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Auteur Foveau, A.; Vaz, S.; Desroy, N.; Kostylev, V.E. doi  openurl
  Titre Process-driven and biological characterisation and mapping of seabed habitats sensitive to trawling Type Article scientifique
  Année 2017 Publication Revue Abrégée PLoS One  
  Volume 12 Numéro 10 Pages (down) e0184486  
  Mots-Clés beam trawl; benthic communities; british-isles; continental-shelf; english-channel; fishing disturbance; impact; north-sea; scotian shelf; taxonomic sufficiency  
  Résumé The increase of anthropogenic pressures on the marine environment together with the necessity of a sustainable management of marine living resources have underlined the need to map and model coastal environments, particularly for the purposes of spatial planning and for the implementation of integrated ecosystem-based management approach. The present study compares outputs of a process-driven benthic habitat sensitivity (PDS) model to the structure, composition and distribution of benthic invertebrates in the Eastern English Channel and southern part of the North Sea. Trawl disturbance indicators (TDI) computed from species biological traits and benthic community composition were produced from samples collected with a bottom trawl. The TDI was found to be highly correlated to the PDS further validating the latter's purpose to identify natural process-driven pattern of sensitivity. PDS was found to reflect an environmental potential that may no longer be fully observable in the field and difference with in situ biological observations could be partially explained by the spatial distribution of fishery pressure on the seafloor. The management implication of these findings are discussed and we suggest that, used in conjunction with TDI approaches, PDS may help monitor management effort by evaluating the difference between the current state and the presumed optimal environmental status of marine benthic habitats.  
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  ISSN 1932-6203 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2202  
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Auteur Freon, P.; Avadi, A.; Chavez, R.A.V.; Ahon, F.I. url  doi
openurl 
  Titre Life cycle assessment of the Peruvian industrial anchoveta fleet : boundary setting in life cycle inventory analyses of complex and plural means of production Type Article scientifique
  Année 2014 Publication Revue Abrégée International Journal of Life Cycle Assessment  
  Volume 19 Numéro 5 Pages (down) 1068-1086  
  Mots-Clés Attributional LCA; Complex production system; Environmental impacts; Fishing vessel; Fuel use; Life cycle inventory  
  Résumé This work has two major objectives: (1) to perform an attributional life cycle assessment (LCA) of a complex mean of production, the main Peruvian fishery targeting anchoveta (anchovy) and (2) to assess common assumptions regarding the exclusion of items from the life cycle inventory (LCI). Data were compiled for 136 vessels of the 661 units in the fleet. The functional unit was 1 t of fresh fish delivered by a steel vessel. Our approach consisted of four steps: (1) a stratified sampling scheme based on a typology of the fleet, (2) a large and very detailed inventory on small representative samples with very limited exclusion based on conventional LCI approaches, (3) an impact assessment on this detailed LCI, followed by a boundary-refining process consisting of retention of items that contributed to the first 95 % of total impacts and (4) increasing the initial sample with a limited number of items, according to the results of (3). The life cycle impact assessment (LCIA) method mostly used was ReCiPe v1.07 associated to the ecoinvent database. Some items that are usually ignored in an LCI's means of production have a significant impact. The use phase is the most important in terms of impacts (66 %), and within that phase, fuel consumption is the leading inventory item contributing to impacts (99 %). Provision of metals (with special attention to electric wiring which is often overlooked) during construction and maintenance, and of nylon for fishing nets, follows. The anchoveta fishery is shown to display the lowest fuel use intensity worldwide. Boundary setting is crucial to avoid underestimation of environmental impacts of complex means of production. The construction, maintenance and EOL stages of the life cycle of fishing vessels have here a substantial environmental impact. Recommendations can be made to decrease the environmental impact of the fleet.  
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  ISSN 0948-3349 ISBN Médium  
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Auteur Joo, R.; Bertrand, S.; Chaigneau, A.; Niquen, M. url  doi
openurl 
  Titre Optimization of an artificial neural network for identifying fishing set positions from VMS data : an example from the Peruvian anchovy purse seine fishery Type Article scientifique
  Année 2011 Publication Revue Abrégée Ecological Modelling  
  Volume 222 Numéro Pages (down) 1048-1059  
  Mots-Clés analysis; anchovy; Artificial; fishery; Fishing; locations; Monitoring; networks; neural; purse; seine; Sensitivity; set; System; Vessel  
  Résumé The spatial behavior of numerous fishing fleets is nowadays well documented thanks to satellite Vessel Monitoring Systems (VMS). Vessel positions are recorded on a frequent and regular basis which opens promising perspectives for improving fishing effort estimation and management. However, no specific information is provided on whether the vessel is fishing or not. To answer that question, existing works on VMS data usually apply simple criteria (e.g. threshold on speed). Those simple criteria generally focus in detecting true positives (a true fishing set detected as a fishing set); conversely, estimation errors are given no attention. For our case study, the Peruvian anchovy fishery, those criteria overestimate the total number of fishing sets by 182%. To overcome this problem an artificial neural network (ANN) approach is presented here. In order to set both the optimal parameterization and use “rules” for this ANN, we perform an extensive sensitivity analysis on the optimization of (1) the internal structure and training algorithm of the ANN and (2) the “rules” used for choosing both the relative size and the composition of the databases (DBs) used for training and inferring with the ANN. The “optimized” ANN greatly improves the estimates of the number and location of fishing events. For our case study, ANN reduces the total estimation error on the number of fishing sets to 1% (in average) and obtains 76% of true positives. This spatially explicit information on effort, provided with error estimation, should greatly reduce misleading interpretations of catch per unit effort and thus significantly improve the adaptive management of fisheries. While fitted on Peruvian anchovy fishery data, this type of neural network approach has wider potential and could be implemented in any fishery relying on both VMS and at-sea observer data. In order to increase the accuracy of the ANN results, we also suggest some criteria for improving sampling design by at-sea observers and VMS data.  
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  Numéro d'Appel LL @ pixluser @ collection 147  
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Auteur Helias, A.; Langlois, J.; Freon, P. doi  openurl
  Titre Fisheries in life cycle assessment: Operational factors for biotic resources depletion Type Article scientifique
  Année 2018 Publication Revue Abrégée Fish. Fish.  
  Volume 19 Numéro 6 Pages (down) 951-963  
  Mots-Clés catch; catch series; characterization factor; fishing impact; global fisheries; impact assessment; impact assessment method; lca; surplus production model  
  Résumé Life cycle assessment (LCA) is the normed and international framework for assessing the environmental impacts of most human activities. LCA is commonly used to assess various aspects of fisheries but is only at the onset for estimating impacts of fish removal. This study proposes original characterization factors (CFs) to quantify impacts on biotic resources using the mass of fish caught. This mid-point assessment occurs in impact pathways leading to natural resources, one of the three areas of protection in LCA, and thus fisheries can be compared according to the depleted stock fraction. CFs are defined by the marginal approach applied to the Schaefer model, representing the dynamics of the stocks. They combine catches, current biomass and maximum intrinsic growth rates, determined from the application of the CMSY algorithm (Froese etal. (2017), Fish Fish, 18, 506) with FAO and FishBase data. A multistock CF is also proposed and used for multispecies-stocks. CFs for the 4,993 stocks defined from global FAO areas are obtained and sorted according to the robustness of the model hypotheses. CF values among stocks generally tend to decrease when fish catches increase because high catches are generally associated with abundant stocks. Multispecies-stocks CFs for the northeast Atlantic Ocean are compared to ICES-based CFs and are reliable for the main fished stocks. With this simple and generic structure, this operational fish resource depletion potential could be extended to other biotic resources.  
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  ISSN 1467-2960 ISBN Médium  
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Auteur Coll, M.; Shannon, L.J.; Kleisner, K.M.; Juan-Jordá, M.J.; Bundy, A.; Akoglu, A.G.; Banaru, D.; Boldt, J.L.; Borges, M.F.; Cook, A.; Diallo, I.; Fu, C.; Fox, C.; Gascuel, D.; Gurney, L.J.; Hattab, T.; Heymans, J.J.; Jouffre, D.; Knight, B.R.; Kucukavsar, S.; Large, S.I.; Lynam, C.; Machias, A.; Marshall, K.N.; Masski, H.; Ojaveer, H.; Piroddi, C.; Tam, J.; Thiao, D.; Thiaw, M.; Torres, M.A.; Travers-Trolet, M.; Tsagarakis, K.; Tuck, I.; van der Meeren, G.I.; Yemane, D.; Zador, S.G.; Shin, Y.-J. url  doi
openurl 
  Titre Ecological indicators to capture the effects of fishing on biodiversity and conservation status of marine ecosystems Type Article scientifique
  Année 2016 Publication Revue Abrégée Ecological Indicators  
  Volume 60 Numéro Pages (down) 947-962  
  Mots-Clés Biodiversity; Conservation; Ecological indicators; Fishing impacts; Marine ecosystems; Redundancy; States; Trends  
  Résumé IndiSeas (“Indicators for the Seas”) is a collaborative international working group that was established in 2005 to evaluate the status of exploited marine ecosystems using a suite of indicators in a comparative framework. An initial shortlist of seven ecological indicators was selected to quantify the effects of fishing on the broader ecosystem using several criteria (i.e., ecological meaning, sensitivity to fishing, data availability, management objectives and public awareness). The suite comprised: (i) the inverse coefficient of variation of total biomass of surveyed species, (ii) mean fish length in the surveyed community, (iii) mean maximum life span of surveyed fish species, (iv) proportion of predatory fish in the surveyed community, (v) proportion of under and moderately exploited stocks, (vi) total biomass of surveyed species, and (vii) mean trophic level of the landed catch. In line with the Nagoya Strategic Plan of the Convention on Biological Diversity (2011–2020), we extended this suite to emphasize the broader biodiversity and conservation risks in exploited marine ecosystems. We selected a subset of indicators from a list of empirically based candidate biodiversity indicators initially established based on ecological significance to complement the original IndiSeas indicators. The additional selected indicators were: (viii) mean intrinsic vulnerability index of the fish landed catch, (ix) proportion of non-declining exploited species in the surveyed community, (x) catch-based marine trophic index, and (xi) mean trophic level of the surveyed community. Despite the lack of data in some ecosystems, we also selected (xii) mean trophic level of the modelled community, and (xiii) proportion of discards in the fishery as extra indicators. These additional indicators were examined, along with the initial set of IndiSeas ecological indicators, to evaluate whether adding new biodiversity indicators provided useful additional information to refine our understanding of the status evaluation of 29 exploited marine ecosystems. We used state and trend analyses, and we performed correlation, redundancy and multivariate tests. Existing developments in ecosystem-based fisheries management have largely focused on exploited species. Our study, using mostly fisheries independent survey-based indicators, highlights that biodiversity and conservation-based indicators are complementary to ecological indicators of fishing pressure. Thus, they should be used to provide additional information to evaluate the overall impact of fishing on exploited marine ecosystems.  
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