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491.
Malia Chevolot Jim R. Ellis Galice Hoarau Adriaan D. Rijnsdorp Wytze T. Stam Jeanine L. Olsen 《Journal of Sea Research》2006,56(4):305-316
Prior to the 1950s, thornback ray (Raja clavata L.) was common and widely distributed in the seas of Northwest Europe. Since then, it has decreased in abundance and geographic range due to over-fishing. The sustainability of ray populations is of concern to fisheries management because their slow growth rate, late maturity and low fecundity make them susceptible to exploitation as victims of by-catch. We investigated the population genetic structure of thornback rays from 14 locations in the southern North Sea, English Channel and Irish Sea. Adults comprised < 4% of the total sampling despite heavy sampling effort over 47 hauls; thus our results apply mainly to sexually immature individuals. Using five microsatellite loci, weak but significant population differentiation was detected with a global FST = 0.013 (P < 0.001). Pairwise Fst was significant for 75 out of 171 comparisons. Although earlier tagging studies suggest restricted foraging distances from home areas, the absence of genetic differentiation between some distant populations suggests that a substantial fraction of individuals migrate over wide areas. Autumn/winter locations appear to have a lower level of differentiation than spring/summer, which could be due to seasonal migration. Management and conservation of thornback ray populations will be challenging as population structure appears to be dynamic in space and time. 相似文献
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Rodríguez-Cañero Rosario Jabaloy-Sánchez Antonio Navas-Parejo Pilar Martín-Algarra Agustín 《International Journal of Earth Sciences》2018,107(5):1791-1806
International Journal of Earth Sciences - Graphite-rich metamorphic limestones included within low-grade black schists of the lowest Nevado-Filábride tectonic unit in the Sierra de Baza... 相似文献
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Acta Geotechnica - Sinkhole occurrences due to underground water mains operations have piqued people’s curiosity. Most research works were in relation to geophysical practices to discover the... 相似文献
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Guimarães Pedro Veras Ardhuin Fabrice Perignon Yves Benetazzo Alvise Bouin Marie-Noëlle Garnier Valerie Redelsperger Jean-Luc Accensi Mickael Thomson Jim 《Ocean Dynamics》2022,72(8):621-639
Ocean Dynamics - Short waves growth is characterized by nonlinear and dynamic processes that couple ocean and atmosphere. Ocean surface currents can have a strong impact on short wave steepness and... 相似文献
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Vázquez R. Macías J. L. Alcalá-Reygosa J. Arce J. L. Jiménez-Haro A. Fernández S. Carlón T. Saucedo R. Sánchez-Núñez J. M. 《Natural Hazards》2022,110(2):1305-1337
Natural Hazards - Both climate and land-use changes can influence drought in different ways. Thus, to predict future drought conditions, hydrological simulations, as an ideal means, can be used to... 相似文献
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