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Registros recuperados: 298 | |
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Carpentier, Andre; Coppin, Franck. |
lfremer carries out a yearly bottom trawl survey named Channel Ground Fish Survey (CGFS) in order to collect essential biological data on major exploited fish species in the Eastern Channel. These data are also provided to feed the indispensable historie series to the yearly assessment of resources. This report presents results of the CGFS surveys for 1997 and 1998, under two aspects: a multispecific approach of the biological assemblages and integrating an interannual analysis, then a monospecific analysis of 7 species of commercial interest, as whiting, pout, cod, red gurnard, plaice, black bream, red mullet. OCR NOT CONTROLLED |
Tipo: Text |
Palavras-chave: Aspitrigla cuculus; Grondin rouge; Gadus morhua; Morue; Trisopterus luscus; Tacaud; Merlangius merlangus; Merlan; Multi espèces; Cartographie; Répartition; Abondance; Distribution; Manche orientale; Chalutage; Campagne; Plaice; Aspilngla cuculus; Red gurnard; Gadus morhua; Cod; Trisopterus luscus; Pout; Merlangius merlangus; Whiting; Multispecies; Cartography; Abundance; Distribution; Eastern Channel; Trawling; Survey. |
Ano: 2000 |
URL: https://archimer.ifremer.fr/doc/2000/rapport-3606.pdf |
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Lazard, Coline; Verin, Yves; Auber, Arnaud. |
In 2021, the French NS-IBTS Q1 survey was conducted as part of the International Bottom Trawl Survey program carried out by main countries bordering the North Sea in order to assess abundance and stocks distribution, independently of commercial fisheries data. The first target of the NS-IBTS Q1 survey is to provide a diagnosis on the main commercial fish species by estimating their abundance per age. A standardized protocol is rigorously applied by all participants. The R/V Thalassa sampled the eastern part of the Channel and southern North Sea (until 56° N) from 19th January to 9th February 2021. During daily time, 56 hauls, lasting 30 minutes, have been carried out with a GOV bottom trawl. A total of 82 fish species have been collected, determined and... |
Tipo: Text |
Palavras-chave: North sea; GOV; Beam trawl; MIK; Abundance; Stock assessment. |
Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00691/80333/83418.pdf |
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Saulia, Emmrick; Benavides, Mar; Henke, Britt; Turk-kubo, Kendra; Cooperguard, Haley; Grosso, Olivier; Desnues, Anne; Rodier, Martine; Dupouy, Cécile; Riemann, Lasse; Bonnet, Sophie. |
Coastal and open ocean regions of the Western Tropical South Pacific ocean have been identified as a hotspot of N2 fixation. However, the environmental factors driving the temporal variability of abundance, composition, and activity of diazotrophs are still poorly understood, especially during the winter season. To address this, we quantified N2 fixation rates and the abundance of seven diazotroph phylotypes (UCYN-A1 symbiosis, UCYN-B, UCYN-C, Trichodesmium, Het-1, Het-2, and Het-3) on a monthly basis during two full years (2012 to 2014) at four stations along a coast to open ocean transect in the New Caledonian lagoon. The total nifH gene concentration (sum of all nifH gene copies) clearly decreased from the barrier reef to the shore. Apart from UCYN-B,... |
Tipo: Text |
Palavras-chave: N-2 fixation; Diazotrophs; NifH; Abundance; New Caledonia. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00658/77027/78307.pdf |
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Chen, C; Pierce, G; Wang, J; Robin, J; Poulard, Jean-charles; Pereira, J; Zuur, A; Boyle, P; Bailey, N; Beare, D; Jereb, P; Ragonese, S; Mannini, A; Orsi-relini, L. |
Since the early 1990s, Loligoforbesi has apparently disappeared from much of the southern part of its former range, with catches off the Iberian Peninsula, for example, declining dramatically during the 1990s. The present paper assembles data from fishery and research cruise databases to examine the evidence for a shift in distribution, examine the relationship between abundance of this species and that of the partially sympatric Loligo vulgaris, and identify possible environmental correlates. Time-series of abundance of L. forbesi and L. vulgaris were assembled using fishery and survey data from Scotland, France, and Portugal. Based on availability of data and timing of the main fishery, data for autumn (October-December) were selected. Nine squid series... |
Tipo: Text |
Palavras-chave: North Atlantic Oscillation NAO; Dynamic factor analysis; Common trends; Abundance; Squid fishery; Loligo. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1539.pdf |
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Trenkel, Verena; Pinnegar, John; Rochet, Marie-joelle; Rackham, Brian. |
Choice of sampling method and survey period can have an important impact on the perception of the structure and dynamics of an ecological community. For the Celtic Sea fish assemblage we compared data obtained by three different trawl surveys: an autumn groundfish survey with a GOV trawl, and a spring and an autumn groundfish survey, both carried out with a Portuguese high-headline trawl. Time-series of abundance estimates were not consistent among surveys for all species and were generally very noisy. An analysis of variance components showed that the sampling method contributed more to the variance in abundance estimates compared to survey period, interannual variability, or even sampling variance. Overall community assessments based on indicators such... |
Tipo: Text |
Palavras-chave: Trawl; Survey; Species diversity; Size spectrum; Celtic Sea; Abundance. |
Ano: 2004 |
URL: https://archimer.ifremer.fr/doc/2004/publication-899.pdf |
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Sinovcic, G; Alegriahernandez, V. |
The catch per unit effort of the sardine, Sardina pilchardus (Walbaum, 1792), on the eastern Adriatic fishing grounds has greatly increased in recent years, notably during the past decade. We compared the relationship between annual mean total length and catch per unit effort (CPUE), as an index of population abundance. Decrease in fish size indicated the occurrence of a strong year class and led to an increase abundance in subsequent years. Long-term variations in catch per unit effort for 1963-1988 in relation to primary production, temperature, salinity and oxygen were analysed, with reference to the sardine, in the principal fishing grounds of the eastern part of the Adriatic. This correlation analysis confirmed the impact of these factors on... |
Tipo: Text |
Palavras-chave: Sardine; Adriatic; Abundance. |
Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00093/20453/18125.pdf |
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Ravier, Christelle; Fromentin, Jean-marc. |
More than one hundred long-term time-series of bluefin tuna catches from the ancestral Mediterranean and Atlantic trap fisheries are used to (1) estimate historical range of BFT yields in the Mediterranean and adjacent Atlantic and (2) investigate spatial and temporal patterns of fluctuations in trap catches. Mean historical catches were around 110 000 tunas/year (± 50 000), i.e. 15 000 tons/year (∈[7 000;25 000]). Fluctuations in trap catches are of large magnitude, periods of high abundance being up to seven times higher than those of low abundance. More interesting was the occurrence of 100-year-long periodic fluctuations as well as 20-year cycles. These medium- to long-term fluctuations, representing more than 50% of the total variability in the... |
Tipo: Text |
Palavras-chave: Thunnus thynnus; Time series analyses; Abundance; Population dynamics; Long-term changes; Trapfishing. |
Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/00194/30497/28906.pdf |
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Gueroun, Sonai M; Molinero, Juan-carlos; Piraino, Stefano; Dali Yahia, Mohamed Nejib. |
Understanding the life cycle strategies and predatory impact of alien jellyfish species is critical to mitigate the impact that these organisms may have on local populations, biodiversity, and ultimately on the functioning of food webs. In the Mediterranean Sea, little is known about the dynamics of alien jellyfish, despite this biodiversity hotspot being one of the most threatened areas by increasing numbers of alien jellyfish. Here, we investigated the population dynamics and predatory impact of a non-indigenous scyphomedusa, Aurelia solida Browne 1905, in the Bizerte Lagoon, Tunisia. The study was based on bimonthly surveys performed over two consecutive years, from November 2012 to August 2014. Field observations showed that the planktonic phase of A.... |
Tipo: Text |
Palavras-chave: Scyphomedusae; Abundance; Predation; Mesozooplankton; SW Mediterranean. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00624/73577/72966.pdf |
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Leaute, Jean-pierre; Aubert, Fabien; Lepareur, Fanny; Coupeau, Yann; Boiron-leroy, Anne. |
A large number of studies on common sole have already been done for years by many research laboratories. This study sought to make a focus on a major nursery on the Atlantic coast, the Pertuis charentais, through the results of eight annual surveys (2005-2012) in late summer (SOLe PERtuis) targeting sole juveniles with a small beam trawl until subtidal zone (<1.50 m). Some of the results obtained in this report confirm previous studies, such as, among others, that more than 80% YOY (G0) occupy muddy or sandy mud bottom at a depth less than 5 m, or that there is a relative correlation between large rainfall in the spring, river flows and abundance of G0 in nursery. However in the Pertuis Breton this correlation is little expressed by an extension of... |
Tipo: Text |
Palavras-chave: Sole commune; Solea solea; Chalut à perche; Abondance; Pertuis charentais; Common sole; Solea solea; Beam trawl; Abundance; Pertuis charentais. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00422/53357/54196.pdf |
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Lazard, Coline; Verin, Yves; Auber, Arnaud. |
IBTS surveys (International Bottom Trawl Survey) are carried out within an international framework. Main countries bordering the North Sea participate to it according to the European Community regulations (EC N°1543/2000 and N° 1639/2001) which specify that countries from E.U. have to carry out surveys at sea in order to evaluate abundance and stocks distribution, independently of commercial fisheries data. The first target of the IBTS survey is to have a diagnosis on the main commercial fish stock and to calculate abundances index by age for these species. This survey started in the years 70’s and gradually standardised. Since the years 80’s, a common protocol is implemented and used by all participants. The same fishing gear and the same working methods... |
Tipo: Text |
Palavras-chave: North sea; GOV; Beam trawl; MIK; Abundance; Stock assessment. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00655/76740/77891.pdf |
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Samb, Birame; Petitgas, Pierre. |
This study presents an application of the geostatistical one-dimensional (1D) transitive method for estimating the precision of acoustic pelagic abundance estimates in Senegal. In applying the method, the major problem encountered was how to take into account the temporal variability in the computation of the estimation variance. In acoustic surveys, echointegration is performed continuously along the ship's sailing track. For a survey design made of parallel transects, each transect can thus be considered as a sampling unit. By summing the density values along the transects to obtain biomass values per transect, the 2D estimation is simply reduced to a 1D estimation procedure. If the transects are equidistant, the geostatistical transitive method applied... |
Tipo: Text |
Palavras-chave: Céostatistique; Variance; Acoustique; Abondance; Geostatistics; Variance; Acoustics; Abundance. |
Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00188/29883/28348.pdf |
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Jean, Claire; Ciccione, Stephane; Ballorain, Katia; Georges, Jean-yves; Bourjea, Jerome. |
Reunion Island in the south-west Indian Ocean once had significant nesting populations of marine turtles but they declined rapidly after human colonization. In 1996, after regular sightings of turtles offshore, an aerial survey programme was initiated to monitor the occurrence of marine turtles and their distribution along the west coast of the island Between 1998 and 2008, along a 30-km coastline transect between Saint Leu and Saint Paul, a total of 1,845 marine turtle sightings were recorded during 146 flights with an ultralight aircraft The mean number of turtle sightings per survey increased significantly between 1998 and 2008, and a variety of sizes were recorded throughout the year Marine turtles were found over coral reef zones and on the outer reef... |
Tipo: Text |
Palavras-chave: Abundance; Aerial survey; Conservation; Indian Ocean; Marine turtles; Reunion Island. |
Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00005/11588/9280.pdf |
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Carpentier, André; Coppin, Franck. |
Ifremer carries out a yearly bottom trawl survey named Channel Ground Fish Survey (CGFS) in order to collect essential biological data on major exploited fish species in the Eastern Channel. These data are also provided to feed the indispensable historic series to the yearly assessment of resources. This report presents results of the CGFS surveys for 1997 and 1998, under two aspects : a multispecific approach of the biological assemblages and integrating an interannual analysis, then a monospecific analysis of 7 species of commercial interest, as whiting, pout, cod, red gurnard, plaice, black bream, red mullet. |
Tipo: Text |
Palavras-chave: Campagne; Chalutage; Manche orientale; Distribution; Abondance; Répartition; Cartographie; Multiespèces; Merlan; Merlangius merlangus; Tacaud; Trisopterus luscus; Morue; Gadus morhua; Grondin rouge; Aspitrigla cuculus; Plie; Pleuronectes platessa; Griset; Spondyliosoma cantharus; Survey; Trawling; Eastern Channel; Distribution; Abundance; Cartography; Multi-species; Whiting; Merlangius merlangus; Pout; Trisopterus luscus; Cod; Gadus morhua; Red gurnard; Aspitrigla cuculus; Plaice; Pleuronectesplatessa; Black bream; Spondyliosoma cantharus; Red mullet. |
Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00306/41762/40975.pdf |
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Trenkel, Verena; Mazauric, Valerie; Berger, Laurent. |
Recently, Simrad in collaboration with Ifremer developed a calibrated, multibeam, vertical echosounder (ME70) for fisheries research. We describe its capabilities and technical limitations. The ME70 has up to 45 beams with distinct frequencies in the range 70120 kHz, spanning at most 150 degrees. All beams are stabilized in vessel roll and pitch. It has reduced side-lobe levels, up to -70 dB (two-way) instead of the -2S dB (one-way) of conventional systems. We outline research areas for which the ME70 might provide new types of information and hence lead to novel insights. We illustrate the potential contributions with datasets collected in the English Channel and on the continental-shelf break of the Bay of Biscay. Finally, future research and... |
Tipo: Text |
Palavras-chave: Three dimensional; Behaviour; Acoustics; Abundance. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4117.pdf |
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Petitgas, Pierre; Goarant, Anne; Masse, Jacques; Bourriau, Paul. |
Petitgas, P., Goarant, A., Masse, J., and Bourriau, P. 2009. Combining acoustic and CUFES data for the quality control of fish-stock survey estimates. - ICES Journal of Marine Science, 66: 1384-1390. |
Tipo: Text |
Palavras-chave: CUFES; Biscay; Bias; Anchovy; Acoustics; Abundance. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6566.pdf |
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Registros recuperados: 298 | |
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