Éditeur(s) : Elsevier Science Bv
Résumé : The overexploitation of fishery resources has led to a major fisheries crisis. In this context, artisanal fisheries, and in particular small-scale coastal fisheries, appear as relevant alternatives for a sustainable use of coastal resources. Marine Protected Areas (MPA) are more and more used as management tools for these fisheries, as protection effects and targeted access regulations may benefit to commercial fishers. Managers and scientists need then quantitative information not only to adapt their management to the fishing activity present on their territory, but also to estimate the effects of MPA management on it. This study provides catch and effort estimates that are essential for appraising and managing the artisanal fishery in the Côte Bleue Marine Park (CBMP), a French Mediterranean MPA including two No-Take Zones of different age and size. A field protocol was defined and implemented between July 2009 and June 2010 within the CBMP. Seven métiers were identified and characterized by target species, gear type, fishing grounds and fishing periods. During the one-year studied period, 3512 fishing trips and 4645 fishing operations were performed by 30 active boats in the Côte Bleue fishing territory, amounting to 9500 km of immersed nets. In total, approximately 130 tons of catch were landed in the six CBMP harbors, out of which 58% depend on the three main species caught on the Côte Bleue: hake (Merluccius merluccius), gilthead seabream (Sparus aurata) and common sole (Solea solea). The presented methodology could be part of a long term monitoring requiring close collaboration with local fishers. It enables adaptive management with respect to changes in fishing pressure (from inside and outside the MPA) that may impact the environment and its resources.
Fisheries Research (0165-7836) (Elsevier Science Bv), 2014-06 , Vol. 154 , P. 93-101

Droits : 2014 Elsevier B.V. All rights reserved.
http://archimer.ifremer.fr/doc/00180/29120/29367.pdf
DOI:10.1016/j.fishres.2014.02.006
http://archimer.ifremer.fr/doc/00180/29120/

Éditeur(s) : Oxford university press
Résumé : The response of fish assemblages to changes in protection status is a major issue for both biodiversity conservation and fishery management. In New Caledonia, the Abore reef marine reserve harbours more than 500 fish species, and has been subjected to changes in protection status since 1988. The present study investigates the impact of these changes on a wide subset of species (213), based on underwater visual counts collected before the opening and after the closure to fishing of this marine protected area (MPA). We analysed the spatial and temporal variability in fish assemblage attributable to protection status, explicitly considering habitat. To understand the successive responses of fish assemblage to fishing and protection, the assessment models included four criteria de. ning species groups that partition the fish assemblage: trophic regime, adult size, mobility, and interest for fishing. We could therefore identify the negative impact of opening the MPA to fishing on piscivores and highly mobile species. Surprisingly, target species were not affected more than non-target species. Model results were used to identify species groups that respond to fishing and protection. These results utilize fisheries-related criteria to provide new insight into the response of fish assemblages to protection from the perspective of MPA monitoring.
ICES Journal of Marine Science (1054-3139) (Oxford university press), 2009 , Vol. 66 , N. 1 , P. 170-179

Droits : 2009 ICES/CIEM. Oxford Journals
http://archimer.ifremer.fr/doc/2009/publication-6130.pdf
DOI:10.1093/icesjms/fsn204
http://archimer.ifremer.fr/doc/00000/6130/

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
AimBiological invasions are major contributors to global change and native biodiversity decline. However, they are overlooked in marine conservation plans. Here, we examine for the first time the extent to which marine conservation planning research has addressed (or ignored) biological invasions. Furthermore, we explore the change of spatial priorities in conservation plans when different approaches are used to incorporate the presence and impacts of invasive species.LocationGlobal analysis with a focus on the Mediterranean Sea region.MethodsWe conducted a systematic literature review consisting of three steps: (1) article selection using a search engine, (2) abstract screening and (3) review of pertinent articles, which were identified in the second step. The information extracted included the scale and geographical location of each case study as well as the approach followed regarding invasive species. We also applied the software Marxan to produce and compare conservation plans for the Mediterranean Sea that either protect, or avoid areas impacted by invasives, or ignore the issue. One case study focused on the protection of critical habitats, and the other on endemic fish species.ResultsWe found that of 119 papers on marine spatial plans in specific biogeographic regions, only three (2.5%) explicitly took into account invasive species. When comparing the different conservation plans for each case study, we found that the majority of selected sites for protection (ca. 80%) changed in the critical habitat case study, while this proportion was lower but substantial (27%) in the endemic fish species case study.Main conclusionsBiological invasions are being widely disregarded when planning for conservation in the marine environment across local to global scales. More explicit consideration of biological invasions can significantly alter spatial conservation priorities. Future conservation plans should explicitly account for biological invasions to optimize the selection of marine protected areas.
ISSN: 1366-9516

hal-01431351
https://hal-univ-perp.archives-ouvertes.fr/hal-01431351
DOI : 10.1111/ddi.12491

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Well-designed and effectively managed networks of marine reserves can be effective tools for both fisheries management and biodiversity conservation. Connectivity, the demographic linking of local populations through the dispersal of individuals as larvae, juveniles or adults, is a key ecological factor to consider in marine reserve design, since it has important implications for the persistence of metapopulations and their recovery from disturbance. For marine reserves to protect biodiversity and enhance populations of species in fished areas, they must be able to sustain focal species (particularly fishery species) within their boundaries, and be spaced such that they can function as mutually replenishing networks whilst providing recruitment subsidies to fished areas. Thus the configuration (size, spacing and location) of individual reserves within a network should be informed by larval dispersal and movement patterns of the species for which protection is required. In the past, empirical data regarding larval dispersal and movement patterns of adults and juveniles of many tropical marine species have been unavailable or inaccessible to practitioners responsible for marine reserve design. Recent empirical studies using new technologies have also provided fresh insights into movement patterns of many species and redefined our understanding of connectivity among populations through larval dispersal. Our review of movement patterns of 34 families (210 species) of coral reef fishes demonstrates that movement patterns (home ranges, ontogenetic shifts and spawning migrations) vary among and within species, and are influenced by a range of factors (e.g. size, sex, behaviour, density, habitat characteristics, season, tide and time of day). Some species move <0.1–0.5 km (e.g. damselfishes, butterflyfishes and angelfishes), <0.5–3 km (e.g. most parrotfishes, goatfishes and surgeonfishes) or 3–10 km (e.g. large parrotfishes and wrasses), while others move tens to hundreds (e.g. some groupers, emperors, snappers and jacks) or thousands of kilometres (e.g. some sharks and tuna). Larval dispersal distances tend to be <5–15 km, and self-recruitment is common. Synthesising this information allows us, for the first time, to provide species, specific advice on the size, spacing and location of marine reserves in tropical marine ecosystems to maximise benefits for conservation and fisheries management for a range of taxa. We recommend that: (i) marine reserves should be more than twice the size of the home range of focal species (in all directions), thus marine reserves of various sizes will be required depending on which species require protection, how far they move, and if other effective protection is in place outside reserves; (ii) reserve spacing should be <15 km, with smaller reserves spaced more closely; and (iii) marine reserves should include habitats that are critical to the life history of focal species (e.g. home ranges, nursery grounds, migration corridors and spawning aggregations), and be located to accommodate movement patterns among these. We also provide practical advice for practitioners on how to use this information to design, evaluate and monitor the effectiveness of marine reserve networks within broader ecological, socioeconomic and management contexts.
ISSN: 1464-7931

Droits : http://creativecommons.org/licenses/by-nc-nd/
hal-01334353
https://hal-univ-perp.archives-ouvertes.fr/hal-01334353
https://hal-univ-perp.archives-ouvertes.fr/hal-01334353/document
https://hal-univ-perp.archives-ouvertes.fr/hal-01334353/file/Green_et_al-2015-Biological_Reviews.pdf
DOI : 10.1111/brv.12155

Éditeur(s) : HAL CCSD
Résumé : Integrating ecological connectivity into marine ecosystem management and planning is important, especially in a global context of severe fish stocks depletion and growing habitat degradation. Environmental tools such as Marine Protected Areas have been proposed to protect biodiversity, restore damaged ecosystems, sustain fisheries, and rebuild overexploited stocks. The effectiveness of marine protected areas depends in part on the maintenance of connectivity between marine populations, linked by ecological processes such as larval dispersal. In this thesis, we applied a biophysical model driven by ocean currents derived from satellite altimetry to evaluate connectivity between Western Indian Ocean reefs and across the current MPA system in the Mediterranean Sea. We applied different methods of analysis such as graph-theoretic and clustering. In the Western Indian Ocean, marine connectivity analyses show that the number of connections between reefs increases with fish pelagic larval duration. It also highlights a low connectivity across the region and a high interconnectivity within several regions (Mozambique Channel, Mascarene archipelago). In the Mediterranean Sea, connectance is globally low at the regional scale. This connectance is more important in Western than Eastern Mediterranean. Moreover, the marine connectivity analyses revealed high domestic connectivity rates. Depending on the study area, priority reefs or sites for MPA implementation are proposed. Finally, implications for transboundary marine policies and regional cooperation are discussed.
Intégrer les connaissances sur la connectivité écologique dans la gestion des écosystèmes marins est essentiel, surtout dans un contexte d'appauvrissement des ressources marines et de dégradation des habitats côtiers à l'échelle mondiale. Des outils environnementaux, tels que les Aires Marines Protégées ont été mises en œuvre pour protéger la biodiversité, restaurer les écosystèmes endommagés, soutenir les pêcheries et reconstituer les stocks surexploités. Leur efficacité dépend en partie du maintien de la connectivité entre les populations marines, assurée à travers divers processus écologiques dont la dispersion larvaire. Dans le cadre de ce travail de thèse, un modèle biophysique intégrant des données de courants, issues de mesures d'altimétrie par satellite, a été utilisé pour évaluer la connectivité entre les récifs de l'océan Indien d'une part, et à travers le réseau d'AMP de Méditerranée d'autre part. Différentes méthodes d'analyse ont été utilisées, telles que la théorie des graphes et le clustering. Dans l'océan Indien occidental, l'analyse des connectivités marines montre que le nombre de connexions entre les récifs augmente avec la durée de vie larvaire des poissons. Elle met également en évidence une faible connectivité à l'échelle de la région, mais une forte inter-connectivité au sein de plusieurs sous-régions (Canal du Mozambique, Mascareignes). En Méditerranée, la connectance est globalement faible à l'échelle régionale, bien que plus importante dans le bassin occidental que le bassin oriental. L'analyse des connectivités marines montre également un taux de connectivité élevé à l'échelle d'un même pays. Selon le cas d'étude, une liste de récifs ou de sites prioritaires dans la mise en œuvre des AMP a été proposée. Enfin, les implications de ces résultats en termes de politiques transfrontalières et de coopération régionale sont discutées.
https://tel.archives-ouvertes.fr/tel-01269631

NNT : 2015LARE0003
tel-01269631
https://tel.archives-ouvertes.fr/tel-01269631
https://tel.archives-ouvertes.fr/tel-01269631/document
https://tel.archives-ouvertes.fr/tel-01269631/file/2015lare0003_ECrochelet.pdf

Éditeur(s) : HAL CCSD
Résumé : The mangroves play a vital role in the ecological balance. They provide marine ecosystem resources and are involved in its stabilization and in the coastal protection. They constitute the growth areas of many species that feed marine species and particularly shrimp. We develop a standard fishery model by integrating mangroves area into the analysis. The extended model shows that mangrove plays animportant role in shrimp production and data related to it are well supported by the model. We analyze the e¤ects of mangrove on open access of the French Guiana shrimp fishery and show that mangrove is not the only factor that plays a vital role in the French Guiana shrimp fishery.
https://hal.univ-antilles.fr/hal-01383024

hal-01383024
https://hal.univ-antilles.fr/hal-01383024
https://hal.univ-antilles.fr/hal-01383024v2/document
https://hal.univ-antilles.fr/hal-01383024/file/Diop%20et%20al.%20%282016%29.pdf

Éditeur(s) : HAL CCSD
Résumé : International audience
Many countries are legally obliged to embrace ecosystem-based approaches to fisheries management. Reductions in bycatch and physical habitat damage are now commonplace, but mitigating more sophisticated impacts associated with the ecological functions of target fisheries species are in their infancy. Here we model the impacts of a parrotfish fishery on the future state and resilience of Caribbean coral reefs, enabling us to view the tradeoff between harvest and ecosystem health. We find that the implementation of a simple and enforceable size restriction of >30 cm provides a win:win outcome in the short term, delivering both ecological and fisheries benefits and leading to increased yield and greater coral recovery rate for a given harvest rate. However, maintaining resilient coral reefs even until 2030 requires the addition of harvest limitations (<10% of virgin fishable biomass) to cope with a changing climate and induced coral disturbances, even in reefs that are relatively healthy today. Managing parrotfish is not a panacea for protecting coral reefs but can play a role in sustaining the health of reefs and high-quality habitat for reef fisheries.
http://hal.univ-reunion.fr/hal-01369752

hal-01369752
http://hal.univ-reunion.fr/hal-01369752
DOI : 10.1073/pnas.1601529113

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Marine Protected Areas (MPAs) are increasingly used for biodiversity conservation and the management of sustainable fisheries. The use of taxonomic surrogates in routine monitoring of the reserve effects on fish assemblages may represent a promising method due to its substantial technical and economic benefits. However, higher taxonomic ranks should be used as surrogates with caution, especially for fish, where the approach is still virtually undocumented. This study aims to shed light on relationships between taxonomic relatedness and ecological similarity, which is crucial to assess the relevance of species surrogacy to reflect species-level information and detect changes in fish related to protection regimes. By analyzing data from a Mediterranean MPA, we show that rather being related to taxonomic relationships, the ability of higher taxa to reflect species-level patterns was explained in terms of aggregation level and distribution of species within taxa. Null models using random aggregations of species were created to identify the best surrogates able to depict changes in responses of assemblages to protection observed at the species-level. Comparison of null model predictions with the more classical higher-taxon approach revealed that the latter was not reliable because, unlike null model outcomes, surrogates determined empirically were not relevant for other subsequent independent monitoring. The effectiveness of species surrogates to depict changes in responses of assemblages to protection observed at the species-level depended (1) on the numerical resolution of the aggregation and (2) the magnitude of differences between protected and unprotected locations. Such findings suggest that surrogacy approaches may be applied for routine monitoring of Mediterranean reef fish communities, although mere empirical determinations of sufficient taxonomy seems to be not reliable, legitimizing the use of alternative methods based on null models. Guidelines for the careful use of species surrogacy in the ecological evaluation of MPAs on fish assemblages are provided.
ISSN: 0006-3207

hal-01174428
https://hal-univ-perp.archives-ouvertes.fr/hal-01174428
DOI : 10.1016/j.biocon.2015.06.002

Éditeur(s) : Oxford university press
Résumé : The eastern Baltic cod stock collapsed as a consequence of climate-driven adverse hydrographic conditions and over fishing and has remained at historically low levels. Spatio-temporal fishing closures [Marine Protected Areas (MPAs)] have been implemented since 1995, to protect and restore the spawning stock. However, no signs of recovery have been observed yet, either suggesting that MPAs are an inappropriate management measure or pointing towards suboptimal closure design. We used the spatially explicit fishery simulation model ISIS-Fish to evaluate proposed and implemented fishery closures, combining an age-structured population module with a multifleet exploitation module and a management module in a single model environment. The model is parameterized based on (i) the large amount of biological knowledge available for cod and (ii) an analysis of existing spatially disaggregated fishery data. As the population dynamics of eastern Baltic cod depend strongly on the climate-driven hydrographic regime, we considered two production regimes of the stock. MPAs were only effective for stock recovery when they reduced overall fishing effort. The performance of MPAs needs to be evaluated relative to environmental regimes, especially for stocks facing strong environmental variability.
ICES Journal of Marine Science (1054-3139) (Oxford university press), 2009 , Vol. 66 , N. 1 , P. 109-121

Droits : 2008 ICES/CIEM
http://archimer.ifremer.fr/doc/2009/publication-6094.pdf
DOI:10.1093/icesjms/fsn166
http://archimer.ifremer.fr/doc/00000/6094/

Éditeur(s) : Wiley
Résumé : This paper investigates some economic consequences of creating a marine reserve on both fishing and ecotourism, when the range of controllability of fishing effort is limited and the impact of the reserve on ecosystem is considered. The issue is illustrated by the example of creating a no-take zone in part of a region where fishing is managed through a limited entry license system, and which is inhabited by two interacting stocks: a stock of prey (fish) and a stock of predators (seals). While the former is targeted by commercial fishing, the latter is not subject to harvest but is a potential basis for a commercial non-extractive activity (seal watching). Analysis is conducted with the help of a bioeconomic model combining the features of marine reserve modeling and of multispecies modeling. Following a description of the model, results of several simulation runs are presented. These show that creating a marine reserve has more complex economic implications than predicted in studies focused exclusively on one stock and/or commercial fisheries. More specifically, the model shows that the dynamics of the two interacting stocks reduces the benefits of the no-take zone for the fishing industry, while it makes the creation of this zone provide an opportunity for the development of ecotourism. Due to this dynamics, the model suggests that the optimal size of the reserve is larger when ecotourism is taken into account along with fishing activities.
Natural Resource Modeling (1939-7445) (Wiley), 2002-12 , Vol. 15 , N. 4 , P. 387–411

Droits : 2002 Rocky Mountain Mathematics Consortium
http://archimer.ifremer.fr/doc/00244/35506/34010.pdf
DOI:10.1111/j.1939-7445.2002.tb00095.x
http://archimer.ifremer.fr/doc/00244/35506/

Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
Different marine habitats are characterised by different soundscapes. How or which differences may be representative of the habitat characteristics and/or community structure remains however to be explored. A growing project in passive acoustics is to find a way to use soundscapes to have information on the habitat and on its changes. In this study we have successfully tested the potential of two acoustic indices, i.e. the average sound pressure level and the acoustic complexity index based on the frequency spectrum. Inside and outside marine protected areas of Moorea Island (French Polynesia), sound pressure level was positively correlated with the characteristics of the substratum and acoustic complexity was positively correlated with fish diversity. It clearly shows soundscape can be used to evaluate the acoustic features of marine protected areas, which presented a significantly higher ambient sound pressure level and were more acoustically complex than non-protected areas. This study further emphasizes the importance of acoustics as a tool in the monitoring of marine environments and in the elaboration and management of future conservation plans. Coral reef ecosystems are among the most biologically diverse and complex marine ecosystems worldwide. In addition to their biological and ecological importance, coral reefs support major economic and physical functions (e.g. food production, tourism, biotechnology development and coastal protection) that are essential for many countries 1. Unfortunately, coral reefs are severely threatened: 20% of coral reefs can no longer be defined as such, another 25% are currently endangered and another 25% will be endangered by 2050 2. The frequency and severity of natural perturbations (e.g. cyclone, outbreaks of predators, particularly the crown-of-thorns starfish [COTS] Acanthaster planci) and anthropogenic perturbations (e.g. ocean acidification, pesticides, rising seawater temperatures) on coral reefs have greatly increased worldwide in the last three decades, and, as a consequence, reef communities (fish, coral and benthic invertebrates) have suffered unprecedented levels of decline 3,4
ISSN: 2045-2322

hal-01370610
https://hal-uvsq.archives-ouvertes.fr/hal-01370610
https://hal-uvsq.archives-ouvertes.fr/hal-01370610/document
https://hal-uvsq.archives-ouvertes.fr/hal-01370610/file/2016%20Sci.Rep.pdf
DOI : 10.1038/srep33326

Résumé : The study conducted in the framework of an agreement between Ifremer and the Local fisheries committee at Audierne is part of a project to restore spiny lobster Palinurus elephas stock levels in the Iroise Sea. It is supported by professional fishermen from Finistère and by the Regional fisheries committee of Brittany. After a brief review of the way lobster stocks are managed worldwide, followed by the major biological and ecological features of red lobster and the state of fisheries in Europe and North Africa, the very poor state of the resource along French coast is borne out by the statistics of landings. Various scenarios (not alternatives) to promote the rebuilding of the biomass are suggested: minimum landing size increase, seasonal closure of the fishery, berried females protection, no fishing zones. The drift of phyllosoma larvae during their long larval stage is addressed using a 3-D hydrodynamic simulation model.
L'étude réalisée dans le cadre d'une convention entre Ifremer et le Comité local des Pêches d'Audierne s'inscrit dans un projet de reconquête des niveaux de ressource en langouste rouge Palinurus elephas en mer d'Iroise soutenu par les pêcheurs professionnels de la pointe du Finistère et par le Comité régional des Pêches de Bretagne. Après avoir rappelé brièvement les modalités de gestion des stocks de langoustes dans le monde puis les grands traits biologiques et écologiques de la langouste rouge et l'état des pêcheries en Europe et dans le nord de l'Afrique, le très mauvais état de cette ressource sur les côtes françaises est confirmé au travers des statistiques de débarquement. Divers scénarios (non alternatifs) visant à favoriser la reconstitution d'une biomasse sont proposés : augmentation de la taille minimale au débarquement, fermeture saisonnière de la pêche, protection des femelles ovigères et création de zones protégées. La dérive des larves phyllosomes au cours de leur longue phase larvaire est abordée par un modèle de simulation hydrodynamique en trois dimensions.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2005/rapport-1198.pdf
http://archimer.ifremer.fr/doc/00000/1198/

Résumé : Le mérou géant, Epinephelus itajara, espèce en danger critique d’extinction au niveau mondial, est présent dans les eaux turbides et saumâtres de la Guyane française où l’espèce est exploitée par une pêcherie côtière. Dans la partie est du plateau continental guyanais, les mérous géants se localisent autour de tous les sites rocheux marins où ils se répartissent en fonction de la profondeur et du faciès (éboulis ou tombant). Les analyses des isotopes stables du carbone et de l’azote suggèrent qu’environ 30 % des mérous géants < 115 cm présents sur ces sites rocheux, proviendraient des mangroves alentours. Les analyses de contenus stomacaux révèlent un changement ontogénétique du régime alimentaire. Les petits individus (< 90 cm) s’alimentent principalement de Crustacés puis intègrent progressivement les poissons à leur alimentation jusqu’à devenir essentiellement piscivores au-delà de 140 cm. La population de Guyane est principalement composée d’individus juvéniles : seulement 8,5 % des individus capturés en Guyane a plus de 6 ans. Ces jeunes mérous sont très territoriaux durant les 4-5 premières années de leur vie puis ne sont plus retrouvés sur les sites rocheux. Le devenir de ces juvéniles est incertain, soit ils sont pêchés, soit ils migrent vers d’autres sites ou vers les agrégations de reproduction. Cependant, les mérous géants ne semblent pas se reproduire en Guyane. Il est possible que les conditions environnementales (forte turbidité et température) ne favorisent pas le développement gonadique, ce qui engendrerait une omission totale de reproduction. Le suivi par tags satellite suggère que les mérous géants migrent dans le sens des courants marins vers Trinidad-et-Tobago, potentiellement pour la reproduction. Aucun mouvement vers le Brésil n’a été mis en évidence bien que les stocks de mérous géants du Brésil et de Guyane semblent liés. En effet, ces deux stocks évoluent conjointement avec un déclin des populations au début des années 90. Le maintien de la population de mérou géant en Guyane se ferait grâce à l’apport de larves des sites d’agrégation du Brésil par le courant marin. La mortalité totale des mérous géants (0,65) est aussi élevée au sein de la réserve marine ainsi que sur les sites de pêche. Cela suggère que l’interdiction de pêche à la réserve n’est pas respectée et que les grands individus quittent la réserve pour des sites plus spacieux. En supposant que la population de mérous géants adultes a été réduite à cause de la pêche, une protection régionale des individus > 150 cm doit être instaurée afin de régénérer le stock d’individus matures. Il semble nécessaire de développer une politique de gestion internationale de l’espèce, surtout entre la Guyane et le Brésil, afin de conserver les populations de mérous géants d’Amérique du Sud.
The critically endangered Goliath Grouper, Epinephelus itajara, is found in the turbid and brackish waters of French Guiana, where the species is subject to a coastal fishery. Goliath Grouper populations inhabit all rocky habitats and exhibit increasing abundance with depth. Around 30% of individuals less than 115 cm may derive from the abundant mangrove habitat along the french Guiana coast. There is a ontogenetic shift of the diet, primarily crustacivorous, individuals >140 cm become piscivorous. The Goliath Grouper population in French Guiana is composed primarily og juvelines. The fate of the juvelines is unknonw, some may be caught in the fishery, others may move to other habitat. No evidence of spawning or gonadal readiness was found in french Guiana. it is possible that environmental conditions (high turbidity and temperature) are not conducive to reproductive activity. Goliath Grouper may migrate down current from French Guiana to Trinidad and Tobago or further. No movement of Goliath Grouper was found against the current toward Brazil. French Guiana juveniles may be derived from spawns occuring off Brazil. Calculated total mortality of Goliath Grouper off French Guiana is high (0.65) in both fished and protected areas suggesting that illegal fishing is occuring within the protected area, or that emigration rates are high. Assuming that the adult population of Goliath Grouper in French Guiana has been reduced due to fishing, protection of spawning-size adults (larger than about 150 cm TL) should be instated.

http://www.theses.fr/2014AGUY0721/document

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Marine Protected Areas (MPAs), if well designed and managed, can produce conservation benefits to fish assemblages within no-take zones and fishery benefits in neighboring areas through ‘spillover’. However, although plenty of studies have provided evidence of the benefits produced within MPA boundaries, overall benefits to local fisheries, especially via spillover, seem to be still unclear. Because of the lost fishing grounds following an MPA establishment, local fishermen usually oppose MPAs. There is, therefore, the urgent need for a better understanding of the mechanism(s) through which MPAs can export fishable fish biomass towards adjacent fished areas, a process that could counterbalance the loss of fishing grounds. Here we review the literature on spillover for refining the terminology, detailing the underlying mechanisms and identifying both the existing and needed methodological approaches to measure spillover. Operationally, two types of spillover should be considered: ecological spillover (i.e. the net export of juvenile, subadult and adult biomass from MPAs outwards driven by density-dependent processes) and the fishery spillover (i.e. the proportion of this biomass that can be fished, taking into account regulations and accessibility). Underwater visual census and tagging/tracking may allow getting evidence of ecological spillover, while experimental catch data are essential to assess and monitor fishery spillover, which is the main component of MPAs that can provide direct benefit to local fisheries.
ISSN: 1617-1381

hal-01325478
https://hal-univ-perp.archives-ouvertes.fr/hal-01325478
DOI : 10.1016/j.jnc.2016.04.004

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : La Martinique possède 55 km2 de récifs coralliens, 50 d’herbiers et 20 de mangroves. Ces trois écosystèmes produisent des biens et services dont la valeur est estimée à quelque 250 millions d’euros par an. Près de 60 % de cette valeur est issue des usages directs liés aux activités récréatives (plongée, excursion, récréation balnéaire) induites pour l’essentiel par le tourisme et celles liées à la pêche (professionnelle et de plaisancière). Les services écosystémiques (assimilés aux usages indirects) tels que la protection des côtes, l’absorption/séquestration de carbone, la production de biomasse de poissons et l’épuration de l’eau sont conséquents puisque leur valeur annuelle s’élève à 94 millions € soit 38 % de la valeur totale. La valeur de ce qui a trait au non-usage des récifs, herbiers et mangroves (lié à la volonté de transmettre un patrimoine écologique pour l’essentiel ou encore à la satisfaction de savoir que les récifs sont en bon état) se traduit par une création de valeur de l’ordre de 10 millions €/an. Les herbiers et les mangroves contribuent le plus (par km2) à la création de valeur (respectivement 2,16 millions €/km2, 1,87 million €/km2 contre 1,78 million €/km2 pour les récifs). Ils doivent donc bénéficier de mesures de protection et surtout de valorisation au même titre que les récifs coralliens qui font déjà l’objet d’une attention particulière.
Martinique possesses 55 km2 of coral reefs, 50 of sea grass and 20 of mangroves. These three ecosystems produce services for a value estimated at 250 millions € per year. About 60% of this value originates from directs uses such as recreational activities (diving, excursions, beach activities, etc.) induce by tourism and fishery. Ecosystem services (indirect uses) such as coastal protection, carbon sequestration, biomass production and water purification are significant since their sum value reaches annually 94 millions € (38% of the total economic value). Non-use value links to the improvement of the health of coastal ecosystem is estimated to 10 millions € per year. At the ecosystem level, sea grass and mangrove contribute the more (per km2) to the wealth creation (respectively 2,16 millions €/km2, 1,87 million €/km2 against 1,78 million €/km2 for the reefs). They need therefore to benefit from protection and management measures in the same magnitude than the reefs already received.
Martinique

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.4410
http://journals.openedition.org/etudescaribeennes/4410

Éditeur(s) : Oxford university press
Résumé : There is increasing evidence from previous studies, and from fishers' observations, that coastal dolphins use fishing nets as an easily accessible feeding source, damaging or depredating fish caught in the nets. This study investigates the impact of dolphin depredation on artisanal trammelnets by analysing the catch composition of 614 artisanal fishing operations in the Bonifacio Strait Natural Reserve (France). Common bottlenose dolphins (Tursiops truncatus) attacked, on average, 12.4% of the nets and damaged 8.3% of the catch. However, attacked nets were characterized by statistically significantly higher catch per unit effort than unattacked ones. Catch composition also differed significantly after dolphin attacks; bentho-pelagic fish were more represented and reef-associated fish less represented. Our results suggest that (i) dolphins are attracted by high fish densities in the fishing area and/or nets, and (ii) their attacks induce specific fish-avoidance behaviour, according to the fish position in the water column. Although dolphins depredate a small part of the catch, damage to nets, not yet assessed in this area, could weaken the benefits that reserves can provide to artisanal fisheries.
ICES Journal of Marine Science (1054-3139) (Oxford university press), 2009-05 , Vol. 66 , N. 4 , P. 699-707

Droits : 2009 ICES/CIEM. Oxford Journals
http://archimer.ifremer.fr/doc/2009/publication-6808.pdf
DOI:10.1093/icesjms/fsp036
http://archimer.ifremer.fr/doc/00000/6808/

Éditeur(s) : HAL CCSD The Royal Society
Résumé : International audience
Conservation commonly requires trade-offs between social and ecological goals. For tropical small-scale fisheries, spatial scales of socially appropriate management are generally small— the median no-take locally managed marine area (LMMA) area throughout the Pacific is less than 1 km 2. This is of particular concern for large coral reef fishes, such as many species of grouper, which migrate to aggregations to spawn. Current data suggest that the catchment areas (i.e. total area from which individuals are drawn) of such aggregations are at spatial scales that preclude effective community-based management with no-take LMMAs. We used acoustic telemetry and tag-returns to examine reproductive migrations and catchment areas of the grouper Epinephelus fuscoguttatus at a spawning aggregation in Papua New Guinea. Protection of the resultant catchment area of approximately 16 km 2 using a no-take LMMA is socially untenable here and throughout much of the Pacific region. However, we found that spawning migrations were skewed towards shorter distances. Consequently, expanding the current 0.2 km 2 no-take LMMA to 1–2 km 2 would protect approximately 30–50% of the spawning population throughout the non-spawning season. Contrasting with current knowledge, our results demonstrate that species with moderate reproductive migrations can be managed at scales congruous with spatially restricted management tools.
ISSN: 2054-5703

Droits : http://creativecommons.org/licenses/by/
hal-01297717
https://hal-univ-perp.archives-ouvertes.fr/hal-01297717
https://hal-univ-perp.archives-ouvertes.fr/hal-01297717/document
https://hal-univ-perp.archives-ouvertes.fr/hal-01297717/file/150694.full.pdf
DOI : 10.1098/rsos.150694

Éditeur(s) : HAL CCSD Ecological Society of America
Résumé : Reliable assessment of fish origin is of critical importance for exploited species, since nursery areas must be identified and protected to maintain recruitment to the adult stock. During the last two decades, otolith chemical signatures (or "fingerprints") have been increasingly used as tools to discriminate between coastal habitats. However, correct assessment of fish origin from otolith fingerprints depends on various environmental and methodological parameters, including the choice of the statistical method used to assign fish to unknown origin. Among the available methods of classification, Linear Discriminant Analysis (LDA) is the most frequently used, although it assumes data are multivariate normal with homogeneous within-group dispersions, conditions that are not always met by otolith chemical data, even after transformation. Other less constrained classification methods are available, but there is a current lack of comparative analysis in applications to otolith microchemistry. Here, we assessed stock identification accuracy for four classification methods (LDA, Quadratic Discriminant Analysis [QDA], Random Forests [RF], and Artificial Neural Networks [ANN]), through the use of three distinct data sets. In each case, all possible combinations of chemical elements were examined to identify the elements to be used for optimal accuracy in fish assignment to their actual origin. Our study shows that accuracy differs according to the model and the number of elements considered. Best combinations did not include all the elements measured, and it was not possible to define an ad hoc multielement combination for accurate site discrimination. Among all the models tested, RF and ANN performed best, especially for complex data sets (e. g., with numerous fish species and/or chemical elements involved). However, for these data, RF was less time-consuming and more interpretable than ANN, and far more efficient and less demanding in terms of assumptions than LDA or QDA. Therefore, when LDA and QDA assumptions cannot be reached, the use of machine learning methods, such as RF, should be preferred for stock assessment and nursery identification based on otolith microchemistry, especially when data set include multispecific otolith signatures and/or many chemical elements.
ISSN: 1051-0761

hal-00644549
https://hal.archives-ouvertes.fr/hal-00644549
DOI : 10.1890/09-1887.1

Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
Although coral reefs support the largest concentrations of marine biodiversity worldwide, the extent to which the global system of marine-protected areas (MPAs) represents individual species and the breadth of evolutionary history across the Tree of Life has never been quantified. Here we show that only 5.7% of scleractinian coral species and 21.7% of labrid fish species reach the minimum protection target of 10% of their geographic ranges within MPAs. We also estimate that the current global MPA system secures only 1.7% of the Tree of Life for corals, and 17.6% for fishes. Regionally, the Atlantic and Eastern Pacific show the greatest deficit of protection for corals while for fishes this deficit is located primarily in the Western Indian Ocean and in the Central Pacific. Our results call for a global coordinated expansion of current conservation efforts to fully secure the Tree of Life on coral reefs.
ISSN: 2041-1723

hal-01282920
https://hal-univ-perp.archives-ouvertes.fr/hal-01282920
https://hal-univ-perp.archives-ouvertes.fr/hal-01282920/document
https://hal-univ-perp.archives-ouvertes.fr/hal-01282920/file/ncomms10359.pdf
DOI : 10.1038/ncomms10359

Résumé : Sea fish farms with production of more than 20 tons per year in France must obtain two operating licences: (i) one for Sea Farming (AECM), with the aim of ensuring that the granted site and use of the maritime public domain for exploitation will respect all restrictions of general interest; (ii) one for regulating Facilities Classified for the Protection of the Environment (ICPE). Although the first one requires a relatively simple licence request file, the second one demands a very complete file, which includes, beyond the notice of exploitation information, a complete impact study, as well as a hazards study and a health and safety notice. In this context, petitioners in Corsica (adjustment of status or new exploitation) are faced with the same difficulties, which highlighted the need for a methodological guide adapted to each region's specific situation, assembling in particular the necessary baseline data (legal, zootechnical, geographical, climatic, socio-economic, ecological...) as well as recognised methods for evaluating the potential effects of the farm on the environment. Development of this guide was supported by ADEC and supervised by a steering committee composed of representatives from the administrations concerned, fish farmers and scientific bodies. The significant aspects dealt with the effects of fish farming on Posidonie herbarium, a protected species very present in Corsica and with coordinating the two AECM and ICPE procedures. For each part of the ICPE file, the guide introduces the technical or scientific context and, depending upon the case, the state of the art, sources of available data, acquisition and methods of acquiring measurements and of assessing the potential effects, as well as practical editing recommendations. Finally, the guide is made complete by a model schedule of conditions designed to help petitioners to have a specialist research department incorporate all or part of the file. This guide primarily concerns first-time marine facilities for exploitation in Corsica, conceived of as in the open sea rather than in confined spaces. Nonetheless, any fish farmer or future fish farmer needing to process a request for an exploitation licence may find it useful.
Les piscicultures marines de plus de 20 t/an de production sont soumises en France à l'obtention de deux autorisations d'exploiter : (i) celle au titre des Cultures Marines (AECM), visant à s'assurer que le site concédé et l'usage du domaine public maritime pour l'exploitation permettent de respecter l'ensemble des contraintes d'intérêt général ; (ii) celle au titre de la réglementation des Installations Classées pour la Protection de l'Environnement (ICPE). Si la première nécessite un dossier de demande d'autorisation relativement simple, la seconde requiert un dossier très complet, qui comprend, outre une notice de renseignements sur l'exploitation, une étude d'impact complète, ainsi qu'une étude des dangers et une notice d'hygiène et de sécurité. Dans ce contexte, les demandeurs en Corse (régularisation ou exploitation nouvelle) sont confrontés aux mêmes difficultés, ce qui a mis en évidence le besoin d'un guide méthodologique adapté aux spécificités régionales, rassemblant en particulier les données de base nécessaires (juridiques, zootechniques, géographiques, climatiques, socio-économiques, écologiques...) ainsi que les méthodes reconnues de l'évaluation des effets potentiels de la ferme sur l'environnement. L'élaboration de ce guide a été soutenue par l'ADEC et suivie par un comité de pilotage composé de représentants des administrations concernées, des pisciculteurs et d'organismes scientifiques. Les aspects importants ont porté sur les effets de la pisciculture sur l'herbier de Posidonie, espèce protégée très présente en Corse et sur la coordination entre les deux procédures AECM et ICPE. Pour chaque partie du dossier ICPE, le guide présente le contexte technique ou scientifique et selon le cas, l'état de l'art, les sources de données disponibles, les méthodes d'acquisition des mesures et d'évaluation des effets potentiels, ainsi que des recommandations pratiques de rédaction. Enfin, le guide est complété par un cahier des charges type destiné à aider les demandeurs à confier à un bureau d'étude spécialisé la réalisation de tout ou partie de la constitution du dossier. Ce guide concerne prioritairement les installations marines de nouvelles exploitations en Corse, envisagées en mer ouverte plutôt que dans des espaces confinés. Néanmoins tout pisciculteur ou futur pisciculteur devant instruire une demande d'autorisation d'exploiter peut y trouver intérêt.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2004/rapport-2188.pdf
http://archimer.ifremer.fr/doc/00000/2188/