|   | 
Détails
   web
Enregistrements
Auteur Batsleer, J.; Marchal, P.; Vaz, S.; Vermard, V.; Rijnsdorp, A.D.; Poos, J.J.
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.
Adresse
Auteur institutionnel Thèse
Editeur Lieu de Publication Éditeur
Langue English Langue du Résumé Titre Original (up)
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0171-8630 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ alain.herve @ collection 2283
Lien permanent pour cet enregistrement
 

 
Auteur Jimenez, H.; Dumas, P.; Mouillot, D.; Bigot, L.; Ferraris, J.
Titre Harvesting effects on functional structure and composition of tropical invertebrate assemblages Type Article scientifique
Année 2016 Publication Revue Abrégée ICES J. Mar. Sci.
Volume 73 Numéro 2 Pages 420-428
Mots-Clés Bta; marine protected areas; shellfishing; species composition; tropical benthos
Résumé Anthropogenic disturbances affect ecosystem structure and functioning. The quantification of their impacts on highly diverse and structurally complex ecosystems, such as coral reefs, is challenging. These communities are facing rising fishing pressure, particularly on Pacific Islands such as New Caledonia. The main objective was to quantify harvesting effects on invertebrate assemblages across two contrasting habitats (soft- and hard-bottom), by comparing communities in marine protected areas (MPAs) with non-MPAs using 10 biological and ecological traits. Patterns of trait composition were compared with those of species composition by non-metric multidimensional scaling and permutational analysis of variance analyses. Traits most responsible for differences between MPAs and non-MPAs were determined using SIMPER analysis, and predictions on shellfishing effects were discussed. A total of 248 species were recorded in hard-bottom communities, mainly characterized by mobile epifauna living on corals, crawling, and possessing a shell (molluscs) or a cuticle (crabs and echinoderms). Soft-bottom habitats contained 166 species, dominated by burrowing and sedentary species, especially shelled (largely bivalves) and worm-like organisms. Clear differences in species and trait composition between MPA and non-MPAs were highlighted in both habitats. Harvesting activities have community-wide effects that change the functional composition of invertebrate assemblages, in particular in terms of living habits and mobility. The observed shifts in benthic communities can affect the functioning of tropical coastal ecosystems and need to be included in small-scale fisheries management in poorly known tropical environments.
Adresse
Auteur institutionnel Thèse
Editeur Lieu de Publication Éditeur
Langue en Langue du Résumé Titre Original (up)
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 1054-3139, 1095-9289 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ alain.herve @ collection 1535
Lien permanent pour cet enregistrement
 

 
Auteur Carvalho, P.G.; Jupiter, S.D.; Januchowski-Hartley, F.A.; Goetze, J.; Claudet, J.; Weeks, R.; Humphries, A.; White, C.
Titre Optimized fishing through periodically harvested closures Type Article scientifique
Année 2019 Publication Revue Abrégée J. Appl. Ecol.
Volume 56 Numéro 8 Pages 1927-1936
Mots-Clés bioeconomic model; conservation; coral-reef fishes; fish behaviour; fisheries management; management; marine protected areas; marine reserves; new-zealand; outcomes; periodically harvested closures; population dynamics; vulnerability; yield
Résumé Periodically harvested closures are a widespread, centuries-old form of fisheries management that protects fish between pulse harvests and can generate high harvest efficiency by reducing fish wariness of fishing gear. However, the ability for periodic closures to also support high fisheries yields and healthy marine ecosystems is uncertain, despite increased promotion of periodic closures for managing fisheries and conserving ecosystems in the Indo-Pacific. We developed a bioeconomic fisheries model that considers changes in fish wariness, based on empirical field research, and quantified the extent to which periodic closures can simultaneously maximize harvest efficiency, fisheries yield and conservation of fish stocks. We found that periodic closures with a harvest schedule represented by closure for one to a few years between a single pulse harvest event can generate equivalent fisheries yield and stock abundance levels and greater harvest efficiency than achievable under conventional fisheries management with or without a permanent closure. Optimality of periodic closures at maximizing the triple objective of high harvest efficiency, high fisheries yield, and high stock abundance was robust to fish life history traits and to all but extreme levels of overfishing. With moderate overfishing, there emerged a trade-off between periodic closures that maximized harvest efficiency and no-take permanent closures that maximized yield; however, the gain in harvest efficiency outweighed the loss in yield for periodic closures when compared with permanent closures. Only with extreme overfishing, where fishing under nonspatial management would reduce the stock to <= 18% of its unfished level, was the harvest efficiency benefit too small for periodic closures to best meet the triple objective compared with permanent closures. Synthesis and applications. We show that periodically harvested closures can, in most cases, simultaneously maximize harvest efficiency, fisheries yield, and fish stock conservation beyond that achievable by no-take permanent closures or nonspatial management. Our results also provide design guidance, indicating that short closure periods between pulse harvest events are most appropriate for well-managed fisheries or areas with large periodic closures, whereas longer closure periods are more appropriate for small periodic closure areas and overfished systems.
Adresse
Auteur institutionnel Thèse
Editeur Lieu de Publication Éditeur
Langue English Langue du Résumé Titre Original (up)
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0021-8901 ISBN Médium
Région Expédition Conférence
Notes WOS:000478601300007 Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2619
Lien permanent pour cet enregistrement
 

 
Auteur Coll, M.; Steenbeek, J.; Lasram, F.B.; Mouillot, D.; Cury, P.
Titre 'Low-hanging fruit' for conservation of marine vertebrate species at risk in the Mediterranean Sea Type Article scientifique
Année 2015 Publication Frontiers in Microbiology Revue Abrégée
Volume 24 Numéro 2 Pages 226-239
Mots-Clés Conservation priorities; cumulative threats; IUCN diversities; marine biodiversity; Marine Protected Areas; Mediterranean Sea
Résumé AimConservation priorities need to take the feasibility of protection measures into account. In times of economic pressure it is essential to identify the low-hanging fruit' for conservation: areas where human impacts are lower and biological diversity is still high, and thus conservation is more feasible. LocationWe used the Mediterranean large marine ecosystem (LME) as a case study to identify the overlapping areas of low threats and high diversity of vertebrate species at risk. MethodsThis LME is the first in the world to have a complete regional IUCN Red List assessment of the native marine fish. We augmented these data with distributions of marine mammals, marine turtles and seabirds at risk, and we calculated the spatial distributions of species at risk (IUCN densities). Using cumulative threats we identified priority areas for conservation of species at risk' (PACS), where IUCN diversities are high and threats are low. We assessed whether IUCN diversities and PACS were spatially congruent among taxa and we quantified whether PACS corresponded to current and proposed protected areas. ResultsIUCN densities and PACS were not highly correlated spatially among taxa. Continental shelves and deep-sea slopes of the Alboran Sea, western Mediterranean and Tunisian Plateau/Gulf of Sidra are identified as relevant for fish species at risk. The eastern side of the western Mediterranean and the Adriatic Sea are identified as most relevant for endemic fish, and shelf and open sea areas distributed through the LME are most important for marine mammals and turtles at risk, while specific locations of the western Mediterranean Sea and the Aegean and Levantine seas are highlighted for seabirds. Main conclusionsLarge parts of the areas of PACS fell outside current or proposed frameworks to be prioritized for conservation. PACS may be suitable candidates for contributing to the 10% protection target for the Mediterranean Sea by 2020.
Adresse
Auteur institutionnel Thèse
Editeur Lieu de Publication Éditeur
Langue Langue du Résumé Titre Original (up)
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1102
Lien permanent pour cet enregistrement
 

 
Auteur Eduardo Nole, L.; Frédou, T.; Souza Lira, A.; Padovani Ferreira, B.; Bertrand, A.; Ménard, F.; Lucena Frédou, F.
Titre Identifying key habitat and spatial patterns of fish biodiversity in the tropical Brazilian continental shelf Type Article scientifique
Année 2018 Publication Revue Abrégée Continental Shelf Research
Volume 166 Numéro Pages 108-118
Mots-Clés Demersal fish assemblage; Fish assemblage structure; Habitat composition; Marine Protected Areas; Northeast Brazilian coast; Underwater footages
Résumé Knowledge of the spatial distribution of fish assemblages biodiversity and structure is essential for prioritizing areas of conservation. Here we describe the biodiversity and community structure of demersal fish assemblages and their habitat along the northeast Brazilian coast by combining bottom trawl data and underwater footage. Species composition was estimated by number and weight, while patterns of dominance were obtained based on frequency of occurrence and relative abundance. A total of 7235 individuals (830 kg), distributed in 24 orders, 49 families and 120 species were collected. Community structure was investigated through clustering analysis and by a non-metric multidimensional scaling technique. Finally, diversity was assessed based on six indices. Four major assemblages were identified, mainly associated with habitat type and depth range. The higher values of richness were found in sand substrate with rocks, coralline formations and sponges (SWCR) habitats, while higher values of diversity were found in habitats located on shallow waters (10–30 m). Further, assemblages associated with sponge-reef formations presented the highest values of richness and diversity. In management strategies of conservation, we thus recommend giving special attention on SWCR habitats, mainly those located on depths between 30 and 60 m. This can be achieved by an offshore expansion of existing MPAs and/or by the creation of new MPAs encompassing those environments.
Adresse
Auteur institutionnel Thèse
Editeur Lieu de Publication Éditeur
Langue Langue du Résumé Titre Original (up)
Éditeur de collection Titre de collection Titre de collection Abrégé
Volume de collection Numéro de collection Edition
ISSN 0278-4343 ISBN Médium
Région Expédition Conférence
Notes Approuvé pas de
Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2384
Lien permanent pour cet enregistrement