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 Nature Publishing Group
Résumé : International audience
Marine biological invasions threaten biodiversity worldwide. Here we explore how Marine Protected areas, by reducing human use of the coast, confer resilience against the introduction of non-indigenous species (NIS), using two very different Pacific islands as case studies for developing and testing mathematical models. We quantified NIS vectors and promoters on Vancouver (Canada) and Moorea (French Polynesia) islands, sampled and barcoded NIS, and tested models at different spatial scales with different types of interaction among vectors and between marine protection and NIS frequency. In our results NIS were negatively correlated with the dimension of the protected areas and the intensity of the protection. Small to medium geographical scale protection seemed to be efficient against NIS introductions. The likely benefit of MPAs was by exclusion of aquaculture, principally in Canada. These results emphasize the importance of marine protected areas for biodiversity conservation, and suggest that small or medium protected zones would confer efficient protection against NIS introduction.
ISSN: 2045-2322

hal-01381251
https://hal-univ-perp.archives-ouvertes.fr/hal-01381251
https://hal-univ-perp.archives-ouvertes.fr/hal-01381251/document
https://hal-univ-perp.archives-ouvertes.fr/hal-01381251/file/rate%20of%20biological%20invasions.pdf
DOI : 10.1038/srep33013

Résumé : After a period of rapid development of the sites (an increase in both reared surface area and production), tropical shrimp aquaculture is currently being faced with critical problems due to economical and ecological constraints. In many countries with favourable conditions for shrimp aquaculture such as indonesia or Vietnam, sites are often badly selected and/or over-exploited. This conducts to sorne extent to decreases or collapses in the production due to the difficulty in predicting the maximum production capacity of the sites. Furthermore, it appears that production sustainability depends on many factors among which socio-economy and ecolo gy are of prime importance. The STD3 project titled « Assessment of tropical shrimp aquaculture impact on the environment in tropical countries using hydrobiology, ecology and remote sensing as helping tools for diagnosis )) was initiated in 1994, with the aim to study the sustainability of marine shrimp aquaculture in tropical areas, main! y Indonesia and Vietnam, through the following tasks: (i) improve site selection and study the impact of aquaculture on marine environments presenting a variable sensitivity to organic sewage, (ii) analyse the socio-economical aspects and profitability of the aquaculture industry and of common resources (iii) use remote sensing and geographical data bases for diagnosis and monitoring of site degradation (iv) reinforce the capacity of Asian scientists through training. Severa! aquaculture sites have been investigated in the Lampung region (South Sumatra, Indonesia), the Mekong delta (Vietnam) and on the West coast of New-Caledonia, providing a large range of typical ecosystems encountered in Asia and in the Pacifie, from coralline sites to coastal plains with mangrove and deltaic areas. The study concerned the spatial structure and seasonal influence of these ecosystems, the temporal variation during the course of the project (3 years) and the relation between the ecological structure and farm productions. Remote sensing provides a synoptic vision over large land expanses. Severa! scenes were processed for landuse mapping using conventional classification techniques. Concerning water quality assessment, a general relation for the Java sea was found between image and field data in terms of total suspended matter. Applying this relation to a new site in Sumatra has provided an initial approach to water type and, together with land use mapping, a preliminary assessment of the suitability of the area to shrimp aquaculture development. Socio-economic research has been focused on the identification ofneeds for collective action, including public policy, in the perspective of shrimp farming sustainability. The main concern is in the regulation of shrimp farming intensification and extensification at the scale of coastal ecosystemic entities in a common property resource management perspective. The common considered here is coastal water quality. Comparing the local development profiles and the institutional grounds for the design and implementation of collective management rules shows that variables such as land tenure system, farm owner socio-economic profile, social homogeneity or heterogeneity of the farmers are key factors to analyse the potential for sustainability. The defmition of water quality and the possible means to ensure its collective management are discussed. The main conclusion is that the economie incentives to farming development are strong but there is no significant difference among traditional, semi-intensive and intensive systems in terms of economie efficiency or wealth distribution. The description of the functioning of the different kinds of ecosystems make it possible to give an advice concerning the positioning of the activity inside the ecosystem, and furthermore to have a reference state in order to determine the impact of the activity on the coastal environnement. This impact can be summarized as an increase in the concentration of total suspended matt€?r, of particulate organic matter and of sulfate reducing bacterias. This organic ma~.er is either issued from rearing activities or from telluric origine, due to mangrove eradication when building the ponds. An evaluation of the relationship existing between productivity and characteristics of each ecosystem bas been conducted by correlating ecological indicators data (concentration of total suspended matter, particulate organic matter, chlorophyll, percentage of pheopigments in total pigments and cyanobacteria and sulfatereducing bacteria in water and sediments) with the average production of the farms. This comparison lead to the compilation of a scale of observed production integrating the range of these environmental parameters with shrimp production levels, bound to facilitate the positioning of shrimp farming in relation with the confmement leve! of each ecosystem. Lastly, ali geographie data originated from the various compartments of the study have been geo-referenced and loaded into a geographical information system. This allows to display any query made on spatial variables and their related statistical data, including the ir variations over the last few years and to reveal patterns and phenomena otherwise not obvious.
Le programme mis en oeuvre par la DRV (Paris, CREMA-L'Houmeau, DELIAO Brest, COP Tahiti, GIE/RA Nouvelle Calédonie), dans le cadre d'un projet européen STD3 «(Sciences et Technique au Service du Développement», en collaboration avec l'Université de Montpellier II, l'Ecole Nationale d'Agronomie de Rennes, l'ITC (Hollande), l'Institut Océanographique de Nha Trang (Vietnam), le BADC de Jepara et le BPPT de Jakarta (Indonésie), avait pour but la mise au point de méthodes permettant d'améliorer la sélection des sites ainsi que le suivi du développement et de l'impact de l'aquaculture des crevettes Péneides en milieu tropical pour éviter la surexploitation. Quatre axes de recherche ont été défmis : a) identifier la nature et quantifier les rejets de déchets issus de ce type d'aquaculture, b) définir les caractéristiques écologiques des écosystèmes susceptibles d'accueillir l'activité aquacole et suivre leur évolution sous l'influence des rejets, c) déterminer l'influence de la gestion des fermes et des ressources (aspects économiques) sur les performances de productivité, d) déterminer la capacité de la télédétection comme outil de diagnostic d'impact à l'échelle de la région, e) mener un programme de formation d'étudiants et jeunes chercheurs Vietnamiens et Indonésiens.

Droits : 1998 Ifremer
http://archimer.ifremer.fr/doc/00132/24357/22357.pdf
http://archimer.ifremer.fr/doc/00132/24357/

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
With only a narrow opening through the Gibraltar and Suez Canals, the Mediterranean Sea is one of thelargest semi-enclosed seas. The marine flora and fauna are some of the richest in the world, relative to itssize, particularly in the coastal habitats, which are also characterized by numerous endemic speciesalthough the introduction of non-indigenous species threatens its rich and unique biodiversity. Followingthe opening of the Suez Canal, and in combination with shipping and aquaculture activities, nonindigenousspecies (NIS) introduction has had measurable impacts on the Mediterranean. Lagoon ecosystemsalong the French coastline, with approx. 100 NIS identified, are considered hot-spot areas forthese species. Rapid assessment sampling for sessile benthic species together with DNA barcoding is arapid, easy and cheap method to detect non-indigenous species. Two nearby and different ecosystemswere sampled for invertebrate species: Saint-Nazaire lagoon, a Special Protection Area within the Natura2000 Network and Canet port, a marina in a small village. The DNA barcoding tool for species identificationwas used for confirming the taxonomy. This showed that, despite the Saint-Nazaire Lagoonclassification within the Natura 2000 network, it is already contaminated with a single NIS that wasfound in high densities and is clearly beginning to dominate the system. It is proposed that a rapidassessment of the sampled environment and the DNA barcode approach are efficient and can providesufficient information on the new target species to be used in conservation planning and ongoingmanagement efforts.
ISSN: 0272-7714

hal-01488926
https://hal-univ-perp.archives-ouvertes.fr/hal-01488926
DOI : 10.1016/j.ecss.2017.02.004

Éditeur(s) : Physiomar 08 Physilogical aspects of reproduction, nutrition and growth "Marine molluscs in a changing environment"
Résumé : Bonamiosis is a parasitic disease (causative agent: Bonamia ostreae) affecting the European flat oyster Ostrea edulis, responsible for a drastic decline in the aquaculture production of this oyster species. Therefore a selective breeding program for resistance to bonamiosis has been undertaken since 1985 bu Ifremer, leading to the production of several selected oyster families. In the present study, a 6-month cohabitation challenge experiment was performed in order to transmit the disease from wild oysters (injected with the parasite) to two tested families of oysters originating from the selective breeding program. Mortalities were checked daily, and ventricular heart smears were performed on dying or moribund oysters to detect the level of infection to B. ostreae. The first infections occurred after 4 months of challenge in the tested oysters (Family 1 and Family 2). The cumulative mortalities after 5 monts were 58% for the wil oysters, 9% for Family 1 (20-month old at the beginning of the experiment) and 20% for Family 2 (8-month, old). The parasite could be detected in 66.8% of the dying wild oysters, 67.5% of the dying oysters of Family 1, 89% of the dying oysters of Family 2 and only 11% of the surviving oysters of Family 2. The mortality was significantly higher in Family 2 thant in Family 1 (x2= 20.87, p<0.001, d.f.) as well as the level of infection by the parasite found in heart smear (x2=24.34, p<0.001, 4 d.f.). This result demonstrates that prespawning oysters as yong as 1 year-old can become infected with the parasite and die from bonamiosis. This result is inconsistent with the commonly accepted critical age of 2 years-old for the disease development. The most probable cause of the dscrepancy in the development of bonamiosis between the 2 tested families is a difference in genetic background.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2008/acte-4535.pdf
http://archimer.ifremer.fr/doc/00000/4535/

Éditeur(s) : Elsevier
Résumé : Herbivorous (20% vegetable protein, 40% carbohydrate) and carnivorous diets (40% marine animal protein, 20% carbohydrate) were experimentally tested to assess their effect on the energy balance and energetic substrates utilized by postlarvae (PL's /15 days) and juvenile shrimp (3-6 g) of Litopenaeus vannamei. Postlarval stage 60 (PL60, early juveniles) shrimps fed HeD and CaD diets, then late juveniles (3-6 g) acclimated to the same diets were tested for their respective energy partitioning potential. No significant differences (p>0.05) on growth were obtained in early juveniles (mean final wet weight of 0.19 g). However in late juvenile stages a significant difference (p<0.05) in growth rate was observed. In terms of energy partitioning, both early and late juveniles seem to spend more energy in respiratory metabolism than in the elimination of excretion products. A change in feed composition based on quality protein sources induced some modifications on shrimp's activity measured by heat increment. Shrimps fed with an herbivorous diet showed a higher heat increment. Interestingly, the early stages of L vannamei display a remarkable capacity to assimilate a plant protein-based and a high carbohydrate level diet. Such capacity with a stimulation of genes would lead to a good adaptation of juveniles receiving all-plant diets to sustain growth performances up to a marketable size. The implications of these findings for the shrimp farming feeding costs are briefly discussed. (C) 2009 Elsevier B.V. All rights reserved.
Aquaculture (0044-8486) (Elsevier), 2009-11 , Vol. 296 , N. 1-2 , P. 123-128

Droits : 2009 Elsevier B.V. All rights reserved.
http://archimer.ifremer.fr/doc/2009/publication-7402.pdf
DOI:10.1016/j.aquaculture.2009.08.007
http://archimer.ifremer.fr/doc/00000/7402/

Résumé : Marine capture fisheries in Jamaica is primarily artisanal in nature ansd is conducted maiinly by fishermen operating from canoes. Approximately 95% of these fishermen operate on the coastal shelf and its associated banks. The commercial species harvested comprise bottom-dwelling, coral reef species and free swimming species of finfish. Other fishery resources of commercial value include marine shrimp, conch and lobsters. Catch statistics are not available for all species, but the Department of Fisheries reports a slight decline in fishery production with production decreasing from 16 milion lbs in 1990, despite the fact that fishing efforts have doubled. Over this period the number of registered fishermen has grown from 12 000 to 16 000, al of whom are engaged in full-time fishing. There arealso part-time fishermen who are not registered. The decline in fish catch is accompanied by a decrease in fish size and quality, suggesting that the fisheries are under pressure and have already exceeded optimum production in relation to vailable resources. As a result the economic returns to fishermen are declining. There are also other problems, such as high incidence of conflicts among fishermen at sea, the high cost of purchasing boats, outboard engine fuel, and equipment, with together with the dangers involved in fishing offshore (piracy, and praedial larceny) create serious social ans economic difficulties for fishermen. Notwithstanding, there is an apparent move on the part of the fishermen to leave the industryor to seek alternative forms of employment. In fact, the Department ofFisheries reports that it is still reciving applications for new licences to operate fishing boats. This is probably due to the fact that where the basis of a community is fishing, it becomes difficult to introduce alternative forms of employment, such as cottage industries, village crafts and other trades. In 1987 the Jamaica Department of Fisheries prepared a Management plan which proposed several conservation measures to promote the efficient use of fisheries resources and to control the development of the Fishery in such a way that the country would receive highest benefits. Adequate attention was given to limitations on fishing gear, institution of closed seasons and related legislation. Strategies to diversify the marine fishing were also proposed. The 1990 five year Devlopment Plan for marine fisheries also focuses on proper resource management in order to reverse trends associated with the overexploitation of marine resources. According to the plan, emphasis will be placed on inland fisheries and mariculture in order to reduce pressure on the fisheries. Inland fisheries in the form of freshwater fish fanning has expanded significantly over the past 10 years with production increasing from less than 0,5 million lbs. in 1980 to in excess of 6.0 million lbs. in 1989. However, some freshwater fish farmers are already experiencing serious competition for water usage and, to a lesser extent for land from crop-producing farmers. The Ministry of Agriculture is of the view that marine cage culture technologically has the potential for introduction in Jamaica . This technologyhas been successfully developed in Norway and the technology is currentlty being experimentally utilized in several countries in the area. The technology, if widely utilized in Jamaica, couls significantly reduce pressure on fisheries, making fishing more cost effective and improve the economic returns to fishermen. Already there exist some technical and institutional capabilities in Jamaica to support commercial development of marine cage culture. The Department of Fisheries has highly trained personnel in aquaculture and marine fisherie, some of whom are directly responsible for the success of freshwater fish fanning. In adition, the Marine Laboratory at the Univesity of the West Indies (UWI) is caarying research on hatchery facilities for marine cage farming. The Department of Fisheries will seek the collaboration ofg the marine unit at UWI which could provide fingerlings of selected marine species for cage 1
Les pêcheries de captage marin en Jamaïque sont principalement de nature artisanale et elles sont dirigées principalement par les pêcheurs qui travaillent depuis des canoës. Environ 95 % de ces pêcheurs travaillent sur la plaine côtière et ses bancs associés. Les espèces commerciales récoltées comprennent les espèces benthiques, les espèces de corail et les espèces de poisson marin de nage libre. D'autres ressources de pêcheries de valeur commerciale comprennent la crevette, la conque et le homard. Les statistiques des pêches ne sont pas disponibles pour toutes les espèces, mais le Département des Pêcheries fait état d'une légère réduction de production de pêcheries, la production se réduisant de 16 millions de livres en 1990, en dépit du fait que les efforts de la pêche ont doublé. Sur cette période le nombre de pêcheurs inscrits a augmenté de 12 000 à 16 000, dont tous sont occupés à plein temps à la pêche. Il y a aussi des pêcheurs à mi-temps qui ne sont pas inscrits. La réduction des pêches est accompagnée d'une réduction de la taille et la qualité des poissons, ce qui implique que les pêcheries sont sous pression et qu'elles ont déjà dépassé la production optimum par rapport aux ressources disponibles. En conséquence, les rendements pour les pêcheurs sont en baisse. Il y a aussi d'autres problèmes, tels qu'un taux élevé de conflits entre les pêcheurs en mer, le coût élevé pour acheter les bateaux, le combustible pour les moteurs hors-bord, et le matériel, ainsi que les dangers impliqués dans la pêche offshore (le piratage, et le vol prédial) ont créé de graves problèmes sociaux et économiques pour les pêcheurs. Néanmoins, il y a une tendance évidente chez les pêcheurs de quitter l'industrie ou de chercher du travail dans d'autres domaines. En fait, le Département des Pêcheries signale qu'il continue de recevoir des demandes de nouveaux permis pour opérer les bateaux de pêche. Ceci est probablement attribuable au fait que là où la base d'une communauté est la pêche, il est difficile d'y introduire des formes alternatives de travail, telles que l'industrie artisanale, l'artisanat de village ou d'autres métiers. Le Département des Pêcheries de la Jamaïque a préparé en 1987 un Projet de gestion qui proposait plusieurs mesures de conservation afin d'encourager l'utilisation efficace des ressources des pêcheries et de contrôler le développement de la Pêcherie de manière que le pays touche le plus de bénéfices. Une attention adéquate a été prêtée aux limitations sur les engins de la pêche, l'établissement de saisons de clôture et les législations associées. Des stratégies pour diversifier la pêche marine ont aussi été proposées. Le Plan de développement quinquennal de 1990 pour les pêcheries marines met l'accent aussi sur la gestion de ressources appropriée afin de faire reculer les tendances associées à la surexploitation des ressources marines. Selon le plan, l'accent sera mis sur les pêcheries intérieures et la mariculture afin de réduire la pression sur les pêcheries. Les pêcheries intérieures, sous la forme de l'élevage de poissons en eau douce, ont pris leur essor sur les 10 dernières années avec une production qui s'est élevée de moins de 0,5 millions de livres en 1980 pour atteindre en 1989 plus de 6.0 millions de livres. Cependant, certains pisciculteurs en eau douce expérimentent déjà une concurrence sérieuse avec les agriculteurs pour l'usage de l'eau et, dans une moindre mesure, de la terre. Le Ministère de l'Agriculture est de l'avis que l'élevage en cage marine a technologiquement le potentiel d'être introduit en Jamaïque. La technologie a été développée avec réussite en Norvège et plusieurs pays dans la région utilisent actuellement la technologie expérimentalement. La technologie, si elle était utilisée en Jamaïque, pourrait réduire de façon significative la pression sur les pêcheries, ce qui rendrait la pêche plus économique et améliorerait les rendements aux pêcheurs. Certaines capacités techniques et institutionnelles existent déjà en Jamaïque qui pourraient soutenir le développement de l'élevage en cage marine. Le Département des Pêcheries a un personnel bien formé en aquaculture et pêcherie marine, dont certains qui sont directement responsables du succès de la pisciculture en eau douce. Par ailleurs, le Laboratoire Marin à l'Université des Antilles (UWI) mène des recherches sur les installations d'écloseries pour l'élevage en cage marine. Le Département des Pêcheries demandera la collaboration de l'unité marine à l'UWI qui pourra fournir des saumoneaux d'espèces marines sélectionnées pour la cage 1.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1993/rapport-1918.pdf
http://archimer.ifremer.fr/doc/00000/1918/

Résumé : It is about an article presenting the institute, its history, its presence and the projects it leads in New Caledonia. After a first part of general presentation of Ifremer a focus is placed on the strengthening of the presence of the institute in New Caledonia. 3 points are developed by L. Loubersac on the in-house organization, the strategy and examples of works realized within the framework of the buildind up of the lagoons integrated project. Then a spotlight is offered toward 3 projects: DEDUCTION 2 which aims at optimizing the performances of the shrimp aquaculture sector (T. Laugier), AMICAL which focuses on micro-algae aquaculture (L. Chim) and AMBIO centred on the monitoring and the definition of performance indicators for management of Marine Protected Areas and zones Registered on the World heritage (D. Pelletier). The synthesis of this article is realized by S. Chopot of the New Caledonia environment magazine.
Il s’agit d’un article présentant l’institut, son historique, sa présence et les projets qu’il mène en Nouvelle-Calédonie. Après une première partie de présentation générale de l’organisme un focus est placé sur le renforcement de la présence de l’Ifremer en Nouvelle-Calédonie. 3 questions sont posées à L. Loubersac sur l’organisation en interne, la stratégie et des exemples de travaux réalisés dans le cadre du chantier lagons. Puis un coup de projecteur est porté sur 3 projets : Déduction 2 qui vise à optimiser les performances de la filière crevetticole (T. Laugier), AMICAL qui se focalise sur la culture de micro-algues (L. Chim) et AMBIO axé sur le suivi et la définition d’indicateurs de performance des modes de gestion des Aires Marines protégées et des zones Inscrites au Patrimoine Mondial (D. Pelletier). La synthèse de cet article est réalisée par S. Chopot de la revue Environnement Nouvelle-Calédonie.
Environnement Nouvelle-Calédonie, 2013-05 , N. 20 , P. 60-89

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00200/31093/29501.pdf
http://archimer.ifremer.fr/doc/00200/31093/

Éditeur(s) : HAL CCSD Elsevier Masson
Résumé : International audience
The present study tested different sounds that could disturb eagle rays (Aetobatus ocellatus) during their foraging activities at Moorea, French Polynesia. Results showed that artificial white sound and single-frequency tones (40 Hz, 600 Hz or 1 kHz) did not have an effect on rays (at least 90% of rays continued to forage over sand), while playbacks of boat motor sound significantly disturbed rays during foraging activity (60% exhibited an escape behaviour). Overall, our study highlighted the negative effect of boat noises on the foraging activity of eagle rays. These noises produced by boat traffic could, however, have some positive effects for marine aquaculture if they could be used as a deterrent to repel the eagle rays, main predators of the pearl oysters.
Notre étude teste différents types de sons qui pourraient perturber les raies-aigles (Aetobatus ocellatus) pendant leur prise de nourriture dans le lagon de Moorea, en Polynésie française. Les résultats montrent que le bruit artificiel blanc ou des fréquences uniques (40 Hz, 600 Hz ou 1 kHz) n’ont aucun effet sur les raies (au moins 90 % des raies continuent de se nourrir dans le sable), tandis que l’enregistrement d’un moteur de bateau les perturbe significativement dans cette activité (60 % des individus ont un comportement de fuite). Notre étude met ainsi en évidence l’effet négatif des bruits anthropogéniques sur les activités de nourrissage des raies-aigles. Ces bruits produits par les bateaux pourraient néanmoins avoir un effet positif pour l’aquaculture marine s’ils pouvaient être utilisés comme répulsifs des raies, principaux prédateurs de l’huître perlière.
ISSN: 1631-0691

Droits : http://creativecommons.org/licenses/by-nc-nd/
hal-01297683
https://hal-univ-perp.archives-ouvertes.fr/hal-01297683
https://hal-univ-perp.archives-ouvertes.fr/hal-01297683/document
https://hal-univ-perp.archives-ouvertes.fr/hal-01297683/file/1-s2.0-S1631069116000020-main.pdf
DOI : 10.1016/j.crvi.2016.01.001

Éditeur(s) : Gauthier-Villars
Résumé : This review addresses the problem of recently introduced plants in the Mediterranean in order to analyse their vectors, the dispersal processes and the possible ecological and economic consequences. Ninety-five cases (94 macroscopic algae and one seagrass) are listed and discussed. Three major routes of access into the Mediterranean are indicated: shipping, the Suez canal and aqua-culture. The recent introduction of Caulerpa taxifolia along our coasts has called attention to a new potential source: aquaria. Among the successful acclimatizations, cold-temperate Pacific and Atlantic species remain confined to the north of the Mediterranean (Gulf of Lions, Adriatic), whereas some tropical or sub-tropical plants colonize large areas. Some introduced algae proliferate to the detriment of the indigenous Mediterranean vegetation. In contrast with some terrestrial introductions, no population crash has been observed in the Mediterranean, although some notable fluctuations seem to occur in coastal lagoons. From an economic point of view, the two activities most affected by this phenomenon are aquaculture and fishing. With the gradual disappearance of European frontiers, the worldwide development of marine cultures and the multiplication of giant Seaworlds, the transfer of live marine organisms will become routine and the risk of new introductions will considerably increase in the Mediterranean. Only international legislation, established by the countries of the littoral, will be able to control these problems.
Oceanologica Acta (0399-1784) (Gauthier-Villars), 1994 , Vol. 17 , N. 1 , P. 1-23

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00098/20879/18493.pdf
http://archimer.ifremer.fr/doc/00098/20879/

Éditeur(s) : EDP Sciences
Résumé : For centuries, several species of prawns and crabs have been raised from wild-caught juveniles in coastal brackish-water fish ponds in various countries of south east Asia. The Indonesian "tambaks" are well known examples of such traditional practices. In western countries, since the turn of the century, advances of marine biology and fast increase of marine fisheries enabled the development of large-scale production and release of larval stages of American and European lobsters in a fruitless attempt to restock natural populations. After the Second World War, the increasing demand for crustaceans in United States and Japan was satisfied by opening new prawn fisheries all over the world. A major breakthrough was achieved with the development of hatchery technologies for the penaeid prawn Penaeus japonicus (Hudinaga, 1942 in Japan) and the caridean prawn Macrobrachium rosenbergii (Ling, 1969 in Malaysia), which occurred during the first decades of the second half of this century. Together with the increasing market demand in developed countries for sea food, this led to a considerable interest of both public agencies and private investors in marine shrimp and prawn culture. In western countries, a large number of pioneering commercial ventures, often based on assumptions not scientifically founded, failed. Nevertheless, the aquaculture production of prawns mainly based on wild-caught juveniles increased in South-East Asia and Central America during the 1980s. This overall positive trend should not hide important failures which occurred at a local scale, such as the Taiwanese crisis of 1988 due principally to environmental degradation, resulting in severe disease problems and a near collapse of the farming activity. Following the early period of hatchery technology development, the major scientific achievements were related to food requirements and formulation of compound diets for larvae, juveniles and adults and to a better knowledge of diseases caused by bacteria and several viruses which have been identified from hatcheries and intensive farming ponds. Additional new technological advances have emerged from recent research in the fields of physiology (endocrinology) and genetics. By far, the major part of the world production of marine crustaceans relies on penaeid prawns and, to a lesser extent, on Macrobrachium species. However, some other species of marine crustaceans have potential for aquaculture. The economic aspects of marine crustacean aquaculture should be considered together with those of the fishing industry: market prices are rather similar, depending on the quality of the product. The balance between market demand and production is an important constraint which, in turn, establishes the success of prawn farming. Since the early 1980s, crustacean aquaculture has increased tremendously in both Asia and America: the world production for 1991 approximated 700,000 tons, with more than 600,000 tons from penaeid prawn culture.
Pendant des siècles, quelques espèces de crevettes et de crabes ont été élevées à partir d'individus juvéniles capturés dans le milieu naturel, dans des bassins à poissons d'eau saumâtre de différents pays d'Asie du Sud-Est. Les « tambaks » indonésiens sont des exemples bien connus de ces pratiques traditionnelles. Dans les pays occidentaux, depuis le début du siècle, les progrès réalisés en biologie marine et la croissance rapide des pêches maritimes ont permis le développement de la production à grande échelle de stades larvaires des homards européen et américain, dans une vaine tentative de reconstitution des stocks naturels. Après la Seconde Guerre mondiale, la demande croissante des Etats-Unis et du Japon a été satisfaite par l'ouverture de nouvelles pêcheries de crevettes dans l'océan mondial. Un progrès décisif a été réalisé avec la mise au point des techniques d'écloserie pour la crevette Pénaeidé Penaeus juponicus (Hudinaga, 1942 au Japon) et la crevette Caridé Macrobrachium rosenbergii (Ling, 1969 en Malaisie), qui sont apparues au cours des premières décennies de la seconde moitié de ce siècle. Parallèlement à la demande croissante du marché des pays développés pour les produits de la mer, ce résultat s'est traduit par un intérêt considérable porté à l'élevage des crevettes marines de la part des institutions de recherche et des investisseurs. Dans les pays occidentaux, un grand nombre de tentatives d'élevage commerciales, fondées sur des considérations non scientifiquement établies, ont échoué. Néanmoins, la production aquacole de crevettes reposant sur la capture d'animaux juvéniles dans la nature, s'est développée en Asie du Sud-Est et en Amérique Centrale au cours des années 1980. Cette tendance globalement positive ne doit pas dissimuler les faillites importantes qui se sont produites à l'échelle locale, comme la crise des élevages de Taiwan en 1988, causée principalement par une dégradation de l'environnement, entraînant l'apparition de problèmes pathologiques sévères et une disparition presque totale de l'activité d'élevage. Après la période pionnière du développement de la technologie d'écloserie, les principaux acquis scientifiques concernent les besoins alimentaires et la formulation d'aliments composés pour les larves, les jeunes et les adultes, et une meilleure connaissance des maladies bactériennes et virales qui interviennent dans les écloseries et les fermes d'élevage intensif. De nouveaux progrès techniques complémentaires ont vu le jour à la suite de recherches dans les domaines de la physiologie (endocrinologie) et de la génétique. De loin, la majeure partie de la production mondiale de Crustacés marins repose sur les crevettes Pénaeidés et, dans une moindre mesure, sur des espèces de Macrobrachium. Cependant, quelques autres espèces de Crustacés marins intéressent potentiellement l'aquaculture. Les aspects économiques de l'aquaculture de crustacés marins doivent être considérés avec ceux de l'industrie des pêches maritimes : les prix du marché sont à peu près les mêmes, et dépendent de la qualité du produit. Le rapport entre la demande du marché et la production est une contrainte importante qui à son tour, détermine les conditions du succès de l'élevage de crevettes. Depuis le début des années 1980, l'aquaculture de crustacés a augmenté considérablement en Asie et en Amérique : la production mondiale pour 1991 avoisine 700 000 tonnes, avec plus de 600 000 tonnes provenant des élevages de crevettes Pénaeidés.
Aquatic Living Resources (0990-7440) (EDP Sciences), 1993-10 , Vol. 6 , N. 4 , P. 319-329

Droits : IFREMER-Gauthier-Villars, 1993
http://archimer.ifremer.fr/doc/00190/30119/28587.pdf
DOI:10.1051/alr:1993033
http://archimer.ifremer.fr/doc/00190/30119/

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Sponges are a rich source for investigation of bioactive small molecules. They have been mostly investigated for the search of new pharmacological models or therapeutic agents for the treatment of human diseases. Micro-organisms can also represent a virulent pathogen for marine invertebrates such as sponges, which need to protect themselves against these microbes. Sponges' self defence mechanisms involving dialogue molecules thus represent a pertinent research track for potent anti-infective and anti-biofilm activities such as quorum sensing inhibitors (QSIs). The investigation of the QSI crude extract of Leucetta chagosensis Dendy, 1863 led to the isolation of three new alkaloids, isonaamine D, di-isonaamidine A and leucettamine D, along with the known isonaamine A and isonaamidine A. Isonaamidine A and isonaamine D were identified as inhibitors of the three quorum sensing pathways of Vibrio harveyi (CAI-1, AI-2 and harveyi auto inducer), but isonaamidine A displayed the strongest activity on AI-2 biosensor. Both compounds are new examples of natural QSIs of V. harveyi. These results outline the importance of these secondary metabolites for their producing organisms themselves in their natural environment, as well as the potential of the marine resource for aquaculture needs.
ISSN: 0266-8254

hal-01684926
https://hal.archives-ouvertes.fr/hal-01684926
DOI : 10.1111/lam.12461
PUBMED : 26138555

Éditeur(s) : Elsevier
Résumé : The gametogenic cycle and the reproductive effort of the blacklip pearl oyster, Pinctada margaritifera, cultivated in Takapoto lagoon were studied for a 1-year period (March 1997-April 1998) by bimonthly observations of gonadal sections, dry tissue weights and gonadal index in a population of pearl oyster composed of three age-groups. pearl oysters attained sexual maturity in the end of their first year (height approximate to 40 mm), implying that P. margaritifera is a late-maturing species in comparison with other Pteriidae. This species was also confirmed to be a marked protandrous successive hermaphrodite in culture, with 100 % of males at first maturity and 75 % in older pearl oyster (height > 120 mm). The general pattern of gametogenic activity, fairly synchronous in both sexes, was comparable with that of other tropical bivalves: reproduction occurs continuously throughout the year with a maximal activity during the warm season (November-May). No resting period was observed. Quantitative growth data showed that P. margaritifera exhibits an annual synchronised polymodal spawning pattern, with two spawning peaks in age-group I (height approximate to 70 mm) and five in age-groups II (height approximate to 100 mm) and III (height approximate to 120 mm). Spawning was sometimes incomplete, nevertheless a clear relationship between gamete production (P-R, g) and size (height H, mm) was obtained: P-R = 5.26 x 10(-7) H-2.91 (R-2 = 0.99, p < 0.05). Estimation of P-R was used to calculate the annual reproductive effort in P. margaritifera. Reproductive effort (%) was similar to those calculated for temperate species and showed a progressive increase with the age of pearl oyster, from 7 % in age-group I to 38 % in age-group III. This study showed that, in a fairly stable tropical environment such as the Takapoto lagoon, P. margaritifera is a multiple spawner, which uses an opportunistic reproductive strategy, allowing investment all year around, of any surplus energy into gamete production. Surplus energy is ensured by the high pumping rates developed by this non-symbiotic bivalve to succeed in low seston conditions. (C) 2000 Ifremer/Cnrs/Inra/Ird/Cemagref/Editions scientifiques et medicales Elsevier SAS.
Le cycle et l'effort de reproduction de l'huître perlière à lèvres noires, Pinctada margaritifera, cultivée dans le lagon de Takapoto, ont été étudiés sur une période annuelle (de mars 1997 à avril 1998), par un suivi bimensuel des stades de maturation et des indices gonadiques, sur une population en élevage composée de trois groupes d'âge (1, 2 et 3 ans). Cette étude a confirmé que P. margaritifera est une espèce qui se reproduit tardivement par rapport aux autres Ptériidés (elle atteint sa maturité sexuelle à la fin de sa première année, pour une hauteur approximative de 40 mm). Par ailleurs, elle présente, en élevage, une protandrie marquée (100 % de mâles à première maturité, 75 % pour des huîtres âgées de trois ans). Le schéma général de sa gamétogenèse, relativement synchrone dans les deux sexes, est comparable à celui des autres bivalves tropicaux : la reproduction est quasiment continue (aucune période de repos sexuel) avec une activité accrue en saison chaude (de novembre à mai). L'analyse des variations du poids de la gonade suggère l'existence de deux pics d'émission de gamètes chez les huîtres de un an et cinq pics chez les huîtres de 2 et 3 ans (cycle de reproduction de type polymodal). Bien que ces émissions de gamètes soient parfois incomplètes, une relation entre la production de gamètes (PR, en g) et la taille de l'huître perlière (hauteur, H, en mm) a été établie : PR = 5,26 x 10-7 H2,91 (R2 = 0,99, p < 0,05). Ces résultats ont permis de calculer l'effort de reproduction de P. margaritifera à Takapoto et sur un bilan annuel : il augmente avec l'âge de l'huître perlière de 7 % pour le groupe d'âge I à 38% pour le groupe d'âge III. Ces valeurs annuelles sont similaires à celles calculées chez les bivalves de milieux tempérés. Cette étude a donc montré que, dans un environnement tropical assez stable tel que celui du lagon de Takapoto, P. margaritifera présente une reproduction continue, avec plusieurs pics d'émission de gamètes par an. Cette stratégie « opportuniste » permet l'investissement, de tout surplus d'énergie en production de gamètes, tout au long de l'année. Malgré la faible concentration du milieu en nourriture, ces surplus d'énergie sont assurés par les fortes capacités de filtration développées par cette espèce tropicale non-symbiotique.
Aquatic Living Resources (0990-7440) (Elsevier), 2000 , Vol. 13 , N. 1 , P. 37-48

Droits : 2000 Ifremer/Cnrs/Inra/Ird/Cemagref/Éditions scientifiques et médicales Elsevier SAS
http://archimer.ifremer.fr/doc/2000/publication-1391.pdf
DOI:10.1016/S0990-7440(00)00135-2
http://archimer.ifremer.fr/doc/00000/1391/

Résumé : Ce rapport a pour objectifs d'apporter un éclairage sur la filière produits de la mer à la Réunion, de contribuer à en évaluer les perspectives d'évolution, d'estimer quelle sera la place future de l'aquaculture marine et d'offrir quelques pistes de réflexions. Il est réalisé à la demande du chef de projet IFREMER « Maîtrise de la Production et de la Valorisation de l'Ombrine ». Cependant, réalisé sur la base de rencontres avec les principaux acteurs de la filière, mais après seulement 3 jours de séjour sur place, ce rapport ne saurait être exhaustif. (voir annexe 1). Joint à ce rapport, une notice technique des différentes solutions de valorisation évoquées permettra de mieux évaluer la problématique. Enfin je tiens à remercier les différentes personnes rencontrées et qui m'ont pelmis de dresser ce bilan.

Droits : 2005 Ifremer
http://archimer.ifremer.fr/doc/00136/24742/22805.pdf
http://archimer.ifremer.fr/doc/00136/24742/

Éditeur(s) : Natl Acad Sciences
Résumé : The marine realm represents 70% of the surface of the biosphere and contains a rich variety of organisms, including more than 34 of the 36 living phyla, some of which are only found in the oceans. The number of marine species used by humans is growing at unprecedented rates, including the rapid domestication of marine species for aquaculture and the discovery of natural products and genes of medical and biotechnological interest in marine biota. The rapid growth in the human appropriation of marine genetic resources (MGRs), with over 18,000 natural products and 4,900 patents associated with genes of marine organisms, with the latter growing at 12% per year, demonstrates that the use of MGRs is no longer a vision but a growing source of biotechnological and business opportunities. The diversification of the use of marine living resources by humans calls for an urgent revision of the goals and policies of marine protected areas, to include the protection of MGRs and address emerging issues like biopiracy or benefit sharing. Specific challenges are the protection of these valuable resources in international waters, where no universally accepted legal framework exists to protect and regulate the exploitation of MGRs, and the unresolved issues on patenting components of marine life. Implementing steps toward the protection of MGRs is essential to ensure their sustainable use and to support the flow of future findings of medical and biotechnological interest.
Proceedings Of The National Academy Of Sciences Of The United States Of America (0027-8424) (Natl Acad Sciences), 2010-10 , Vol. 107 , N. 43 , P. 18318-18324

Droits : 2010 by the National Academy of Sciences
http://archimer.ifremer.fr/doc/00018/12897/9935.pdf
DOI:10.1073/pnas.0911897107
http://archimer.ifremer.fr/doc/00018/12897/

Éditeur(s) : Communication at the IIFET Conference Tromso 1998
Résumé : (not controled OCR) like most other caribbean islands, martinique suffers a reduction in fisheries resources and is now a net importer of seafood products since no major expansion of aquaculture production has been done. nevertheless, this island has numerous assets for marine aquaculture development : tropical clean waters, developed infrastructures and market channels, financial support for research, training and extension due to its tight political and economic connection with france. red drum is a subtropical fish introduced in martinique in 1985 from the south of usa for aquaculture purposes. from 1987 to 1993, ifremer worked on rearing techniques in martiniquan conditions. once the farming techniques were perfected, questions raised about red drum marketing potential and of economic viability of red drum farms in order to attract investments and entrepreneurs. that is the reason why a market analysis and a financial analysis have been carried out. the results of these studies indicate that martiniquan fish farming could be profitable, due to the rapid build-up of the facilities and to the sho rt production cycles. the good quality of infrastructures in martinique, the high purchase power of the population in comparison with most caribbean islands and the frequent air links with europe are important comparative advantages. the market analysis has revealed a good potential on the domestic market thanks to the development of the supermarkets, but has underlined the price constraint. for the french market too, production costs have to be lowered in order to compete on a market dominated by salmon.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1998/acte-2546.pdf
http://archimer.ifremer.fr/doc/00000/2546/

Éditeur(s) : Elsevier
Résumé : We studied the effects of a lactic acid bacterium, Pediococcus acidilactici (strain MA 18/5M, CNCM), as a dietary probiotic on growth performance and some nutritional and microbiological aspects of the shrimp Litopenaeus stylirostris. Experimental shrimp culture was carried out over 10 weeks, using floating cages of 14 m(2) each set in earthen ponds, in a New Caledonia farm affected by "Summer syndrome", a septicaemic vibriosis caused by Vibrio nigripulchritudo. The experiment design testing probiotic-coated pellets against control was replicated in two earthen ponds. High mortalities, characteristic of Summer syndrome, were observed during the first 2 weeks of the trial. The probiotic improved production in the treated cages from both ponds with increases in the survival rate (7% and 15% respectively) and final biomass (8% and 12% respectively). No differences were recorded among treatments on growth performances, but significant lower food conversion ratios were obtained with probiotic treatment. After 5 weeks of rearing, the Hepatosomatic Index and the adjusted dry weight of the digestive gland were significantly increased by 10% and by 9% respectively in shrimps treated with probiotic. In the meantime, the specific activities of alpha amylase and trypsin in the digestive gland showed a significant effect of the probiotic treatment with respective increases by 35% and 55%. The rise in total trypsin activity following morning feeding was also enhanced by the probiotic treatment (P < 0.001). The highest concentration of probiotic (between 10(4)-10(5) CFU g(-1) of fresh gut) in the shrimp gut was obtained 2 h after feeding. The concentration remained high for 4 h after feeding before decreasing until the next meal. Total bacterial counts on Marine agar and TCBS in the gut were significantly lowered by the probiotic treatment over the 10 weeks of the experiment. Additionally, during the first 2 weeks, prevalence and load of V nigripulchritudo strains in haemolymph was lower in animals fed with the probiotic diet. This study demonstrated, under pond conditions, that feeding shrimp with live terrestrial lactic acid bacteria can be an effective treatment for improving shrimp culture affected by vibriosis. (c) 2008 Elsevier B.V. All rights reserved.
Aquaculture (0044-8486) (Elsevier), 2008-03 , Vol. 275 , N. 1-4 , P. 182-193

Droits : 2008 Elsevier B.V. All rights reserved.
http://archimer.ifremer.fr/doc/2008/publication-4079.pdf
DOI:10.1016/j.aquaculture.2008.01.011
http://archimer.ifremer.fr/doc/00000/4079/

Résumé : The current legal regime governing marine farms reflects what French shellfish culture used to be: an artisanal, traditional and family activity. Even if this profession is of social importance, it has never really been taken into account in coastal management decisions. This is the reason why, if aquaculture must expand, the whole related legal regime has to be adapted to the new needs of a profession which is still trying to find itself. New links will develop with the responsible authorities. Conflicts of a new type will rise between the different coastal and marine space users. A rethinking of the standard public property regulations seems necessary.
Le régime juridique actuel des élevages marins est le reflet de ce qu'a été la conchyliculture en France : une activité artisanale, traditionnelle et familiale. Socialement importante, cette profession n'a cependant pas pesé lourd dans les choix d'aménagement du littoral. C'est pourquoi, si l'aquaculture doit prendre désormais de l'extension, c'est l'ensemble du régime juridique qui lui est applicable qu'il convient d'adapter aux besoins nouveaux d'une profession qui se cherche. Des rapports nouveaux vont naître avec 1'Administration de tutelle. Des conflits d'un type particulier risquent de surgir entre les divers usagers de l'espace marin et littoral. Un réaménagement des règles classiques de la domanialité publique semble inévitable. [OCR NON CONTRÔLE]

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1983/rapport-4804.PDF
http://archimer.ifremer.fr/doc/00000/4804/

Résumé : This report is presented by Chantal Cahu for obtaining accreditation to supervise research. Since 1981, her research activity has addressed the study of reproducers' nutrition and the young stages of development of marine organisms belonging to two different branch lines, crustaceans and fish. This work, performed in a base-lined research body, IFREMER, is placed within a more general programme of aquaculture development. Indeed, whatever species are at issue, the development of aquaculture in France, as at the global level, is based on the production of juveniles in hatcheries. My work has therefore more precisely the goal of acquiring knowledge about the nutritional needs, mechanisms of digestion and the development of these animals in order to improve the production of prawn post-larvae and fish alevin in the hatchery. This work took place in three main periods that appear in this report: - The study of reproducers' nutrition and its influence on the quality of the Penaeid prawn's eggs and larvae. My work has focused mainly on the effect of lipids and vitamins on the development of eggs and larvae. - The study of the ontogenesis of the digestive functions and the nutritional needs of sea fish larvae, with bass as the model. The goal was to determine the specific nutritional needs of the young stages by studying the implementation and regulation of pancreatic and intestinal digestive enzymes. - The study of the regulation of certain developmental genes by means of nutrients, so as to understand how these nutrients behave during ontogenesis, particularly during development of the skeleton.
Ce mémoire est présentée par Chantal Cahu pour pour l'obtention d'une habilitation a diriger des recherches. Depuis 1981, son activité de recherche concerne l'étude de la nutrition des reproducteurs et des jeunes stades de développement d'organismes marins appartenant à deux embranchements différents, les crustacés et les poissons. Ce travail réalisé dans un organisme de recherche finalisée, l'Ifremer, se situe dans un programme plus général de développement de l'aquaculture. En effet, quelles que soient les espèces en jeu, le développement de l'aquaculture en France comme au niveau mondial repose sur la production de juvéniles en écloserie. Mon travail a donc plus précisément pour objectif l'acquisition de connaissances sur les besoins nutritionnels, les mécanismes de digestion et le développement des ces animaux afin d'améliorer la production de post-larves de crevettes et d'alevins de poissons en écloserie. Ce travail s'est déroulé en trois grandes périodes qui apparaissent dans ce mémoire : - L'étude de la nutrition des reproducteurs et son influence sur la qualité des oeufs et des larves de crevettes Pénéides. Mon travail a essentiellement porté sur l'effet des lipides et des vitamines sur le développement des oeufs et des larves. - L'étude de l'ontogenèse des fonctions digestives et les besoins nutritionnels des larves de poissons marins, avec le bar comme modèle. Le but était de déterminer les besoins nutritionnels spécifiques des jeunes stades, en étudiant la mise en place et la régulation des enzymes digestives pancréatiques et intestinales. - L'étude de la régulation de certains gènes du développement par les nutriments, de façon à comprendre comment ces nutriments agissent lors de l'ontogenèse, notamment lors du développement du squelette.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2006/rapport-2086.pdf
http://archimer.ifremer.fr/doc/00000/2086/

Éditeur(s) : PSIC 11 - 11th Pacific Science Inter-Congress : Pacific Countries and their Ocean: Facing Local and Global Changes / 2nd Symposium on French Research in the Pacific. March 2 - 6, 2009 Tahiti, French Polynesia.
Résumé : In aquaculture, Artemia nauplii are commonly used as live prey; and represent 40 % of the total aquaculture feed demands in the early stages. However, the production of Brine shrimp is very unstable from one year to another and in the late 90’s, only 20 % of the world aquaculture need was covered. An insufficient offer leads to higher prices of the Artemia cysts and consequently, the price of shrimp juveniles from hatchery. In New Caledonia, marine aquaculture is mainly based on the blue shrimp Litopenaeus stylirostris. From Zoea 3 to 10 days old post-larvae (P10), the shrimp are mainly fed with live preys. Eleven kilos of Artemia cyst are necessary for producing one million of P10. From a sanitary point of view, Artemia can be a virus carrier and Vibrio population increase is often detected in the larval rearing tank the day after the feeding with live prey. Up to now, Brine shrimp are delivered in excess but with the cost and sanitary problems, Saint-Vincent laboratory has started some experiments in order to optimise the use of Artemia in shrimp larval rearing. The first tests were conducted to determine the effect of the Artemia quantity on the growth and the survival rate at different post-larval stages (P8-P11, P5-P8 and M3-P3). It was shown that four to twelve times fold Artemia was necessary for P8-P11 compared to M3-P3. And it was also noticed that the “optimized”quantity of live food at M3-P3 was twice lower than the recommended amount of the hatchery feeding protocol in New Caledonia. A better knowledge of the real feed requirement in the early life of the blue shrimp will be helpful to decrease the cysts quantities used in shrimp hatcheries but also the associated sanitary impact. And further, these results will give data for developing formulated diets which will replace the live prey and will increase the biosecurity and the sustainability of the production of the blue juvenile shrimp in New Caledonia.
En aquaculture, les nauplii d’Artemia sont largement utilisés comme proies vivantes et représentent près de 40 % des besoins en aliments pour la production des stades précoces. Cependant, l’approvisionnement en Artemia peut fluctuer de façon importante d’une année sur l’autre. Ainsi vers la fin des années 90, la demande mondiale a pu être satisfaite seulement à hauteur de 20%. Les années avec une offre insuffisante correspondent à des augmentations importantes du cours mondial des cystes d’artemia avec des répercussions sur le prix des animaux juvéniles produits en écloserie. En Nouvelle-Calédonie, l’aquaculture marine est principalement basée sur la crevette bleue Litopenaeus stylirostris. Les larves de cette espèce, à partir du stade Zoé 3, se nourrissent essentiellement de proies vivantes. Ainsi pour produire un million de Post-larves de 10 jours il faut compter 11 kilos de cystes d’Artemia. Outre le problème posé par le coût, les artemii peuvent également représenter un risque sanitaire pour l’écloserie. En effet certaines souches sont infectées par des virus qui peuvent contaminer les crevettes et de façon plus générale l’introduction des artemii dans le volume d’élevage larvaire s’accompagne le plus souvent d’une flambée de la flore vibrionacée. Jusqu’à présent, les Artemii étaient distribuées en excès cependant du fait de leur coût et des risques sanitaires, le laboratoire de St Vincent a débuté un travail pour optimiser leur utilisation en production larvaire de crevette. Ainsi, nos premières expérimentation sur l’effet de la dose en artemii sur le développement et la survie des larves de crevettes ont permis de déterminer les rations optimales pour les stades larvaires P8-P11, P5-P8 et M3-P3. Nous avons ainsi montré que la ration de proies vivantes était 4 à 12 fois plus importante à P8-P11 qu’à M3-P3. Par ailleurs la dose optimale déterminée au cours de nos expérimentations était pour les stades M3-P3 deux fois moins élevée que celle préconisée par le protocole actuel des écloseries commerciales de Nouvelle-Calédonie. Nous voyons ainsi, qu’une meilleure compréhension des besoins alimentaires de la crevette au cours de son développement permettra de diminuer de façon substantielle les proies vivantes utilisées ainsi que le risque sanitaire associé. A terme, ces travaux donneront des bases au développement d’aliments inertes en remplacement des proies vivantes et à la production durable, en conditions de biosécurité, des crevettes bleues juvéniles pour la filière Calédonienne

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00198/30877/29245.pdf
http://archimer.ifremer.fr/doc/00198/30877/