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  1 / 3609 MEDLINE  
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[PMID]:29324879
[Au] Autor:Raoult V; Howell N; Zahra D; Peddemors VM; Howard DL; de Jonge MD; Buchan BL; Williamson JE
[Ad] Endereço:Department of Biological Sciences, Macquarie University, Sydney, NSW, Australia.
[Ti] Título:Localized zinc distribution in shark vertebrae suggests differential deposition during ontogeny and across vertebral structures.
[So] Source:PLoS One;13(1):e0190927, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The development of shark vertebrae and the possible drivers of inter- and intra-specific differences in vertebral structure are poorly understood. Shark vertebrae are used to examine life-history traits related to trophic ecology, movement patterns, and the management of fisheries; a better understanding of their development would be beneficial to many fields of research that rely on these calcified structures. This study used Scanning X-ray Fluorescence Microscopy to observe zinc distribution within vertebrae of ten shark species from five different orders. Zinc was mostly localised within the intermedialis and was generally detected at levels an order of magnitude lower in the corpus calcareum. In most species, zinc concentrations were higher pre-birth mark, indicating a high rate of pre-natal zinc deposition. These results suggest there are inter-specific differences in elemental deposition within vertebrae. Since the deposition of zinc is physiologically-driven, these differences suggest that the processes of growth and deposition are potentially different in the intermedialis and corpus calcareum, and that caution should be taken when extrapolating information such as annual growth bands from one structure to the other. Together these results suggest that the high inter-specific variation in vertebral zinc deposition and associated physiologies may explain the varying effectiveness of ageing methodologies applied to elasmobranch vertebrae.
[Mh] Termos MeSH primário: Envelhecimento/metabolismo
Tubarões/crescimento & desenvolvimento
Tubarões/metabolismo
Coluna Vertebral/crescimento & desenvolvimento
Coluna Vertebral/metabolismo
Zinco/metabolismo
[Mh] Termos MeSH secundário: Envelhecimento/patologia
Animais
Cálcio/metabolismo
Modelos Lineares
Microscopia de Fluorescência
Tubarões/anatomia & histologia
Especificidade da Espécie
Coluna Vertebral/diagnóstico por imagem
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
J41CSQ7QDS (Zinc); SY7Q814VUP (Calcium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180206
[Lr] Data última revisão:
180206
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180112
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0190927


  2 / 3609 MEDLINE  
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[PMID]:29182683
[Au] Autor:Marramà G; Kriwet J
[Ad] Endereço:Department of Palaeontology, University of Vienna, Vienna, Austria.
[Ti] Título:Principal component and discriminant analyses as powerful tools to support taxonomic identification and their use for functional and phylogenetic signal detection of isolated fossil shark teeth.
[So] Source:PLoS One;12(11):e0188806, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Identifying isolated teeth of fossil selachians only based on qualitative characters is sometimes hindered by similarity in their morphology, resulting often in heated taxonomic debates. On the other hand, the use of quantitative characters (i.e. measurements) has been often neglected or underestimated in characterization and identification of fossil teeth of selachians. Here we show that, employing a robust methodological protocol based on principal component and discriminant analyses on a sample of 175 isolated fossil teeth of lamniform sharks, the traditional morphometrics can be useful to support and complement the classic taxonomic identification made on qualitative features. Furthermore, we show that discriminant analysis can be successfully useful to assign indeterminate isolated shark teeth to a certain taxon. Finally, the degree of separation of the clusters might be used to predict functional and probably also phylogenetic signals in lamniform shark teeth. However, this needs to be tested in the future employing teeth of more extant and extinct lamniform sharks and it must be pointed out that this approach does not replace in any way the qualitative analysis, but it is intended to complement and support it.
[Mh] Termos MeSH primário: Fósseis
Tubarões/anatomia & histologia
Dente/anatomia & histologia
[Mh] Termos MeSH secundário: Animais
Análise Discriminante
Filogenia
Análise de Componente Principal
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171226
[Lr] Data última revisão:
171226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171129
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0188806


  3 / 3609 MEDLINE  
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[PMID]:28470783
[Au] Autor:Kryukova NV
[Ad] Endereço:Laboratory of morphological adaptations of vertebrates, Severtsov Institute of Ecology and Evolution, RAS, Moscow, 119071, Russia.
[Ti] Título:Functional analysis of the musculo-skeletal system of the gill apparatus in Heptranchias perlo (Chondrichthyes: Hexanchidae).
[So] Source:J Morphol;278(8):1075-1090, 2017 Aug.
[Is] ISSN:1097-4687
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Musculo-skeletal morphology is an indispensable source for understanding functional adaptations. Analysis of morphology of the branchial apparatus of Hexanchiform sharks can provide insight into aspects of their respiration that are difficult to observe directly. In this study, I compare the structure of the musculo-skeletal system of the gill apparatus of Heptranchias perlo and Squalus acanthias in respect to their adaptation for one of two respiratory mechanisms known in sharks, namely, the active two-pump (oropharyngeal and parabranchial) ventilation and the ram-jet ventilation. In both species, the oropharyngeal pump possesses two sets of muscles, one for compression and the other for expansion. The parabranchial pump only has constrictors. Expansion of this pump occurs only due to passive elastic recoil of the extrabranchial cartilages. In Squalus acanthias the parabranchial chambers are large and equipped by powerful superficial constrictors. These muscles and the outer walls of the parabranchial chambers are much reduced in Heptranchias perlo, and thus it likely cannot use this pump. However, this reduction allows for vertical elongation of outer gill slits which, along with greater number of gill pouches, likely decreases branchial resistance and, at the same time, increases the gill surface area, and can be regarded as an adaptation for ram ventilation at lower speeds.
[Mh] Termos MeSH primário: Brânquias/anatomia & histologia
Sistema Musculoesquelético/anatomia & histologia
Tubarões/anatomia & histologia
Tubarões/fisiologia
[Mh] Termos MeSH secundário: Animais
Osso e Ossos/anatomia & histologia
Cabeça/anatomia & histologia
Músculos/anatomia & histologia
Squalus acanthias/anatomia & histologia
Squalus acanthias/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171128
[Lr] Data última revisão:
171128
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE
[do] DOI:10.1002/jmor.20695


  4 / 3609 MEDLINE  
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[PMID]:29023598
[Au] Autor:Russo R; Giordano D; Paredi G; Marchesani F; Milazzo L; Altomonte G; Del Canale P; Abbruzzetti S; Ascenzi P; di Prisco G; Viappiani C; Fago A; Bruno S; Smulevich G; Verde C
[Ad] Endereço:Institute of Biosciences and BioResources, CNR, Via Pietro Castellino 111, Naples, Italy.
[Ti] Título:The Greenland shark Somniosus microcephalus-Hemoglobins and ligand-binding properties.
[So] Source:PLoS One;12(10):e0186181, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A large amount of data is currently available on the adaptive mechanisms of polar bony fish hemoglobins, but structural information on those of cartilaginous species is scarce. This study presents the first characterisation of the hemoglobin system of one of the longest-living vertebrate species (392 ± 120 years), the Arctic shark Somniosus microcephalus. Three major hemoglobins are found in its red blood cells and are made of two copies of the same α globin combined with two copies of three very similar ß subunits. The three hemoglobins show very similar oxygenation and carbonylation properties, which are unaffected by urea, a very important compound in marine elasmobranch physiology. They display identical electronic absorption and resonance Raman spectra, indicating that their heme-pocket structures are identical or highly similar. The quaternary transition equilibrium between the relaxed (R) and the tense (T) states is more dependent on physiological allosteric effectors than in human hemoglobin, as also demonstrated in polar teleost hemoglobins. Similar to other cartilaginous fishes, we found no evidence for functional differentiation among the three isoforms. The very similar ligand-binding properties suggest that regulatory control of O2 transport may be at the cellular level and that it may involve changes in the cellular concentrations of allosteric effectors and/or variations of other systemic factors. The hemoglobins of this polar shark have evolved adaptive decreases in O2 affinity in comparison to temperate sharks.
[Mh] Termos MeSH primário: Hemoglobinas/química
Hemoglobinas/metabolismo
Oxigênio/metabolismo
Tubarões/metabolismo
[Mh] Termos MeSH secundário: Animais
Monitoramento Ambiental
Groenlândia
Hemoglobinas/genética
Ligação Proteica
Conformação Proteica
Multimerização Proteica
Análise de Sequência de Proteína
Tubarões/genética
Análise Espectral Raman
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Hemoglobins); S88TT14065 (Oxygen)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171024
[Lr] Data última revisão:
171024
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171013
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0186181


  5 / 3609 MEDLINE  
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[PMID]:29020095
[Au] Autor:Cardeñosa D; Fields A; Abercrombie D; Feldheim K; Shea SKH; Chapman DD
[Ad] Endereço:School of Marine and Atmospheric Science, Stony Brook University, Stony Brook, New York, United States of America.
[Ti] Título:A multiplex PCR mini-barcode assay to identify processed shark products in the global trade.
[So] Source:PLoS One;12(10):e0185368, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Protecting sharks from overexploitation has become global priority after widespread population declines have occurred. Tracking catches and trade on a species-specific basis has proven challenging, in part due to difficulties in identifying processed shark products such as fins, meat, and liver oil. This has hindered efforts to implement regulations aimed at promoting sustainable use of commercially important species and protection of imperiled species. Genetic approaches to identify shark products exist but are typically based on sequencing or amplifying large DNA regions and may fail to work on heavily processed products in which DNA is degraded. Here, we describe a novel multiplex PCR mini-barcode assay based on two short fragments of the cytochrome oxidase I (COI) gene. This assay can identify to species all sharks currently listed on the Convention of International Trade of Endangered Species (CITES) and most shark species present in the international trade. It achieves species diagnosis based on a single PCR and one to two downstream DNA sequencing reactions. The assay is capable of identifying highly processed shark products including fins, cooked shark fin soup, and skin-care products containing liver oil. This is a straightforward and reliable identification method for data collection and enforcement of regulations implemented for certain species at all governance levels.
[Mh] Termos MeSH primário: Comércio
Código de Barras de DNA Taxonômico/métodos
Internacionalidade
Reação em Cadeia da Polimerase/métodos
Tubarões/genética
[Mh] Termos MeSH secundário: Nadadeiras de Animais/fisiologia
Animais
China
DNA/genética
Especificidade da Espécie
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
9007-49-2 (DNA)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171031
[Lr] Data última revisão:
171031
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171012
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0185368


  6 / 3609 MEDLINE  
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[PMID]:28972451
[Au] Autor:Giacomin M; Schulte PM; Wood CM
[Ti] Título:Differential Effects of Temperature on Oxygen Consumption and Branchial Fluxes of Urea, Ammonia, and Water in the Dogfish Shark (Squalus acanthias suckleyi).
[So] Source:Physiol Biochem Zool;90(6):627-637, 2017 Nov/Dec.
[Is] ISSN:1537-5293
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Environmental temperature can greatly influence the homeostasis of ectotherms through its effects on biochemical reactions and whole-animal physiology. Elasmobranchs tend to be N limited and are osmoconformers, retaining ammonia and urea-N at the gills and using the latter as a key osmolyte to maintain high blood osmolality. However, the effects of temperature on these key processes remain largely unknown. We evaluated the effects of acute exposure to different temperatures (7°, 12°, 15°, 18°, 22°C) on oxygen consumption, ammonia, urea-N, and diffusive water fluxes at the gills of Squalus acanthias suckleyi. We hypothesized that as metabolic demand for oxygen increased with temperature, the fluxes of ammonia, urea-N, and H O at the gills would increase in parallel with those of oxygen. Oxygen consumption (overall [Formula: see text] from 7.5° to 22°C) and water fluxes (overall [Formula: see text]) responded to increases in temperature in a similar, almost linear, manner. Ammonia-N efflux rates varied the most, increasing almost 15-fold from 7.5° to 22°C ([Formula: see text]). Urea-N efflux was tightly conserved over the 7.5°-15°C range ([Formula: see text]) but increased greatly at higher temperatures, yielding an overall [Formula: see text]. These differences likely reflect differences in the transport pathways for the four moieties. They also suggest the failure of urea-N- and ammonia-N-conserving mechanisms at the gill above 15°C. Hyperoxia did not alleviate the effects of high temperature. Indeed, urea-N and ammonia-N effluxes were dramatically increased when animals were exposed to high temperatures in the presence of hyperoxia, suggesting that high partial pressure of oxygen may have caused oxidative damage to gill epithelial membranes.
[Mh] Termos MeSH primário: Amônia/metabolismo
Consumo de Oxigênio/fisiologia
Tubarões/fisiologia
Temperatura Ambiente
Ureia/metabolismo
Água/metabolismo
[Mh] Termos MeSH secundário: Animais
Brânquias/fisiologia
Nitrogênio/metabolismo
Permeabilidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
059QF0KO0R (Water); 7664-41-7 (Ammonia); 8W8T17847W (Urea); N762921K75 (Nitrogen)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171018
[Lr] Data última revisão:
171018
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171004
[St] Status:MEDLINE
[do] DOI:10.1086/694296


  7 / 3609 MEDLINE  
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[PMID]:28945806
[Au] Autor:Engelbrecht T; Kock A; Waries S; O'Riain MJ
[Ad] Endereço:Institute for Communities and Wildlife in Africa, Department of Biological Sciences, University of Cape Town, Cape Town, South Africa.
[Ti] Título:Shark Spotters: Successfully reducing spatial overlap between white sharks (Carcharodon carcharias) and recreational water users in False Bay, South Africa.
[So] Source:PLoS One;12(9):e0185335, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:White sharks (Carcharodon carcharias) are apex predators that play an important role in the structure and stability of marine ecosystems. Despite their ecological importance and protected status, white sharks are still subject to lethal control to reduce the risk of shark bites for recreational water users. The Shark Spotters program, pioneered in Cape Town, South Africa, provides a non-lethal alternative for reducing the risk of human-shark conflict. In this study we assessed the efficacy of the Shark Spotters program in reducing overlap between water users and white sharks at two popular beaches in False Bay, South Africa. We investigated seasonal and diel patterns in water use and shark presence at each beach, and thereafter quantified the impact of different shark warnings from shark spotters on water user abundance. We also assessed the impact of a fatal shark incident on patterns of water use. Our results revealed striking diel and seasonal overlap between white sharks and water users at both beaches. Despite this, there was a low rate of shark-human incidents (0.5/annum) which we attribute partly to the success of the Shark Spotters program. Shark spotters use visual (coloured flags) and auditory (siren) cues to inform water users of risk associated with white shark presence in the surf zone. Our results showed that the highest risk category (denoted by a white flag and accompanying siren) caused a significant reduction in water user abundance; however the secondary risk category (denoted by a red flag with no siren) had no significant effect on water users. A fatal shark incident was shown to negatively impact the number of water users present for at least three months following the incident. Our results indicate that the Shark Spotters program effectively reduces spatial overlap between white sharks and water users when the risk of conflict is highest.
[Mh] Termos MeSH primário: Tubarões
Natação
[Mh] Termos MeSH secundário: Animais
Comportamento Animal
Mordeduras e Picadas/prevenção & controle
Ecossistema
Seres Humanos
Dinâmica Populacional
Comportamento Predatório
Recreação
Tubarões/fisiologia
África do Sul
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170926
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0185335


  8 / 3609 MEDLINE  
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[PMID]:28938002
[Au] Autor:Ferrón HG
[Ad] Endereço:Institut Cavanilles de Biodiversitat I Biologia Evolutiva, University of Valencia, Burjassot, Spain.
[Ti] Título:Regional endothermy as a trigger for gigantism in some extinct macropredatory sharks.
[So] Source:PLoS One;12(9):e0185185, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Otodontids include some of the largest macropredatory sharks that ever lived, the most extreme case being Otodus (Megaselachus) megalodon. The reasons underlying their gigantism, distribution patterns and extinction have been classically linked with climatic factors and the evolution, radiation and migrations of cetaceans during the Paleogene. However, most of these previous proposals are based on the idea of otodontids as ectothermic sharks regardless of the ecological, energetic and body size constraints that this implies. Interestingly, a few recent studies have suggested the possible existence of endothermy in these sharks thus opening the door to a series of new interpretations. Accordingly, this work proposes that regional endothermy was present in otodontids and some closely related taxa (cretoxyrhinids), playing an important role in the evolution of gigantism and in allowing an active mode of live. The existence of regional endothermy in these groups is supported here by three different approaches including isotopic-based approximations, swimming speed inferences and the application of a novel methodology for assessing energetic budget and cost of swimming in extinct taxa. In addition, this finding has wider implications. It calls into question some previous paleotemperature estimates based partially on these taxa, suggests that the existing hypothesis about the evolution of regional endothermy in fishes requires modification, and provides key evidence for understanding the evolution of gigantism in active macropredators.
[Mh] Termos MeSH primário: Tamanho Corporal/fisiologia
Tubarões/anatomia & histologia
Tubarões/fisiologia
[Mh] Termos MeSH secundário: Nadadeiras de Animais/anatomia & histologia
Animais
Evolução Biológica
Extinção Biológica
Fósseis
Gigantismo
Modelos Biológicos
Consumo de Oxigênio
Isótopos de Oxigênio/análise
Natação
Temperatura Ambiente
Dente/anatomia & histologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Oxygen Isotopes)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171017
[Lr] Data última revisão:
171017
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170923
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0185185


  9 / 3609 MEDLINE  
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[PMID]:28934371
[Au] Autor:Robinson DP; Jaidah MY; Bach SS; Rohner CA; Jabado RW; Ormond R; Pierce SJ
[Ad] Endereço:Heriot-Watt University, Edinburgh, United Kingdom.
[Ti] Título:Some like it hot: Repeat migration and residency of whale sharks within an extreme natural environment.
[So] Source:PLoS One;12(9):e0185360, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The Arabian Gulf is the warmest sea in the world and is host to a globally significant population of the whale shark Rhincodon typus. To investigate regional whale shark behaviour and movements, 59 satellite-linked tags were deployed on whale sharks in the Al Shaheen area off Qatar from 2011-14. Four different models of tag were used throughout the study, each model able to collect differing data or quantities of data. Retention varied from one to 227 days. While all tagged sharks crossed international maritime boundaries, they typically stayed within the Arabian Gulf. Only nine sharks dispersed through the narrow Strait of Hormuz into the Gulf of Oman. Most sharks stayed close to known or suspected feeding aggregation sites over summer months, but dispersed throughout the Arabian Gulf in winter. Sharks rarely ventured into shallow areas (<40 m depth). A single, presumably pregnant female shark was the sole animal to disperse a long distance, crossing five international maritime boundaries in 37 days before the tag detached at a distance of approximately 2644 km from the tagging site, close to the Yemeni-Somali border. No clear space-use differentiation was evident between years, for sharks of different sizes, or between sexes. Whale sharks spent the most time (~66%) in temperatures of 24-30°C and in shallow waters <100 m depth (~60%). Sharks spent relatively more time in cooler (X2 = 121.692; p<0.05) and deeper (X2 = 46.402; p<0.05) water at night. Sharks rarely made dives deeper than 100 m, reflecting the bathymetric constraints of the Gulf environment. Kernel density analysis demonstrated that the tagging site at Al Shaheen was the regional hotspot for these sharks, and revealed a probable secondary aggregation site for whale sharks in nearby Saudi Arabian waters. Analysis of visual re-sightings data of tagged sharks revealed that 58% of tagged individuals were re-sighted back in Al Shaheen over the course of this study, with 40% recorded back at Al Shaheen in the year following their initial identification. Two sharks were confirmed to return to Al Shaheen in each of the five years of study.
[Mh] Termos MeSH primário: Migração Animal
Temperatura Alta
Tubarões
[Mh] Termos MeSH secundário: Animais
Comportamento Animal
Ecossistema
Feminino
Masculino
Estações do Ano
Astronave
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171018
[Lr] Data última revisão:
171018
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170922
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0185360


  10 / 3609 MEDLINE  
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[PMID]:28926627
[Au] Autor:Afonso AS; Garla R; Hazin FHV
[Ad] Endereço:Departamento de Pesca e Aquicultura, Universidade Federal Rural de Pernambuco, Recife, Pernambuco, Brazil.
[Ti] Título:Tiger sharks can connect equatorial habitats and fisheries across the Atlantic Ocean basin.
[So] Source:PLoS One;12(9):e0184763, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Increasing our knowledge about the spatial ecology of apex predators and their interactions with diverse habitats and fisheries is necessary for understanding the trophic mechanisms that underlie several aspects of marine ecosystem dynamics and for guiding informed management policies. A preliminary assessment of tiger shark (Galeocerdo cuvier) population structure off the oceanic insular system of Fernando de Noronha (FEN) and the large-scale movements performed by this species in the equatorial Atlantic Ocean was conducted using longline and handline fishing gear and satellite telemetry. A total of 25 sharks measuring 175-372 cm in total length (TL) were sampled. Most sharks were likely immature females ranging between 200 and 260 cm TL, with few individuals < 200 cm TL being caught. This contrasts greatly with the tiger shark size-distribution previously reported for coastal waters off the Brazilian mainland, where most individuals measured < 200 cm TL. Also, the movements of 8 individuals measuring 202-310 cm TL were assessed with satellite transmitters for a combined total of 757 days (mean = 94.6 days∙shark-1; SD = 65.6). These sharks exhibited a considerable variability in their horizontal movements, with three sharks showing a mostly resident behavior around FEN during the extent of the respective tracks, two sharks traveling west to the South American continent, and two sharks moving mostly along the middle of the oceanic basin, one of which ending up in the northern hemisphere. Moreover, one shark traveled east to the African continent, where it was eventually caught by fishers from Ivory Coast in less than 474 days at liberty. The present results suggest that young tiger sharks measuring < 200 cm TL make little use of insular oceanic habitats from the western South Atlantic Ocean, which agrees with a previously-hypothesized ontogenetic habitat shift from coastal to oceanic habitats experienced by juveniles of this species in this region. In addition, this study adds evidence that tiger sharks are able to connect marine trophic webs from the neritic provinces of the eastern and western margins of the Atlantic Ocean across the equatorial basin and that they may experience mortality induced by remote fisheries. All this information is extremely relevant for understanding the energetic balance of marine ecosystems as much as the exposure of this species to fishing pressure in this yet poorly-known region.
[Mh] Termos MeSH primário: Ecossistema
Tubarões/fisiologia
[Mh] Termos MeSH secundário: Animais
Oceano Atlântico
Comportamento Animal
Tamanho Corporal
Feminino
Pesqueiros
Sistemas de Informação Geográfica
Masculino
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171020
[Lr] Data última revisão:
171020
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170920
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0184763



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