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Registros recuperados: 75 | |
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Read, Andrew J; Duke University; aread@duke.edu; Brownstein, Carrie R; Duke University; cbrownstein@audubon.org. |
After decades of overexploitation and severe depletion, Atlantic herring stocks in waters of the northeastern United States have recovered. Fishery managers now consider the herring resource to be underexploited. Nevertheless, some fishery managers and sustainable fishery advocates in New England have expressed concern that the fishery management plan may not adequately consider the importance of herring as prey for marine mammals, seabirds, and piscivorous fish. Several studies suggest that consumption by these predators is significant, yet trophic interactions are not explicitly considered in stock assessment models. Instead, as in most fisheries stock assessments, predation is subsumed within the natural mortality rate, and no empirical estimates of... |
Tipo: Peer-Reviewed Reports |
Palavras-chave: Atlantic herring; Ecosystem management; Fisheries management; Gulf of Maine; Marine mammals; Piscivores; Protected species; Single-species approach; Stock assessment; Trophic interactions. |
Ano: 2003 |
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Lahaye, V; Bustamante, Paco; Dabin, W; Churlaud, C; Caurant, Florence. |
Tissues of foetus-mother pairs of common dolphins (Delphinus delphis) stranded along the French coasts (Bay of Biscay and English Channel) were analysed for their Cd, Cu, Hg, Se and Zn contents. In the kidneys, foetal Cd levels were extremely low, and strong relationships between Cu and Zn suggested the involvement of metallothioneins since early foetal life. The results also indicated a limited maternal transfer of Hg during pregnancy since levels in the tissues of foetuses were below 1 mu g g(-1) w.wt. However, hepatic Hg levels in foetuses increased with body length, and were also proportionate to maternal hepatic, renal and muscular Hg levels. Lastly, affinities between Hg and Se in tissues would participate in Hg neutralisation in both mothers-through... |
Tipo: Text |
Palavras-chave: North eastern Atlantic; Pregnancy; Selenium; Mercury; Marine mammals. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3691.pdf |
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Galgani, Francois; Claro, F.; Depledge, M.; Fossi, C.. |
In its decision (2010/477/EU) relating to the European Marine Strategy Framework Directive (MSFD, 2008/56/EC), the European Commission identified the following points as focuses for monitoring: (i) 10.1.1: Trends in the amount, source and composition of litter washed ashore and/or deposited on coastlines, (ii) 10.1.2: Trends in the amount and composition of litter in the water column and accumulation on the sea floor, (iii) 10.1.3: Trends in the amount, distribution and composition of micro-particles (mainly microplastics), and (iv) 10.2.1 Trends in the amount and composition of litter ingested by marine animals. Monitoring the impacts of litter will be considered further in 2014. At that time, the strategy will be discussed in the context of the... |
Tipo: Text |
Palavras-chave: Marine litter; MSFD; Good Environmental Status; Monitoring; Sea turtles; Marine mammals; Seabirds; Fulmar. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00177/28822/27299.pdf |
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Spitz, Jerome; Ridoux, Vincent; Brind'Amour, Anik. |
1. Understanding ‘Why a prey is a prey for a given predator?’ can be facilitated through trait-based approaches that identify linkages between prey and predator morphological and ecological characteristics and highlight key functions involved in prey selection. 2. Enhanced understanding of the functional relationships between predators and their prey is now essential to go beyond the traditional taxonomic framework of dietary studies and to improve our knowledge of ecosystem functioning for wildlife conservation and management. 3. We test the relevance of a three-matrix approach in foraging ecology among a marine mammal community in the northeast Atlantic to identify the key functional traits shaping prey selection processes regardless of the taxonomy... |
Tipo: Text |
Palavras-chave: Foraging strategy; Fourth-corner method; Functional ecology; Marine mammals; Prey selection; RLQ analysis. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00189/30047/29495.pdf |
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Lurton, Xavier. |
Multi-Beam Echo-Sounders (MBES) designed for seafloor-mapping applications are today a major tool for ocean exploration and monitoring. Concerns have been raised about their impact towards marine life and especially marine mammals, although their inherent characteristics (high frequencies, short signals and narrow transmitting lobes) actually minimize this possibility. The present paper proposes an analysis of MBES radiation characteristics (pulse design, source level and radiation directivity pattern) accounting for the various geometries met today and expressed according to the metrics used for acoustical impact assessment (maximum Sound Pressure Level, and cumulative Sound Exposure Level). A detailed radiation model is proposed, including the... |
Tipo: Text |
Palavras-chave: Multibeam echosounders; Marine mammals; Sonar impact assessment; Sound Pressure Level; Sound Exposure Level; Directivity pattern. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00278/38957/37497.pdf |
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Abarnou, Alain; Robineau, Daniel; Michel, Pierre. |
Top predators like marine mammals have been intensively used for monitoring the contamination of the marine environment, particularly in industrialized coastal areas of the Northern Atlantic Ocean. Such data concerning contamination in the Southern hemisphere are very scarce. Samples were taken in the fatty protuberance of the forehead (melon) from eleven Commerson's dolphins (Cephalorhynchus commersonii, Lacépède, 1804) caught in the coastal waters of the Kerguelen Islands (Southern Indian Ocean). They were analyzed for DDT, PCB and HCB, using capillary gaz chromatography. The levels of contamination [DDT= 1 150 ± 650, PCB = 1 150 ± 770, HCB=500±300ng/g of extracted matter (lipids)] are between ten and a hundred times Jess than those found in similar... |
Tipo: Text |
Palavras-chave: Organochlorés; Mammifères marins; Océan austral; Iles Kerguelen; Organochlorines; Marine mammals; Southern Ocean; Kerguelen Islands. |
Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/00111/22273/19948.pdf |
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Lahaye, V; Bustamante, Paco; Law, J.r; Learmonth, J.a; Santos, M.b.; Boon, J.p.; Rogan, E; Dabin, W; Addink, M.j.; Lopez, A; Zuur, A.f.; Pierce, G.j.; Caurant, Florence. |
Selected trace elements (Cd, Cu, Hg, Se, Zn) were measured in the kidneys and the liver of 104 harbour porpoises (Phocoena phocoena) stranded along the coasts of France, Galicia (Spain), Ireland, Scotland (UK), and the Netherlands. Generally, relatively low concentrations of toxic elements were encountered in the tissues of European porpoises, except for two individuals, which displayed high hepatic Hg concentrations. Also, elevated Cd levels obtained in Scottish porpoises could be related to their feeding preferences and this result suggests an increase of the proportion of cephalopods in their diet with latitude. Moreover, significant geographical differences were seen in hepatic Zn concentrations; the elevated Zn concentrations displayed by porpoises... |
Tipo: Text |
Palavras-chave: Tracers; Multivariate analysis; Diet; Age; Marine mammals; Zinc; Cadmium; Mercury; Heavy metals. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2920.pdf |
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Caurant, Florence; Amiard, Jean-claude; Amiard-triquet, Claude; Sauriau, Pierre-guy. |
Trace elements (As, Cd, Cu, Hg, Se and Zn) were determined in liver and kidney of pilot whales Globicephala melas Traill, 1809 collected from 7 schools caught at different seasons around the Faroe Islands. These and other biological data at our disposal enabled us to confirm and to define more accurately the relations shown previously between age, sex and trace element concentrations in marine mammals. The most striking features were: (1) the elevated levels of Cd and Hg in pilot whales compared to other marine mammals and to minimum adverse-effect levels established for humans; (2) the biocumulative behaviour of Cd and Hg; (3) the high correlations between Hg and Se, predominantly influenced by age; and (4) the high correlations between Cd and Zn, the... |
Tipo: Text |
Palavras-chave: Marine mammals; Heavy metals; Interactions. |
Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/00196/30766/29149.pdf |
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Leroy, Emmanuelle; Royer, Jean-yves; Alling, Abigail; Maslen, Ben; Rogers, Tracey L.. |
Blue whales were brought to the edge of extinction by commercial whaling in the twentieth century and their recovery rate in the Southern Hemisphere has been slow; they remain endangered. Blue whales, although the largest animals on Earth, are difficult to study in the Southern Hemisphere, thus their population structure, distribution and migration remain poorly known. Fortunately, blue whales produce powerful and stereotyped songs, which prove an effective clue for monitoring their different ‘acoustic populations.’ The DGD-Chagos song has been previously reported in the central Indian Ocean. A comparison of this song with the pygmy blue and Omura’s whale songs shows that the Chagos song are likely produced by a distinct previously unknown pygmy blue whale... |
Tipo: Text |
Palavras-chave: Animal migration; Biogeography; Marine biology; Marine mammals. |
Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00691/80280/83365.pdf |
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Lassalle, Geraldine; Gascuel, Didier; Le Loch, Francois; Lobry, Jeremy; Pierce, Graham John; Ridoux, Vincent; Santos, Maria Begona; Spitz, Jerome; Niquil, Nathalie. |
A number of marine mammal populations is currently threatened by their interactions with fisheries. The present study aimed to provide insights into the severity of potential impacts of operational and biological interactions between top predators and fisheries, in the Bay of Biscay region. Our approach was to modify an Ecopath with Ecosim (EwE) model describing the overall structure and function of the ecosystem by including landings and discards of exploited stocks and estimations of the bycatch of non-target compartments. Second, a set of ecological indices and a trophic level (TL)-based model (EcoTroph, ET) were derived from the EwE model. ET was used to simulate the effects of increasing fishing pressure on the ecosystem and, more particularly, on top... |
Tipo: Text |
Palavras-chave: Ecopath; Ecosystem modelling; EcoTroph; Fisheries impacts; Marine mammals; Trophic level. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00087/19855/17541.pdf |
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Morizur, Yvon; Gaudou, Olivier; Demaneche, Sebastien. |
During the years 2008 to 2013 several observations of catches were planned on board of set netters fishing in the bay of Biscay, in the English Channel, in the North sea and in the Mediterranean area (around Corsica). All the observations were done on nets without pingers and they were pooled to provide an average bycatch rate of marine mammals by fleet. Estimates of annual bycatch by using the fishing efforts of the year 2012 were provided by fleet. Harbour porpoise Phocoena phocoena was the most common bycatch in set nets. An average annual estimate of 600 harbour porpoises was obtained for the French fleet; other species recorded in set nets were mainly common dolphin Delphinus delphis, striped dolphin Stenella coeruleoalba and the two species of seals... |
Tipo: Text |
Palavras-chave: France; Bycatch; Marine mammals; Phocoena phocoena; Set nets; Trammel nets; Gill nets; EU regulation 812/2004. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00209/32016/30451.pdf |
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Marine-mammals data management team. |
The instrumented sea-mammals program is the global network of open-ocean in-situ observations, being implemented by an international partnership of researchers. Instrumented sea-mammals provide trajectories and vertical profiles of various physical, biogeochemical variables in different regions around the globe. The program’s objective is to build and maintain a multidisciplinary global network for a broad range of research and operational applications including biology, climate and ecosystem variability and forecasting and ocean state validation. Sea-mammals data are publicly available. More information about the project is available at: http://www.coriolis.eu.org/Observing-the-Ocean/Marine-Mammals The main purpose of this document is to specify the... |
Tipo: Text |
Palavras-chave: Marine mammals; Physical oceanography; In-situ marine data; Operational oceanography. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00255/36622/35194.pdf |
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Lurton, Xavier; Antoine, Loic. |
The use of acoustical systems in various human activities in the ocean (industry, defence, science) raises the issue of their impact upon marine mammals populations. Several serious accidents linked to the use of naval sonars led the military, industrial and scientific communities to investigate the potential dangers of their own activity. This report aims at identifying the risks for the cetaceans linked to the use of acoustic and seismic systems currently used for oceanographic science. The analysis proposed here stays within the frame of bibliography synthesis and elementary modelling, and brings no new scientific elements on the topic. An overview of the status of cetacean populations is given first, with a summary of the possible acoustical... |
Tipo: Text |
Palavras-chave: Seismics; Sonar; Acoustics; Oceanography; Acoustical methods; Auditory threshold; Stranding; Acoustical risks; Marine mammals. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/rapport-2390.pdf |
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Chiluiza, D.; Aguirre, W.; Félix, F.; Haase, B.. |
Between 1987 and 1995, 93 strandings of marine mammals were recorded along the ecuadorian continental coast, including one mass stranding of 56. The strandings involved 12 species of cetaceans (10 Odontoceti and 2 Mysticeti) and one species of pinniped. The Odontoceti were represented by: bottlenose dolphin Tursiops truncatus (n=30), sperm whale Physeter macrocephalus (n=25), Pacific spotted dolphin Stenella attenuata (n=7), striped dolphin Stenella coeruleoalba (n=2), false killer whale Pseudorca crassidens (n=2), Cuvier's beaked whale Ziphius cavirostris (n=2), short finned pilot whale Globicephala macrorhynchus (n=1), short-beaked common dolphin Delphinus delphis (n=3), Risso's dolphin Grampus griseus (n=1) and pygmy killer whale Feresa attenuata (n=1).... |
Tipo: Journal Contribution |
Palavras-chave: Marine mammals; Stranding; Coastal zone. |
Ano: 1998 |
URL: http://hdl.handle.net/1834/2264 |
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Registros recuperados: 75 | |
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