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Auteur Batsleer, J.; Marchal, P.; Vaz, S.; Vermard, V.; Rijnsdorp, A.D.; Poos, J.J. doi  openurl
  Titre Exploring habitat credits to manage the benthic impact in a mixed fishery Type Article scientifique
  Année 2018 Publication Revue Abrégée Mar. Ecol.-Prog. Ser.  
  Volume 586 Numéro Pages 167-179  
  Mots-Clés growth; sea; reserves; marine protected areas; juvenile; Plaice; Eastern English Channel; Fleet dynamics; vms data; fishing disturbance; central english-channel; Cod; costs; Dynamic state variable modelling; georges bank; Mixed fisheries; tac; Total allowable catch  
  Résumé The performance of a combined catch quota and habitat credit system was explored to manage the sustainable exploitation of a mix of demersal fish species and reduce the benthic impacts of bottom trawl fisheries using a dynamic state variable model approach. The model was parameterised for the Eastern English Channel demersal mixed fishery using otter trawls or dredges. Target species differed in their association with habitat types. Restricting catch quota for plaice and cod had a limited effect on benthic impact, except when reduced to very low values, forcing the vessels to stay in port. Quota management had a minimal influence on fishing behaviour and hence resulted in a minimal reduction of benthic impact. Habitat credits may reduce the benthic impacts of the trawl fisheries at a minimal loss of landings and revenue, as vessels are still able to reallocate their effort to less vulnerable fishing grounds, while allowing the fishery to catch their catch quota and maintain their revenue. Only if they are reduced to extremely low levels can habitat credits potentially constrain fishing activities to levels that prevent the fisheries from using up the catch quota for the target species.  
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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 0171-8630 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2283  
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Auteur Bauer, R.K.; Stepputtis, D.; Gräwe, U.; Zimmermann, C.; Hammer, C. url  doi
openurl 
  Titre Wind-induced variability in coastal larval retention areas: a case study on Western Baltic spring-spawning herring Type Article scientifique
  Année 2013 Publication Revue Abrégée Fisheries Oceanography  
  Volume Numéro Pages  
  Mots-Clés atmospheric forcing; Baltic Sea; biophysical modelling; Greifswalder Bodden; herring; larval retention; recruitment; spring spawners  
  Résumé The investigation of larval dispersal and retention, their variability and dependence on wind conditions, has become a major topic in fisheries research owing to potential effects on stock recruitment and stock structuring. The present study quantifies the wind-induced variability of larval retention of herring in a highly productive coastal lagoon of the Western Baltic Sea. This lagoon, the Greifswalder Bodden, represents the main spawning area of Western Baltic Spring-Spawning Herring, a stock that has recently undergone a continuous decline in recruitment. The study tests whether this decline was related to changes in larval retention, more precisely to changes in wind conditions, the main forcing of the lagoon's circulation. To answer this, a model approach was applied. Larvae were tracked as Lagrangian drifters under constant and variable wind conditions, examining the main drift patterns and reconstructing the incidents during the period of recruitment decline. For the latter, weekly cohorts of virtual larvae were released in the lagoon over the entire spawning period (April–June; \textgreater16 weeks). The fraction of retained larvae per cohort was related to observed larval abundances. On this basis, a new retention index was defined to evaluate the annual larval retention. The results presented cannot explain the observed recruitment decline but characterize the lagoon as an important larval retention area by virtue of unsteady wind conditions that prevent a steady outflow of larvae.  
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  Volume de collection Numéro de collection Edition  
  ISSN 1365-2419 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 255  
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Auteur Benedetti, F.; Ayata, S.-D.; Irisson, J.-O.; Adloff, F.; Guilhaumon, F. doi  openurl
  Titre Climate change may have minor impact on zooplankton functional diversity in the Mediterranean Sea Type Article scientifique
  Année 2019 Publication Revue Abrégée Divers. Distrib.  
  Volume 25 Numéro 4 Pages 568-581  
  Mots-Clés biogeography; calanus-helgolandicus; climate change; communities; conservation; fish assemblages; framework; functional diversity; future; marine biodiversity; Mediterranean Sea; niche modelling; null model; ocean; trait; zooplankton  
  Résumé Aim To assess the impact of climate change on the functional diversity of marine zooplankton communities. Location The Mediterranean Sea. Methods We used the functional traits and geographic distributions of 106 copepod species to estimate the zooplankton functional diversity of Mediterranean surface assemblages for the 1965-1994 and 2069-2098 periods. Multiple environmental niche models were trained at the global scale to project the species habitat suitability in the Mediterranean Sea and assess their sensitivity to climate change predicted by several scenarios. Simultaneously, the species traits were used to compute a functional dendrogram from which we identified seven functional groups and estimated functional diversity through Faith's index. We compared the measured functional diversity to the one originated from null models to test if changes in functional diversity were solely driven by changes in species richness. Results All but three of the 106 species presented range contractions of varying intensity. A relatively low decrease of species richness (-7.42 on average) is predicted for 97% of the basin, with higher losses in the eastern regions. Relative sensitivity to climate change is not clustered in functional space and does not significantly vary across the seven copepod functional groups defined. Changes in functional diversity follow the same pattern and are not different from those that can be expected from changes in richness alone. Main conclusions Climate change is not expected to alter copepod functional traits distribution in the Mediterranean Sea, as the most and the least sensitive species are functionally redundant. Such redundancy should buffer the loss of ecosystem functions in Mediterranean zooplankton assemblages induced by climate change. Because the most negatively impacted species are affiliated to temperate regimes and share Atlantic biogeographic origins, our results are in line with the hypothesis of increasingly more tropical Mediterranean communities.  
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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 1366-9516 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2582  
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Auteur Chaboud, C.; Vendeville, P. url  doi
openurl 
  Titre Evaluation of selectivity and bycatch mitigation measures using bioeconomic modelling. The cases of Madagascar and French Guiana shrimp fisheries Type Article scientifique
  Année 2011 Publication Revue Abrégée Aquatic Living Resources  
  Volume 24 Numéro 2 Pages 137-148  
  Mots-Clés Bioeconomics; Bycatch; mitigation; modelling; selectivity; Shrimp fisheries  
  Résumé Tropical shrimp fisheries are characterized by various interactions with their natural environment and with other fisheries. These latter interactions can be explained by the high quantity of bycatch taken by industrial trawler fleets, which has a significant impact on fish populations associated with shrimps and thus also on finfish fisheries. Bycatch also includes emblematic species, which are subject to strict conservation measures decided by the international community. It seems important to identify and assess the biological and economic consequences of different mitigation measures (increase of mesh size, turtle excluder devices and bycatch reducing devices). This communication is based on case studies undertaken on the Indian white prawn (Fenneropenaeus indicus) and speckled shrimp (Metapenaeus monoceros) fisheries in Madagascar and on the brown shrimp (Farfantepenaeus subtilis) and pink spotted shrimp (Farfantepenaeus brasiliensis) fishery in French Guiana. A review of the impacts of these fisheries on resources and ecosystems is made and some results of experiments on mitigation devices given. Finally, the results of simulations obtained using a multi-species, multi-fleet, age-structured bioeconomic model, including modifications of catchability and costs related to the adoption of these devices, is presented and discussed.  
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  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0990-7440 ISBN Médium  
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  Numéro d'Appel LL @ pixluser @ collection 128  
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Auteur Coll, M.; Akoglu, E.; Arreguín-Sánchez, F.; Fulton, E.A.; Gascuel, D.; Heymans, J.J.; Libralato, S.; Mackinson, S.; Palomera, I.; Piroddi, C.; Shannon, L.J.; Steenbeek, J.; Villasante, S.; Christensen, V. url  doi
openurl 
  Titre Modelling dynamic ecosystems: venturing beyond boundaries with the Ecopath approach Type Article scientifique
  Année 2015 Publication Revue Abrégée Rev Fish Biol Fisheries  
  Volume 25 Numéro 2 Pages 413-424  
  Mots-Clés conservation; Cumulative impacts; Ecopath with Ecosim; ecospace; ecosystem-based management; ecosystem modelling; End-to-end modelling; Environmental impact assessment; fishing impacts; Freshwater & Marine Ecology; Zoology  
  Résumé Thirty years of progress using the Ecopath with Ecosim (EwE) approach in different fields such as ecosystem impacts of fishing and climate change, emergent ecosystem dynamics, ecosystem-based management, and marine conservation and spatial planning were showcased November 2014 at the conference “Ecopath 30 years-modelling dynamic ecosystems: beyond boundaries with EwE”. Exciting new developments include temporal-spatial and end-to-end modelling, as well as novel applications to environmental impact analyses, in both aquatic and terrestrial domains. A wide range of plug-ins have been added to extend the diagnostic capabilities of EwE, and the scientific community is applying EwE to a diversified range of topics besides fishing impact assessments, such as the development of scientific advice for management, the analysis of conservation issues, and the evaluation of cumulative impacts of environmental and human activities in marine food webs (including habitat modification and the invasion of alien species). Especially promising is the new potential to include the EwE model in integrated assessments with other models such as those related to climate change research. However, there are still many challenges, including the communication of scientific results in management procedures. In addition, other important scientific issues are how to improve model result validation and perform model quality control. During the conference, the Ecopath International Research and Development Consortium was presented as a way for the EwE user community to become involved in the long-term sustainability of the EwE approach. Overall, exciting times are facing the ecosystem modelling scientific community, and as illustrated by the conference: synergistic cooperation is the future path for the EwE approach.  
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  ISSN 0960-3166, 1573-5184 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1249  
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