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Auteur PLANQUE, B.; FROMENTIN, J.-M.; CURY, P.; DRINKWATER, K.F.; JENNINGS, S.; PERRY, R.I.; KIFANI, S.
Titre How does fishing alter marine populations and ecosystems sensitivity to climate? Type Article scientifique
Année 2010 Publication (up) Journal of Marine Systems Revue Abrégée
Volume 79 Numéro 3-4 Pages 403-417
Mots-Clés Resilience; Marine ecosystems; Demography; Climate fishing interactions
Résumé Evidence has accumulated that climate variability influences the state and functioning of marine ecosystems. At the same time increasing pressure from exploitation and other human activities has been shown to impact exploited and non-exploited species and potentially modify ecosystem structure. There has been a tendency among marine scientists to pose the question as a dichotomy, i.e., whether (1) “natural” climate variability or (2) fishery exploitation bears the primary responsibility for population declines in fish populations and the associated ecosystem changes. However, effects of both climate and exploitation are probably substantially involved in most cases. More importantly, climate and exploitation interact in their effects, such that climate may cause failure in a fishery management scheme but that fishery exploitation may also disrupt the ability of a resource population to withstand, or adjust to, climate changes. Here, we review how exploitation, by altering the structure of populations and ecosystems, can modify their ability to respond to climate. The demographic effects of fishing (removal of large-old individuals) can have substantial consequences on the capacity of populations to buffer climate variability through various pathways (direct demographic effects, effects on migration, parental effects). In a similar way, selection of population sub-units within metapopulations may also lead to a reduction in the capacity of populations to withstand climate variability and change. At the ecosystem level, reduced complexity by elimination of species, such as might occur by fishing, may be destabilizing and could lead to reduced resilience to perturbations. Differential exploitation of marine resources could also promote increased turnover rates in marine ecosystems, which would exacerbate the effects of environmental changes. Overall (and despite the specificities of local situations) reduction in marine diversity at the individual, population and ecosystem levels will likely lead to a reduction in the resilience and an increase in the response of populations and ecosystems to future climate variability and change. Future management schemes will have to consider the structure and functioning of populations and ecosystems in a wider sense in order to maximise the ability of marine fauna to adapt to future climates. (C) 2009 Elsevier B.V. All rights reserved.
Adresse Univ E Anglia, Sch Environm Sci, Norwich NR4 7TJ, Norfolk, England.
Auteur institutionnel Thèse
Editeur Elsevier Lieu de Publication Éditeur
Langue Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0924-7963 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 7384 collection 1025
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Auteur FU, C.; LARGE, S.; KNIGHT, B.; RICHARDSON, A.J.; BUNDY, A.; REYGONDEAU, G.; BOLDT, J.; VAN DER MEEREN, G.I.; TORRES, M.A.; SOBRINO, I.; AUBER, A.; TRAVERS-TROLET, M.; PIRODDI, C.; DIALLO, I.; JOUFFRE, D.; MENDES, H.; BORGES, M.F.; LYNAM, C.P.; COLL, M.; SHANNON, L.J.; SHIN, Y.-J.
Titre Relationships among fisheries exploitation, environmental conditions, and ecological indicators across a series of marine ecosystems Type Article scientifique
Année 2015 Publication (up) Journal of Marine Systems Revue Abrégée
Volume 148 Numéro Pages 101-111
Mots-Clés ecological indicators; environmental conditions; fisheries exploitation; marine ecosystems; partial least squares path modeling
Résumé Understanding how external pressures impact ecosystem structure and functioning is essential for ecosystem-based approaches to fisheries management. We quantified the relative effects of fisheries exploitation and environmental conditions on ecological indicators derived from two different data sources, fisheries catch data (catch-based) and fisheries independent survey data (survey-based) for 12 marine ecosystems using a partial least squares path modeling approach (PLS-PM). We linked these ecological indicators to the total biomass of the ecosystem. Although the effects of exploitation and environmental conditions differed across the ecosystems, some general results can be drawn from the comparative approach. Interestingly, the PLS-PM analyses showed that survey-based indicators were less tightly associated with each other than the catch-based ones. The analyses also showed that the effects of environmental conditions on the ecological indicators were predominantly significant, and tended to be negative, suggesting that in the recent period, indicators accounted for changes in environmental conditions and the changes were more likely to be adverse. Total biomass was associated with fisheries exploitation and environmental conditions; however its association with the ecological indicators was weak across the ecosystems. Knowledge of the relative influence of exploitation and environmental pressures on the dynamics within exploited ecosystems will help us to move towards ecosystem-based approaches to fisheries management. PLS-PM proved to be a useful approach to quantify the relative effects of fisheries exploitation and environmental conditions and suggest it could be used more widely in fisheries oceanography.
Adresse University of Cape Town, Department of Biological Sciences, Ma-Re Marine Research Institute, Private Bag X3, Rondebosch, Cape Town 7701, South Africa
Auteur institutionnel Thèse
Editeur Elsevier Lieu de Publication Éditeur
Langue Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0924-7963 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 36155 collection 1229
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Auteur BANARU, D.; MELLON, C.; ROOS, D.; BIGOT, J.-L.; SOUPLET, A.; JADAUD, A.; Beaubrun, P.; FROMENTIN, J.-M.
Titre Trophic structure in the Gulf of Lions marine ecosystem (north-western Mediterranean Sea) and fishing impacts Type Article scientifique
Année 2013 Publication (up) Journal Of Marine Systems Revue Abrégée
Volume 111 Numéro Pages 45-68
Mots-Clés Gulf of Lions; Ecopath with Ecosim; Food web; Fishing impacts
Résumé The Gulf of Lions ecosystemwas described using the Ecopath mass-balancemodel to characterise its structure and functioning and to examine the effects of themultispecific fisheries operating in this area. The model is composed of 40 compartments, including 1 group of seabirds, 2 groups of etaceans, 18 groups of fish, 12 groups of invertebrates, 5 groups of primary producers, detritus and discards. Input datawere based on several recurrent scientific surveys, two alternative datasets for fishing data, stock assessment outputs, stomach content analyses and published information. Results showed that the functional groups were organised into five trophic levels with the highest one represented by dolphins, anglerfish, Atlantic bluefin tuna, European hake and European conger. European pilchard and European anchovy dominated in terms of fish biomass and catch. Other fish with high biomass such as Atlantic mackerel and blue whiting were highly important in the food web. Seabirds, dolphins and cuttlefish–squids represented keystone species. Important coupled pelagic–demersal–benthic interactions were described. The 7 different fisheries analysed were operating at mean trophic levels situated between 2.6 for small artisanal boats, and 4.1 for purse seines (>24 m) targeting large pelagic fish, indicating an intensively exploited ecosystem. Large trawlers (24–40 m) had the highest impact on most of the groups considered; while purse seines (12–24 m) targeting small pelagic fish had the lowest impact. Preliminary results highlighted the importance of data sources for further ecosystem and fisheries analyses and management scenarios.
Adresse Univ Montpellier, Ecole Prat Hautes Etud, Montpellier, France.
Auteur institutionnel Thèse
Editeur Elsevier Science Bv Lieu de Publication Éditeur
Langue Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0924-7963 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ 22758 collection 994
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