive models highlighted that depth is one of the most important environmental drivers influencing the distribution of both batoid and shark species, although temperature also showed a significant influence on their distribution. The approach explored in this work shows the possibility of producing maps modelling the distribution of demersal chondrichthyans in the Mediterranean that are useful for the management and conservation of these species at a regional scale. However, because of the vulnerability of these species to fishing exploitation, fishing pressure should be further incorporated in these models in addition to these environmental drivers.
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Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0214-8358 ISBN Médium
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Notes WOS:000504829900007 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2700
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Auteur Matich, P.; Kiszka, J.J.; Heithaus, M.R.; Le Bourg, B.; Mourier, J.
Titre Inter-individual differences in ontogenetic trophic shifts among three marine predators Type Article scientifique
Année 2019 Publication Revue Abrégée Oecologia
Volume 189 Numéro 3 Pages 621-636
Mots-Clés body-size; bull shark; carcharhinus-leucas; delta-n-15 values; Dietary shifts; Elasmobranchs; Foraging development; individual variation; intertissue comparisons; Juveniles; life-history traits; niche shifts; Nursery; specialization; stable-isotopes
Résumé Ontogenetic niche shifts are widespread. However, individual differences in size at birth, morphology, sex, and personalities can cause variability in behavior. As such, inherent inter-individual differences within populations may lead to context-dependent changes in behavior with animal body size, which is of concern for understanding population dynamics and optimizing ecological monitoring. Using stable carbon and nitrogen isotope values from concurrently sampled tissues, we quantified the direction and magnitude of intraspecific variation in trophic shifts among three shark species, and how these changed with body size: spurdogs (Squalus spp.) in deep-sea habitats off La Reunion, bull sharks (Carcharhinus leucas) in estuarine habitats of the Florida Everglades, and blacktip reef sharks (Carcharhinus melanopterus) in coral reef ecosystems of Moorea, French Polynesia. Intraspecific variation in trophic shifts was limited among spurdogs, and decreased with body size, while bull sharks exhibited greater individual differences in trophic shifts, but also decreased in variability through ontogeny. In contrast, blacktip reef sharks exhibited increased intraspecific variation in trophic interactions with body size. Variability in trophic interactions and ontogenetic shifts are known to be associated with changes in energetic requirements, but can vary with ecological context. Our results suggest that environmental stability may affect variability within populations, and ecosystems with greater spatial and/or temporal variability in environmental conditions, and those with more diverse food webs may facilitate greater individual differences in trophic interactions, and thus ontogenetic trophic shifts. In light of concerns over environmental disturbance, elucidating the contexts that promote or dampen phenotypic variability is invaluable for predicting population- and community-level responses to environmental changes.
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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 0029-8549 ISBN Médium
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2547
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Auteur Navarro, J.; Cardador, L.; Fernández, Á.M.; Bellido, J.M.; Coll, M.
Titre Differences in the relative roles of environment, prey availability and human activity in the spatial distribution of two marine mesopredators living in highly exploited ecosystems Type Article scientifique
Année 2016 Publication Revue Abrégée J. Biogeogr.
Volume 43 Numéro 3 Pages 440-450
Mots-Clés deviance partitioning; elasmobranchs; environmental variables; human stressors; indicator species; marine biodiversity; Marine conservation; Mediterranean Sea; Raja asterias; Scyliorhinus canicula
Résumé Aim Identifying the main factors affecting the spatial distribution of marine predators is essential in order to evaluate their distribution patterns, predict the potential impact of human activities on their populations and design accurate management actions. This information is also valuable from a more general management perspective, as marine predators are often considered indicators of habitat quality. In this context, we aimed to determine the degree to which environmental features, prey availability and human activities interact and influence spatial distribution of two marine mesopredator elasmobranchs, the small-spotted catshark (Scyliorhinus canicula) and the Mediterranean starry ray (Raja asterias), living in a highly human-exploited environment. Location Mediterranean Sea. Methods With information obtained from an extended experimental survey, we investigated the relative importance of environmental variables, prey availability and human activities on the spatial distribution of the abundance, biomass and occurrence rate of these marine mesopredators using deviance partitioning analyses. Results Our results revealed that environmental variables were the most important factors explaining the spatial distribution of Mediterranean starry ray, whereas small-spotted catshark distribution was also influenced by prey availability and human factors. From a management point of view, these findings suggest that Mediterranean starry ray could be a good candidate as an indicator species of demersal environmental quality. On the other hand, the distribution of the small-spotted catshark, which responds in an interactive and complex way to environment, prey availability and particular human activities, may be misleading as an environmental indicator. Main conclusions The spatial distribution of elasmobranchs in highly human-impacted marine areas can reflect the interactive and combined effects of multiple factors. To avoid misunderstandings, attention should be paid to statistical procedures allowing the separation of pure and joint contribution of the factors driving the observed spatial patterns.
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Volume de collection Numéro de collection Edition
ISSN 1365-2699 ISBN Médium
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Numéro d'Appel MARBEC @ alain.herve @ collection 1538
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