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International audience; Environmental education for children is one of the fundamental tools required to reverse the degradation of our environment and the biodiversity erosion. Currently coral reefs are part of the vulnerable ecosystems which are most threatened by human activities and climate change. Responding to these pressures demands decisions at multiple scales, based on solid knowledge of coral reefs but also on strengthened awareness to build adaptive management solutions. Here we evaluate the impact of an environmental awareness campaign for children using a teaching toolbox developed by scientists (MARECO "The Coral Reef In Our Hands"). To assess this impact before and after using the toolbox, we analyzed the evolution of children's representations of coral reefs through drawings. This study was carried out in New Caledonia, focusing on five elementary schools in different social and cultural contexts (urban, rural and coastal). Two hundred and forty-eight drawings were made by children. The drawings were analyzed quantitatively using multivariate statistical analyses which reveals a diversity of representations in children with diverse sociocultural profiles, but also between schools, emphasizing that relationships with nature and marine environment vary according to direct and indirect experiences related to reefs. Furthermore, our results pointed out relevant differences in coral reef representations before and after the use of MARECO, particularly regarding their knowledge of reef biodiversity associated with multicolored organisms and the connection of coral reef with environment, the number of colors being used as a proxy of this holistic vision developed by children. These results point out the performance of MARECO as a playful tool to transfer scientific knowledge to children. Coral reef conservation is intimately linked to an awareness in young generations of the environmental challenges of tomorrow. To be agents of change in a sustainable world, children must be engaged in a fun, rigorous, action-oriented and socially responsible learning process such as the ones developed in participatory approaches.

International audience; Coastal populations and tourism are growing worldwide. Consequently outdoor recreational activity is increasing and diversifying. While Marine Protected Areas (MPAs) are valuable for mitigating anthropogenic impacts, recreational uses are rarely monitored and studied, resulting in a lack of knowledge on users' practices, motivation and impacts. Based on boat counts and interview data collected in New Caledonia, we i) explored factors affecting user practices and motivations, ii) constructed fine-scale pressure indices covering activities and associated behaviors, and iii) assessed the relationships between user practices and site selection. User practices were found to depend on protection status, boat type and user characteristics. Pressure indices were higher within no-take MPAs, except for fishing. We found significant relationships between user practices and settings characteristics. In the context of increasing recreational uses, these results highlight options for managing such uses through settings management without jeopardizing the social acceptance of MPAs or the attainment of conservation goals.

La gestion durable des écosystèmes coralliens nécessite de disposer d'informations régulières concernant l'impact des pêcheries sur les ressources récifales et sur les écosystèmes dont elles dépendent. Les suivis intégrés des ressources, des habitats et des espèces associées qui visent à fournir ce type d'informations sont difficiles à mettre en oeuvre, car ils impliquent de nombreuses ressources humaines, techniques et financières. Face à ces problèmes, la participation de la société civile dans les programmes de suivi semble en mesure d'apporter des solutions. Dans le but de tester cette hypothèse, des méthodes de suivi participatif ont été mises en oeuvre afin de caractériser des pêcheries récifales sur trois socioécosystèmes contrastés : l'île de Moorea et l'atoll de Tikehau en Polynésie française, et le littoral de Tuléar à Madagascar. Les résultats de cette étude soulignent la pertinence de certains suivis participatifs pour fournir une vision écosystémique dans le cas de collecte de données ponctuelles et de large envergure, et leur intérêt moindre pour la collecte continue de données sur de longues échelles de temps. Dans tous les cas, une structure de coordination et l'implication de scientifiques s'avèrent primordiales pour assurer pérennité et fiabilité au système de suivi.

International audience; Deux sortes d'approches sont utilisées pour évaluer les effets des aires marines protégées (AMP) sur les pêcheries et la conservation biologique : (i) la modélisation statistique de données de terrain et (ii) la modélisation mathématique qui quantifie les conséquences des AMP sur la dynamique des populations, des peuplements et des pêcheries. Les modèles statistiques fournissent un diagnostic sur l'impact des AMP sur les écosystèmes et les ressources; ils sont également nécessaires pour mettre au point et évaluer des protocoles d'échantillonnage pour les programmes de suivi. Les modèles dynamiques permettent d'explorer les conséquences de différentes configurations de AMP et d'autres mesures de gestion. Nous faisons une brève revue bibliographique des applications de chacune de ces approches et identifions des indicateurs potentiels des effets des AMP, tels qu'ils peuvent être obtenus par chaque approche, dans le but de fournir un avis scientifique aux gestionnaires. Nous discutons ensuite des faiblesses méthodologiques qui nuisent à l'évaluation des effets des AMP et à la construction d'indicateurs appropriés et nous présentons des développements récents en la matière. Pour finir, nous proposons des pistes pour réconcilier les deux approches sur la base de leur complémentarité, afin d'en déduire des indicateurs adéquats pour aider à la prise de décisions. Dans cette optique, nous suggérons de plus que les gestionnaires de AMP soient associés dès le départ à la mise au point et à la construction des indicateurs.

International audience; Anthropogenic disturbances affect ecosystem structure and functioning. The quantification of their impacts on highly diverse and structurally complex ecosystems, such as coral reefs, is challenging. These communities are facing rising fishing pressure, particularly on Pacific Islands such as New Caledonia. The main objective was to quantify harvesting effects on invertebrate assemblages across two contrasting habitats (soft- and hard-bottom), by comparing communities in marine protected areas (MPAs) with non-MPAs using 10 biological and ecological traits. Patterns of trait composition were compared with those of species composition by non-metric multidimensional scaling and permutational analysis of variance analyses. Traits most responsible for differences between MPAs and non-MPAs were determined using SIMPER analysis, and predictions on shellfishing effects were discussed. A total of 248 species were recorded in hard-bottom communities, mainly characterized by mobile epifauna living on corals, crawling, and possessing a shell (molluscs) or a cuticle (crabs and echinoderms). Soft-bottom habitats contained 166 species, dominated by burrowing and sedentary species, especially shelled (largely bivalves) and worm-like organisms. Clear differences in species and trait composition between MPA and non-MPAs were highlighted in both habitats. Harvesting activities have community-wide effects that change the functional composition of invertebrate assemblages, in particular in terms of living habits and mobility. The observed shifts in benthic communities can affect the functioning of tropical coastal ecosystems and need to be included in small-scale fisheries management in poorly known tropical environments.

In coastal areas, demographic increase is likely to result in greater numbers of recreational users, with potential consequences on marine biodiversity. These effects may also occur within Marine Protected Areas (MPAs), which are popular with recreational users. Our analysis builds on data collected over a ten-year period during three year-round surveys to appraise changes in recreational boating activities in coral ecosystems. Results show that the number of boaters has greatly increased, particularly so within MPAs during weekends and the warm season, when peaks in boat numbers have become more frequent. We also observed that the number of anchored boats has increased over the period. These changes may be resulting in biophysical impacts that could be detrimental to conservation objectives in MPAs. This steady increase over time may cause changes in the spatial and temporal distribution of users and in their practices, thus highlighting the importance of monitoring recreational activities.

International audience

International audience; Despite the importance of invertebrate resources for Pacific coral reef islands, few studies have specifically addressed the effects of harvesting on invertebrate assemblages including targeted and non-targeted species. The impacts of recreational harvesting on reef and seagrass invertebrate assemblages in New Caledonia (South Pacific) are investigated by comparing communities in non-MPA and MPA areas. Sampling was done using a standard core method on seagrasses and by visual survey along belt transects on reefs. A total of 371 species were recorded, 174 on seagrasses and 254 on reefs, with 57 common species. Reef and seagrass invertebrate communities were very different in MPA and non-MPA areas. On both habitats, MPAs were identified as undisturbed areas while non-MPAs were defined as moderately disturbed with a predominance of small-sized and opportunistic species. Fishing not only affects target species but also non-target species through secondary effects. These results highlight the necessity of a community based approach for the conservation of resources in tropical poorly known environments.

Ten atolls of contrasting morphology and low human pressure were investigated in the Tuamotu Archipelago (French Polynesia) during the research program "Typatoll". This program produced large data sets about species richness of undisturbed fish assemblages and environmental data recorded at three spatial scales. Multivariate analyses defined six groups of transects of similar multi-scale environmental characteristics. Smoothed histograms (spectra) of species richness were plotted for each group of transect according to six size classes, six diet classes and six life-history classes of fish assemblages. The shape of spectra among groups of transects was then modelled through a single equation, determined by goodness-of-fit techniques. The height of each spectrum was then predicted by General Linear Model. Kolmogorov-Smirnov tests showed no significant difference between predicted and observed distributions of species richness. This two-phase model allowed predicting the diversity structure of undisturbed reef fish assemblages from few environmental data for the first time in the Pacific region. The resulting model will provide an efficient tool for detecting anthropogenic effects on the diversity of reef fish assemblages in atolls of the archipelago. This modelling approach could be adapted to provide a tool for the evaluation of variables affecting diversity of coral reef fish assemblages whatever the habitat they live in, and more generally the diversity of any other highly diversified tropical communities. (c) 2006 Elsevier B.V. All rights reserved.

Coastal fisheries in Pacific island countries are characterised by a strong predominance of catches for subsistence purposes which involves mainly finfish and is difficult to quantify. In 1997–1998, a consumer survey conducted in the Northern Province of New Caledonia (Southwest Pacific Ocean) made it possible to indirectly estimate subsistence fishing production. Catch from subsistence fishing did not result in a significant change of the exploitation potential. The catch composition of subsistence fishing differed significantly from commercial fishing, with a higher proportion of species less vulnerable to exploitation. Interpretation of the consumer typology highlighted the importance of factors such as ethnic group and geographical location in explaining eating habits and therefore, indirectly, fishing behaviours. These results suggest that this fish consumption survey could assist in the design of subsistence fisheries monitoring programmes.

The diversity of reef ecosystems, the multiplicity of reef resource uses and the breadth of the range of the island socio-cultural contexts concerned make coral reef fisheries (CRF) management in the South Pacific a complex task. The health and state of the targeted resources depend both on ecosystem characteristics (as determined by ecological and biological factors) and on fishing pressure, whose effects are only partly known. Increasing harvests from commercial and recreational fishing increasingly overlap with traditional Subsistence activity, creating an important CRF management challenge. This paper presents a new approach to CRF assessment and monitoring by providing a set of multidisciplinary indicators. The fisheries system is assessed from three different viewpoints: ecology of targeted populations, exploitation and the broader socio-econornic fishery context. The use of complementary indicators chosen from each of these fields could balance the chronic lack of human and financial resources for the management of these fisheries. We suggest the use of these indicators through an assessment grid or an indicator dashboard specifically adapted to given situations and management objectives determined through a participatory approach. The operational efficiency of this dashboard depends on i) dialogue between users, ii) the objectivity of the proposed monitoring, iii) the Visual transcription of divergent/convergent interests amongst stakeholders, and iv) stakeholder involvement in the decision-making process. The use and constraints of such a tool are described with reference to Ouvea atoll (New-Caledonia, South Pacific) for which an analysis of available indicators for assessing fisheries status is presented., La diversité des écosystèmes coralliens, la multiplicité des modalités d'exploitation de leurs ressources et l'hétérogénéité des contextes socio-culturels insulaires rendent complexe la gestion des pêcheries récifo-lagonaires du Pacifique sud. La santé et l'évolution de ces ressources dépendent, d'une part, des caractéristiques propres de l'écosystème (obéissant à des facteurs biologiques et écologiques) et, d'autre part, de la pression de pêche dont certains effets seulement sont établis. La pêche traditionnelle aux fins de subsistance est aujourd'hui concurrencée par des activités à visées commerciales et récréatives, qui accroissent les prélèvements et soulèvent de nouveaux enjeux de gestion. L'article propose une approche pour l'évaluation et le suivi de ces pêcheries basée sur un ensemble d'indicateurs pluridisciplinaires. Le système « Pêche » est analysé de trois points de vue complémentaires : l'écologie des peuplements exploités, l'exploitation halieutique sensu stricto et le contexte économique et social plus large des pêcheries. La mise en place d'indicateurs issus de ces trois domaines vise à compenser le manque chronique de moyens financiers et humains pour la gestion des pêcheries coralliennes des îles du Pacifique sud. Nous suggérons que leur utilisation s'effectue au travers d'une grille d'évaluation ou tableau de bord répondant à des situations précises et des objectifs de gestion définis lors d'une approche participative. La portée opérationnelle de ce tableau de bord de gestion de la pêche repose sur i) la concertation engagée entre les usagers, ii) l'objectivité du suivi préconisé, iii) la transcription visuelle des intérêts convergents et/ou divergents des acteurs, et iv) leur implication dans le processus de décision. Les modalités et contraintes d'application de cet outil sont décrites sur l'exemple de l'atoll d'Ouvéa (Nouvelle-Calédonie, Pacifique Sud), pour lequel une analyse des indicateurs disponibles pour décrire l'état des pêcheries a été réalisée.

Fishing tactics correspond to fishing practices at the scale of the fishing operation. In the case of mixed fisheries, they are defined as a combination of target species, gear, and fishing location, at a given time of the year. This paper proposes an approach to determine fishing tactics from the analysis of commercial catch and effort data. The approach is based on typologies of fishing operations involving multivariate descriptive methods like factorial analyses and classification techniques. The obtained types of fishing operations are considered as fishing tactics. The approach is applied to two contrasting examples, a small-scale Senegalese fishery and a Celtic Sea fishery that operates at a larger scale. Catch per species and fishing effort are computed per tactic. Results emphasize the importance of fishing location and seasonal effects for characterizing fishing tactics.

Value and monitoring of biodiversity on Moorea Island, French Polynesia : a methodological approach of terrestrial and marine ecosystems. The island of Moorea in French Polynesia is representative of a relatively well preserved small tropical oceanic island but both its terrestrial and marine ecosystems are currently under strong anthropogenic pressures. The terrestrial ecosystems are facing an increasing urbanization, and the destruction and modification of their natural habitats by cultivation and forestry plantations, accidental or intentional fires, and particularly by the invasion of alien plant and animal species. Coastal areas and reef ecosystems are threatened by shoreline artificialization, sedimentation due to soil erosion, increasing uses of marine and lagoon resources and frequency of coral bleaching events. A significant erosion of terrestrial and marine biodiversity is observed on the island since the last decades. In the context of the Land Management Plan (PGA) and Marine Area Management Plan (PGEM) recently set up in the island by local authorities, scientific surveys and inventories were made in 2006 in order to assess the status of terrestrial biodiversity (vascular plants) and marine biodiversity (reef fishes) and compare areas with different anthropogenic pressures. Studies conducted on the flora and the vegetation at low and middle elevation along altitudinal transects show that the plant invasion process is related to climatic and topographic factors, and species autoecology. The marine study aims to compare the protected areas with control areas in order to test the effectiveness of protection measures and to propose a streamlined monitoring protocol. A methodological study in both terrestrial and marine ecosystems was conducted in order to propose biodiversity indicators which are crucial for decision making in conservation and sustainable development of island biodiversity. We used Geographic Information System (GIS) as a fast and intuitive tool for mapping indicators and their variability. This methodological approach developed on the island of Moorea could be used as a model for other tropical islands., Moorea est une petite île océanique tropicale de la Polynésie française relativement bien préservée, mais dont les écosystèmes terrestres et marins sont actuellement soumis à de fortes pressions anthropiques. Le milieu terrestre est confronté à une urbanisation croissante, à la destruction ou à la modification des habitats naturels pour l’extension des cultures ou des plantations forestières, aux incendies volontaires ou accidentels, et particulièrement à l’invasion d’espèces végétales et animales introduites. Les zones côtières et les récifs coralliens sont menacés par de multiples perturbations telles que l’artificialisation des lignes de rivage, l’apport de sédiments dus à l’érosion des sols, l’augmentation des usages des ressources marines et lagonaires et de la fréquence des phénomènes de blanchissement du corail. Une érosion sensible de la biodiversité terrestre et marine de l’île est observée depuis les dernières décennies. Dans le cadre du Plan Général d’Aménagement (PGA) et du Plan de Gestion de l’Espace Maritime (PGEM) mis en place par les autorités locales, des inventaires scientifiques ont été réalisés en 2006 dans le but d’évaluer l’état de la biodiversité terrestre (plantes vasculaires) et marine (poissons récifaux) et de comparer des zones soumises à différentes perturbations. Les études réalisées sur la flore et la végétation de basse et moyenne altitude le long de transects altitudinaux montrent des processus d’invasion végétale différents en relation avec les facteurs climatiques, topographiques et autoécologiques des espèces. Les études en milieu marin visent à comparer des aires protégées à des aires témoins afin de suivre l’efficacité des mesures de gestion. La réflexion méthodologique menée parallèlement sur les deux écosystèmes a pour but d’illustrer différents indices de biodiversité nécessaires à la prise de décision en matière de conservation ou de développement durable de la biodiversité insulaire et de réaliser un état de référence pour établir un diagnostic sur l’état de la biodiversité. La représentation cartographique des indices à l’aide d’un SIG, illustrée dans cette étude avec la richesse spécifique terrestre et marine, permet une lecture intuitive et rapide de la variabilité de cet indice dont la restitution est basée sur une standardisation du nombre d’espèces. Cette approche méthodologique développée sur l’île de Moorea pourrait servir de modèle pour d’autres îles tropicales., Chevillotte Hervé,Meyer Jean-yves,Mellado-Forichon Tiscar,Florence Jacques,Emmanuelli Esther,Auberton-Habert Élisabeth,Galzin R.,Ferraris Jocelyne. Évaluation et suivi de la biodiversité dans l’île de Moorea, Polynésie française : approche méthodologique appliquée aux écosystèmes terrestres et marins. In: Revue d'Écologie (La Terre et La Vie), tome 69, n°3-4, 2014. pp. 267-284.

Invertebrates represent an essential component of coral reef ecosystems; they are ecologically important and a major resource, but their assemblages remain largely unknown, particularly on Pacific islands. Understanding their distribution and building predictive models of community composition as a function of environmental variables therefore constitutes a key issue for resource management. The goal of this study was to define and classify the main environmental factors influencing tropical invertebrate distributions in New Caledonian reef flats and to test the resulting predictive model. Invertebrate assemblages were sampled by visual counting during 2 years and 2 seasons, then coupled to different environmental conditions (habitat composition, hydrodynamics and sediment characteristics) and harvesting status (MPA vs. non-MPA and islets vs. coastal flats). Environmental conditions were described by a principal component analysis (PCA), and contributing variables were selected. Permutational analysis of variance (PERMANOVA) was used to test the effects of different factors (status, flat, year and season) on the invertebrate assemblage composition. Multivariate regression trees (MRT) were then used to hierarchically classify the effects of environmental and harvesting variables. MRT model explained at least 60% of the variation in structure of invertebrate communities. Results highlighted the influence of status (MPA vs. non-MPA) and location (islet vs. coastal flat), followed by habitat composition, organic matter content, hydrodynamics and sampling year. Predicted assemblages defined by indicator families were very different for each environment-exploitation scenario and correctly matched a calibration data matrix. Predictions from MRT including both environmental variables and harvesting pressure can be useful for management of invertebrates in coral reef environments.

In order to ensure the sustainable management of reef fisheries, it is necessary to obtain data about the impacts of these fisheries on both fish resources and the ecosystems that sustain them. Ecosystem - based surveys provide such information, but are difficult to implement because of high technical, financial and human resource requirements. In this regard participatory assessment methods have the potential to increase the amount of data collected at low cost, while taking advantage of local traditional ecological knowledge. In order to investigate the reef fishery of Toliara Bay, southwest Madagascar, we used participatory fish survey and interview data collected on site. These methods included: (i) monitoring of catch landings over six months by wholesale fish merchants, (ii) household surveys of fishing catch and effort, and fish consumption conducted by school children, and (iii) semi - structured interviews of reef users. The landings of 1,586 fishing trips were sampled between September 2006 and February 2007, 326 households were surveyed by trained school children in January 2007, and 70 reef users were interviewed in July/August 2006. Data collected by participants were compiled and compared to reference values when available, allowing an assessment of the sustainability of the reef fishery. The results of this study confirm the unsustainable nature of resource exploitation and underline the need for rapid management responses in order to reverse this trend. It also highlights the great potential of participatory assessment methods for gathering large amounts of relevant information on the status and evolution of the ecosystem upon which the fishery depends, while promoting education and awareness about the conservation and sustainable use of natural resources.Bien que les pêcheries récifales ne contribuent que marginalement aux captures de pêche mondiales, elles restent une source majeure de revenus et de protéines pour des millions de personnes, en particulier dans les pays en voie de développement. Afin de s’assurer de la bonne gestion de ces pêcheries, il est nécessaire de disposer d’informations sur l’état des ressources et des écosystèmes dont elles dépendent. Mener de telles études est d’autant plus compliqué que les pêcheries en milieu corallien portent sur un large éventail de stocks et d’espèces de poissons, concernent de nombreux pêcheurs et supposent diverses méthodes de captures, et empruntent un grand nombre de canaux de distribution. De plus, ces pêcheries sont souvent considérées de moindre valeur par les gouvernements qui leur octroient donc peu de moyens humains et financiers. Face à ces problèmes, l’implication de la société civile dans les programmes de suivi, appelé suivi participatif, semble en mesure d’apporter des solutions, d’autant que les suivis participatifs présentent l’avantage d’accroître le nombre de données collectées à moindre coût, tout en profitant des connaissances écologiques empiriques qui sont disponibles localement. Afin d’évaluer la pérennité de la pêcherie récifale de la baie de Toliara dans le sud ouest de Madagascar, des méthodes de suivi participatif ont été expérimentées. Ces méthodes consistent à mettre en oeuvre : (i) des suivis des débarquements pendant six mois impliquant des mareyeuses, (ii) des enquêtes auprès des ménages, réalisées par des écoliers préalablement formés, afin de recueillir des informations sur l’effort de pêche, les captures et la consommation de poisons, (iii) des entretiens semi - directifs avec des usagers du milieu marin. Ainsi, entre 2006 et 2007, 1586 sorties de pêche ont été échantillonnées, et 326 ménages et 70 usagers ont fait l’objet d’enquêtes. Les données collectées par les membres de la communauté locale ont été analysées afin d’évaluer la pérennité de la pêcherie dans la baie de Toliara. Les résultats de l’étude confirment une exploitation non pérenne et soulignent la nécessité de mettre en place des mesures de gestion afin d’inverser la tendance de détérioration des écosystèmes de la baie. Il ressort également de cette étude que l’implication de la société civile s’avère être pertinente pour recueillir des informations sur les pêcheries récifales à faible coût. En effet, de part le nombre, la qualité, la variété et la pertinence des informations produites, les suivis participatifs contribuent utilement à l’évaluation des pêcheries récifales. Cette expérience met également en évidence le fort potentiel des suivis participatifs à contribuer au renforcement des connaissances et des capacités des communautés locales dans le domaine de la gestion des ressources marines. Ainsi, face au difficile contexte socio - économique et politique qui prévaut actuellement à Madagascar, cette approche s’avère particulièrement prometteuse pour améliorer la gestion des pêcheries traditionnelles grâce à la production d’informations sur ces pêcheries et une plus grande implication des communautés locales dans le processus de gestion.Correction to: Madagascar Conservation & Development (2011) 6, 2: 60–67. http://dx.doi.org/10.4314/mcd.v6i2.4; published online 22 December 2011On p. 63, ‘mt/y’ should be metric ton per year and not million ton per year.Sentence should read “With the results of the household survey we were able to estimate a total production for the Toliara Bay fishery at 2,700 ± 436 metric tons per year (mt/y), and the annual yield at 14.2±2.3mt/y/km2.”

The gathering of invertebrates during low tides is a traditional activity across the Pacific islands, but it still remains poorly documented. Recreational invertebrate harvesting was investigated in 2008 and 2009 in the coastal/islet reef flats surrounding Noumea, the main urbanized area in New Caledonia (South Pacific). Human frequentation, harvesting effort, captures and their impacts on the density and size structure of the main targeted species were simultaneously quantified. Invertebrate harvesting was restricted to a 5-months winter period (April-August), depending mainly on low tides. Frequentation (similar to 10,000 persons year(-1) for an area of 324 ha) was a relevant proxy of harvesting pressure, with higher impacts on coastal flats compared to islet flats with respect to distance from city town and accessibility. On the whole, harvesters collected 8.4 +/- 0.7 t year(-1) of invertebrates (more than 60 species, mainly molluscs), with a mean of 8 harvesters ha(-1) over the year. Three clam species accounted for 50% of the total catch biomass (shell inclusive), with decreasing occurrences along the harvesting period emphasizing a reduction of the largest individuals. Harvesting-related disturbance mostly impacted the largest size classes, which constituted a minor (i.e. 3%) part of the reproductive adults. The 7-months non-harvesting period is likely to constitute a recovery period for the target species, with harvesting impacts on the natural populations less severe than initially expected.

Based on a pluridisciplinary research programme on New Caledonia's lagoon (2004-2008), this paper addresses economic, ecological and political issues in order to implement integrated coastal zone management (ICZM) in this French Pacific territory. The nickel mining industry constitutes the core of the re-balancing economic and social strategy between the Northern and Southern provinces. But major impacts on the coastal environment of metal-processing plants, harbours, and decades of mine exploitation have released a controversy. A short diachronic analysis suggests that such environmental concerns prompted the emergence of collective actions to among civil society, customary and institutional stakeholders. The inscription of New Caledonia lagoon and reef areas in the UNESCO World Heritage List in 2008 would be both an outcome and a catalyst of this on-going process. Looking beyond the reefs towards the mainland and watersheds for the construction of local socio-ecological systems, we assume that the current stakes could result in the initiation of ICZM in New Caledonia.

The coral reefs in New Caledonia have long been used by the local population for subsistence as well as commercial and recreational purposes. The impact of informal fisheries on reef ecosystems illustrated the idiosyncrasies of New Caledonian fisheries in the southwest Pacific. This paper compared informal fishery systems on the southwest coast (close to the capital and economic center of the country) and the northwest coast (where an industrial mining complex has been under development) of New Caledonia to analyze their spatial structure and characteristics. Four geosystems were defined. These depended on the natural, social and economical environments as well as management strategies. The way of life of the fishers proved to be a major factor in how the informal fishery systems were structured. Our observations suggested that ongoing socio-economic changes in New Caledonia have shaped informal fishing activities since the 1900s. The findings from this study validate the suitability of spatial approaches to coral reef fisheries and provide local stakeholders with original management clues for marine resources sustainability.

International audience; Bayesian Networks are useful tools for modeling interactions and predictions in social-ecological systems since they offer a robust theoretical framework towards risk and uncertainty management problems through the use of probabilities. Furthermore, this theory gives the possibility to combine expert knowledge and data. That's why they have been successfully used for helping resource-management decision-making process in numerous case studies. We propose to apply this approach in order to deal with the marine protected areas governance issue. A first model of Bayesian Network has already been developed from the French Polynesia case study concerning fisheries response to regulations in Moorea Island. This step allowed us to think about a more comprehensive model, which would encompass the ecological, economical and institutional components that underlie the understanding of the marine protected areas governance issue. Therefore we derived a second model from six case studies: three Mediterranean and three in French overseas. The first objective was to draw through the structure of the Bayesian Network a synthetic and comparative framework that represents the expert knowledge relative to the marine protected areas implementations and their consequences on the different components of the social-ecological system. The second objective is to simulate governance scenario for a particular case study-as the impacts of different regulation measures on the resources and biodiversity conservation of the ecosystem or on the satisfaction of users like fishermen or tourists-once the parameters of the model have been set up by using both database and expert judgment.

Due to the cost and time required for species identification, the taxonomic sufficiency approach has been developed in order to detect community response to a disturbance, using high taxonomic level without great loss of information. This concept has been widely applied to pollution monitoring studies but rarely to other forms of perturbations such as anthropogenic exploitation of marine resources. We applied this method both to soft-bottom (seagrasses) and hard-bottom (coralline) tropical invertebrate communities in New Caledonia, South Pacific. The objective was to test whether intermediate or high taxonomic levels (genus, family, class or phylum instead of species) are good descriptors of community patterns and changes in assemblages related to harvesting, by comparing harvested to non-harvested areas for the 2 habitats. We pooled species data into coarser taxonomic categories (from genus to phylum) and showed that matrices at different taxonomic resolutions were highly correlated, particularly for genus and family level for both habitats. Differences between harvested and non-harvested locations appeared to be clearly habitat-dependent; for soft habitats, genus and family resolution allowed the detection of changes between exploited and protected assemblages, while for hard habitats, the separation between harvested and non-harvested areas was less clear at high taxonomic level and required species-level identifications. These results suggest that the taxonomic sufficiency approach could be carefully applied to poorly known environments. Family level is a good descriptor of community composition for tropical reef invertebrates. Detecting changes due to anthropogenic exploitation requires different taxonomic resolutions depending on the considered habitat.

The normal inorganic contents of bone, brain, erythrocyte, heart, kidney cortex, kidney medulla, liver, lung, muscle and plasma from healthy Sprague Dawley rats were established by using a general method developed for inductively coupled plasma mass spectrometric multi-element determinations of most of the elements present in biological tissues. The most characteristic elemental pattern of each tissue was identified via a statistical multivariate analysis and a principal component analysis helped to elucidate the correlations between elements and tissues.

International audience; In many atolls of the South Pacific, a shift has occurred in the past couple of decades from traditional to more intensive fishing practices. Increasing fishing pressure on coral reefs raises the need for long-term studies to understand how fish communities react to fishing practice changes. The objective of this study was to analyse the variations of reef fish communities (in terms of species richness, diversity, density and structure) during a long time lapse at Tikehau atoll (Tuamotu archipelago, French Polynesia). The same eight lagoon pinnacles were sampled in 1987 and 2003 at 6 and 12 m depth. Quantitative data were collected by visual census techniques (UVC) on 50 m × 5 m belt transects. Analyses were conducted using a multiple spatial scale (depth, pinnacle and whole lagoon) approach with a particular attention on commercial species such as Scaridae (parrotfish), Acanthuridae (surgeonfish), Lutjanidae (snapper), Lethrinidae (emperor), Serranidae (grouper). Despite an increased sampling effort between 1987 and 2003, the mean species richness per transect decreased significantly from 26.2 ± 6.2 to 21.6 ± 9.6. The mean diversity varied similarly. A stronger decrease happened at pinnacles close to the village, where fish density also decreased. Conversely, fish density, species richness and diversity increased at pinnacles less visited by inhabitants. The community structure shifted from commercial species to small site-attached species e.g. Pomacentridae (damselfish), Ptereleotridae (dartfish) as fishing reduced the abundance (and biomass) of targeted stocks. We argue that these spatiotemporal variations resulted from a drastic change in fishing practices over the 16 years period, that shifted a sustainable fishery using traditional fish traps to an unbalanced, species-threatening, selective fishery. This study underlines the need for management and for the implementation of marine protected areas (including no-take zones) in order to protect the coral reef ecosystem and favor sustainable fisheries at Tikehau atoll.

Preuss, B., Pelletier, D., Wantiez, L., Letourneur, Y., Sarramégna, S., Kulbicki, M., Galzin, R., and Ferraris, J. 2009. Considering multiple-species attributes to understand better the effects of successive changes in protection status on a coral reef fish assemblage. – ICES Journal of Marine Science, 66: 170–179. 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 Aboré 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 defining 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.

L'influence des regimes hydrologique et thermique de la riviere aux Pins, un petit tributaire du fleuve Saint-Laurent, sur les migrations de fraie du Grand Brochet (Esox lucius) et sur l'avalaison des jeunes brochets de l'annee, a ete etudiee en situation naturelle en 1975, puis en situation de niveau controle en 1976. L'analyse factorielle des correspondances multiples a permis l'etude des covariations entre cinq variables biologiques et 12 variables hydrologiques et climatiques. Environ 70 % des adultes etaient deja presents dans la frayere au moment de l'installation des verveux, pourtant effectuee tot en saison. Le pic de fraie est survenu les 25 et 9 avril en 1975 et en 1976 (temperature moyenne de l'eau : 7–10 °C). L'avalaison des adultes fut hâtive en 1975; en 1976, elle fut tres importante immediatement apres la fraie, de faible intensite pendant le controle du niveau, et importante au moment de l'abandon du controle. Bien que modulee par l'influence des fortes temperatures, l'avalaison des geniteurs sensible etre favorisee par la baisse du niveau. A l'inverse, une augmentation du niveau suite a une pluie entraine une montaison et ralentit l'avalaison, meme tard en saison. Les premieres avalaisons de jeunes brochets de l'annee survinrent environ 30 jours apres le pic de la fraie, a une taille moyenne de 19 mm. A la fin juin 1975, 72 % des jeunes sejournaient encore dans la frayere, contre 27 % en 1976. L'abandon du controle du niveau, a compter de la fin mai, en 1976, provoqua l'avalaison massive des jeunes brochets. Ces resultats permettent de predire l'impact des manipulations du niveau de l'eau, en situation de frayere amenagee, sur le comportement des geniteurs et des jeunes de l'annee.

Despite the rapid rate of human-induced species losses, the relative influence of natural and anthropogenic factors on the functional diversity of species assemblages remains unknown for most ecosystems. A model was previously developed to predict the diversity structure of coral reef fish assemblages in 10 atolls of low human pressure and contrasting morphology of the Tuamotu Archipelago (French Polynesia). This existing model predicted smoothed histograms (spectra) of species richness according to size classes, diet classes and life-history classes of fish assemblages using a combination of environmental characteristics at different spatial scales. The present study applied the model to Tikehau, another atoll of the same archipelago where commercial fishing is practiced and where the same sampling strategy was reproduced. Significant differences appeared between predicted and observed species richness in several size, diet and life-history classes of fish assemblages in Tikehau. Two parameters which were not accounted for in the initial model, i.e. fishing pressure and atoll position within the archipelago, explained together 63% of variance in model residuals, >60% being explained by fishing pressure only. The respective effects of fishing and atoll position on the diversity of coral reef fish assemblages are discussed, with the potential of such modelling approach to assess the relative importance of factors affecting functional diversity within communities.

The objective of the present study was to evaluate the reliability of a modified version of the commercially available Biothesiometer, and to examine vibrotactile perception thresholds with respect to age and gender. A standardized protocol for measuring vibrotactile perception threshold was administered to 80 subjects, once a week over 4 weeks. Inter-session variability was stable (analysis of variance for repeated measures; P greater than 0.05) and correlations were high (Pearson's: 0.87 less than or equal to r less than or equal to 0.90; P less than or equal to 0.001). For sites on both hands and feet, there was a significant increase with age (0.19 less than or equal to r2 less than or equal to 0.52; P less than or equal to 0.001). Five factor analysis of variance model showed that vibrotactile perception threshold was significantly different with stimulus site, age category and gender; no differences were observed with alcohol consumption or smoking status. The findings indicate that the measurements from this device are highly reproducible and sensitive to expected threshold differences with age and gender. The authors attribute this to technical improvements of the original apparatus, rigid adherence to test protocol and maintenance of standard conditions. This type of instrument would be useful in assessing vibrotactile perception loss in occupational health studies.

Overexploitation of marine resources remains a problem worldwide. Many works advocate for the use of marine reserves as a central element of future stock management in a sustainable perspective. In the present paper, we address the influence of protected areas upon fisheries sustainability within an eco-systemic framework through a dynamic bio-economic model integrating a trophic web, catches and environmental uncertainties. The model is spatially implicit. The evaluation of the ecosystem is designed through the respect along time of constraints of both conservation and guaranteed captures. Using the mathematical concept of invariance kernel in a stochastic context, we define different MPA effects according to biodiversity catches or mixed points of view. Numerical simulations inspired from data of Abore coral reef reserve in New Caledonia illustrate the main concepts. In this case, it is pointed out how MPA conservation effect is not necessarily conflicting with MPA catches effect. it is shown that such a co-viability requires medium exploitation rate. Moreover, the climatic changes represented by rise in cyclonic events seem to reinforce these assertions. (C) 2007 Elsevier B.V. All rights reserved.

International audience; Few works have examined the relative contributions of habitat variables to the distribution of coral reef urchins. In the present study, the spatial distribution of two common urchin species (Diadema setosum and Echinometra mathaei) was studied in the fringing reefs of two urban bays in New Caledonia (South Pacific). Urchins were surveyed at 105 stations with contrasted habitat structure/anthropic disturbance levels; 32 environmental variables (water/sediment characteristics, reef structuring species) were considered. Moderate densities were generally observed at station scale (mean 0.5 individuals m(-2)). The combination of univariate and multivariate techniques highlighted patchy distributions for Diadema as well as Echinometra, with distinct species/habitat associations; environmental gradients occurring within the bays did not seem to influence the species patterns. For Diadema, the spatial variability was better explained by sediment type than by biotic cover; increasing densities occurred across habitats with larger sediment sizes and decreasing coral complexity/macrophytes cover. In contrast, the distribution of E. mathaei exhibited weak relationships with habitat variables. In coral reefs, small-scale heterogeneity may thus be responsible for most of urchins spatial variability.

International audience; This article aims to review 1) the major and most frequent human-induced physical disturbances and their consequences on coral reef habitats using a multi-scale approach, and 2) the scale-related indicators and conceptual aspects used to detect and measure the effects of these physical impacts. By physical disturbances, we mean direct perturbations that lead to the destruction/erosion of the carbonate framework. Human-induced direct physical disturbances are numerous from coastal development, tourism, harvesting, accidents and nuclear/weapon testing. Since methods for monitoring and measuring indicators are generally scale-implicit, coral reefs are first presented according to different ecological-spatial scales of organization, from colony to region (colony, reefscape, reef zone, whole reef, island and region). In this way, it is easier to link a couple {habitat, disturbance} to their potential indicators and to the descriptors they target. Three classes of descriptors, related to the response of the living component of coral reef ecosystem, are considered here: stony coral, reef fishes and the human uses. A synthesis of the different options for coral habitat assessments is proposed. We sort them according to their objectives (monitor, initial status or improvement of knowledge), their specificities (identification or not of a specific disturbances) and their scale of investigation (small, meso- or large scales). Usually, the majority of the indicators of human-induced disturbances are non-specific. They reveal that something is happening but not the actual causality and can only detect differences across time or space. A major weakness lies in the difficulty in deconvoluting the signals from a conjunction of stressors occurring at different scales. As such, a hierarchical concept of disturbances in coral reefs would be the next logical step to enhance our capabilities in monitoring and forecasting coral reefs status.

The present paper aims at identifying and assessing indicators of the effects of Marine Protected Areas (MPAs) in coral reef regions, based on a bibliography review in ecology, economics and social sciences. First the various effects Studied within each of these domains and the variables used to measure them were censused. Potential ecological indicators were assessed through their link with the question used (here termed "relevance") and their "effectiveness" which encompasses the issues of precision, accuracy and statistical power. Relevance and effectiveness were respectively measured by the frequency of use of each indicator and the proportion of significant results in the reviewed articles. For social and economic effects, the approach was not possible due to the low number of references: we thus discussed the issue of finding appropriate indicators for those fields. Results indicate: 1- the unbalance in literature between disciplines: 2- the need for protocols and methodologies which include controls in order to assess MPA effects: 3- an important proportion of ecological indicators with low effectiveness: 4- the large number of ecological effects still not studied or not demonstrated at present., Cet article vise à identifier des indicateurs de l'effet des aires marines protégées (AMP) en milieu corallien, sur la base d'une synthèse bibliographique dans les domaines écologiques, économiques et sociaux, et principalement en milieu corallien. Nous recensons d'abord les différents effets attendus des AMP pour chacun des domaines, et les variables retenues pour les étudier. Les indicateurs écologiques potentiels sont évalués au travers de leur lien avec l'effet étudié (ici appelé "pertinence") et de leur "efficacité" qui regroupe les notions de précision, justesse et puissance statistique. Pertinence et efficacité sont respectivement mesurées par la fréquence d'utilisation et la proportion de résultats significatifs trouvés dans les articles recensés. Pour les aspects économiques et sociaux, le faible nombre de références ne permet pas une approche comparable à celle utilisée pour les indicateurs écologiques, et nous discutons donc de la question de l'identification d'indicateurs, et suggérons quelques pistes de recherche. Les principales conclusions de ce travail sont: i) le décalage entre les nombres de publications entre disciplines; ii) la nécessité de protocoles et méthodologies incluant des situations de contrôle pour évaluer les effets des MPA; iii) la faible efficacité de nombreux indicateurs écologiques; et iv) le nombre élevé d'effets peu ou pas étudiés ou démontrés à l'heure actuelle.

Fishing pressure on reef fish stocks, in relation to exploitable biomass, is a useful parameter for fishery resource management but difficult to assess in subsistence fisheries. A methodology for indirect fishery output assessment in island environments is proposed based on estimates of consumption and the relevant seafood trade. Ouvea atoll in the South Pacific (Loyalty Islands, New Caledonia), where subsistence fishing is the main activity, was used as the IPF experimental site. A consumer survey of the islands' households was conducted in June 2000. The sampling plan was determined on the basis of data already available on the population concerned, making it possible to give quantitative and qualitative information on catches. Total catch is estimated to be 212 ty(-1) composed mainly of Lethrinidae, Serranidae and Gerreidae. Subsistence activity is the main source of supply for two-thirds of households. These results were validated by a survey carried out on fishers at the same time that confirms the reliability of fish Consumption as an indicator of reef fish catches. This study also showed that shoreline fishing remains the main activity in Ouvea: it's practised by 71% of households and provides almost 48% of total landings. A second stage was the identification of variables liable to influence consumption patterns: fishing practice (frequency and gear type), income, and household size seemed to be the main determining factors. These variables were integrated into a multi-dimensional analysis in order to define types Of Consumers. This consumption-based approach underlies a sampling strategy that could be a extrapolated to other small South Pacific islands. It involves advantages of various kinds-accuracy, reliability, and cost-effective implementation-that make it a powerful tool for monitoring island fishery development., La pression de pêche, reliée à la biomasse exploitable, est un paramètre utile pour la gestion des stocks de poissons récifaux, mais elle est difficile à évaluer pour la pêche de subsistance. Une méthodologie d'évaluation indirecte de la production halieutique est proposée, basée sur des estimations de consommation et d'échanges de produits de la mer. L'atoll d'Ouvéa dans le Pacifique sud (îles Loyauté, Nouvelle-Calédonie), où la pêche de subsistance est l'activité principale, a servi de site expérimental. Une enquête de consommation a été conduite chez les ménages de l'île en juin 2000. Le plan d'échantillonnage, défini à partir de données disponibles sur la population, a permis d'apporter des informations quantitatives et qualitatives sur les captures: la production totale, estimée à 212 t par an, se compose principalement de Lethrinidés, Serranidés et Gerréidés. La pêche de subsistance représente la principale source d'approvisionnement pour les deux tiers des foyers. Ces résultats ont été validés par une enquête conduite simultanément auprès des pêcheurs qui a confirmé la fiabilité de la consommation de poisson comme indicateur des captures de poissons récifaux. Cette étude de la production halieutique a également montré que la pêche littorale reste l'activité principale à Ouvéa: 71 % des ménages la pratiquent et elle représente près de 48 % des débarquements. Dans un second temps, l'étude a porté sur les variables susceptibles d'influencer la consommation de produits de la mer: la pratique de la pêche (fréquence et types d'engins utilisés), les revenus et la taille des ménages semblent être les facteurs déterminants. Ces variables ont été introduites dans une analyse multi-dimensionnelle afin de définir des types de consommateurs. Cette méthode basée sur la consommation de poisson décrit une stratégie d'échantillonnage qui pourrait être extrapolée à d'autres petites îles du Pacifique sud. Elle présente divers avantages (précision, fiabilité, facilité et rapidité de mise en œuvre) qui en font un outil performant pour suivre le développement des pêcheries insulaires.

Marine Protected Areas (MPA) are often contemplated as a tool for the sustainable management of exploited resources and ecosystem conservation. This paper proposes an approach to establish a statistical diagnostic of the effects of MPAs on fish assemblages, and define corresponding ecological indicators. This requires choosing relevant variables (abundance, diversity, demographic parameters..) and appropriate statistical methods. The study was based on data from the Abore reef Reserve in New Caledonia. Two sets of methods: 1-inferential linear models (ANOVA, GLM): 2- Partial Least Squares (PLS) methods of regression, were used to test the effects of this MPA. PLS enabled us to test simultaneously within a model, density, species richness, biomass and mean size variables of fish community to retain the most sensitive and relevant ones. Habitat variability was also taken into account in these models. Species were grouped according to several criteria: 1-feeding habit; 2- taxonomy; 3-mobility; 4-adult size; 5-demographic strategy. No significant effect of the opening of the Abore reef to fishing was found for mobility. Feeding habit was the only criterion for which the results from the inferential models and PLS showed a significant effect of reserve status for all variables. Species richness, density, and to a lesser extent mean size, were sensitive to the removal of reserve status. but not biomass. Results from ANOVA and PLS regression were consistent but the latter allows a more holistic approach as it integrates all variables within a single model., Les Aires Marines Protégées (AMP) sont de plus en plus considérées comme des mesures de gestion alternative permettant à la fois une gestion durable des ressources exploitées et la conservation des écosystèmes. Nous proposons une approche pour définir des indicateurs synthétiques et permettre un diagnostic statistique de l'effet des AMP sur les peuplements. Ce travail passe par le choix de variables pertinentes (abondance, richesse spécifique, paramètres démographiques, etc.) et de méthodes statistiques appropriées. Cette étude a été réalisée sur la réserve du récif Aboré en Nouvelle-Calédonie. Les données issues de deux campagnes scientifiques menées sur ce récif sont utilisées pour tester globalement l'effet des AMP grâce à des modèles linéaires inférentiels (ANOVA, GLM), et par des méthodes de régression PLS (Partial Least Squares). Ces dernières permettent de confronter dans un même modèle quatre variables (densité, richesse, biomasse et taille moyenne des poissons), afin de retenir les plus sensibles et les plus pertinentes pour l'évaluation de l'impact de la réserve. La variabilité de l'habitat est également prise en compte dans la modélisation. Les espèces sont regroupées selon plusieurs critères: 1- le régime alimentaire; 2- la taxonomie; 3- la mobilité; 4- des caractéristiques démographiques; 5- des caractéristiques de taille. Les espèces, quel que soit leur mobilité, n'apparaissent pas affectées par l'ouverture à la pêche du récif Aboré, qu'elles soient sédentaires ou très mobiles. Seul le critère trophique révèle un effet du changement de statut Réserve/Non Réserve pour toutes les variables, à la fois d'après les modèles inférentiels et les régressions PLS. Les résultats des modèles inférentiels et des régressions PLS montrent que la richesse spécifique et la densité sont les variables les plus sensibles à l'impact de l'ouverture à la pêche. La taille moyenne est également bien modélisée sur l'ensemble des résultats mais pas la biomasse. Les résultats d'ANOVA et de régression PLS sont cohérents mais la régression PLS permet d'intégrer toutes les variables dans un même modèle

The capacity of the Landsat 7 Enhanced Thematic Mapper Plus sensor to classify the shallow benthic ecosytems of New Caledonia (South Pacific) is tested using a novel unsupervised classification method. The classes are defined by using a set of multiple spectral decision rules based on the image spectral bands. A general model is applied to the entire Southwest lagoon (5500 km(2)) and tested on three representative sites: a section of the barrier reef, a cay reef flat rich in corals, and a cay reef flat rich in algae and seagrass beds. In the latter one, the classification results are compared with a locally optimized model, with aerial color photographs and extensive ground-truthed observations. Results show that a reconnaissance of the main benthic habitats in shallow areas (, Le but de cette étude est de tester la capacité des images Landsat 7 Enhanced Thematic Mapper Plus à discriminer les principales classes d’habitats benthiques rencontrées dans les parties peu profondes du système récifal et lagonaire de Nouvelle-Calédonie (Pacifique Sud). Une méthode originale de classification non-supervisée est proposée. Les habitats benthiques correspondent à une combinaison de plusieurs règles de décision établies à partir des bandes radiométriques Landsat. Cette modélisation statistique des habitats benthiques est appliquée au lagon sud-ouest de Nouvelle-Calédonie (5500 km2). Les résultats sont testés sur trois sites témoins contrastés: un platier de récif barrière, un platier d’îlot riche en corail et un platier d’îlot riche en herbiers/algueraies. Pour ce dernier, le résultat est comparé à celui d’un modèle optimisé, construit à échelle locale et validé à partir de photographies aériennes et d’observations de terrain. Les résultats montrent qu’une reconnaissance des différentes classes benthiques est possible pour des fonds peu profonds (< 5 m de profondeur), à l’échelle géomorphologique pour les structures récifales et à l’échelle des habitats pour les herbiers. Toutefois, les résultats bruts du modèle doivent être interprétés en fonction de critères spatiaux pour corriger les confusions entre certaines classes, notamment entre les pentes coralliennes et les herbiers denses.

This research consists of an attempt to provide algorithms that build abstracts on partition classes; these abstracts are formalized as probabilist symbolic objects and, when necessary, they extract from subsets, bodies of knowledge, in the form of scenarios, tactics or prototypes. An application is developped for the formalization of senegalese fishing tactics. Various problems with relative solutions, such as the unifying or discriminating of description balancing all along the treatment, are illustrated in this context.

Changes in olfactory function have been associated with workplace exposure to a variety of substances. In the workplace, smell can be particularly important, since it is commonly used to detect potentially hazardous situations or as an indicator of mask cartridge breakthrough. Sensitive quantitative measures of olfactory loss would be useful in epidemiological studies and workplace surveillance. The objective of the present study was to determine the reproducibility of an olfactory perception threshold test and variations with age, gender, and smoking status. The test was a standard olfactory kit (Olfactolab No. 11), including 18 serial dilutions of PM-carbinol, with an equal number of blanks. The forced choice method was used, with both tester and subject blinded as to which bottle contained the odorant. Olfactory perception threshold was recorded when the subject identified the same dilution three times. To assess reproducibility, testing was repeated four times over a period of 4 weeks, on the same weekday and the same time of day. Subjects (n = 63) ranged in age from 20 to 60 years (mean age: 39.7 +/- 12.5 years), 47.6% were women, 29.5% currently smoked, and 27.9% were former smokers. Results showed no inter-week differences in olfactory perception threshold (Analysis of variance for repeated measures: F = 0.59; p much greater than 0.05). Inter-class correlation for assessment of agreement of continuous variables was 0.76. Inter-week concordance of hyposmia showed fair to good agreement (0.55 greater than or equal to kappa less than or equal to 0.66). Three-way analysis of variance (ANOVA) revealed significant differences with respect to age category (F = 7.36; p less than 0.001) and current smoking status (F = 4.54; p less than 0.05), but not for gender (F = 2.32; p greater than 0.05). The multiple regression model with age and smoking as independent variables was highly significant (F = 13.03; p less than 0.001), explaining 28% of the variance; olfactory threshold increased 0.47 ds/year (t = 4.01; p less than 0.001) and 0.27 ds/cigarettes/day (t = 2.46; p less than 0.05). The findings of this study indicate that this test is reproducible and sensitive to expected changes with age and smoking status. It corresponds well to criteria for testing in the field and should be considered for studies characterizing olfactory functions and sensory loss among working populations.

The frequency of hypoxanthine phosphoribosyl transferase (HPRT) mutants among peripheral T-lymphocytes of radiotherapy technicians primarily exposed to 60Co was measured by the T-cell cloning method. Mutant frequencies of these technicians in 1984 and 1986 were significantly higher than those of physiotherapy technicians who worked in a neighboring service, and correlated significantly with thermoluminescence dosimeter readings recorded during the 6 mo preceding mutant frequency determination. Correlations decreased when related to dose recorded over longer time intervals. HPRT mutant frequency determination in peripheral lymphocytes is a good measure of recently received biologically effective radiation dose in an occupationally exposed population.

The application of clustering methods to ecological problems, which take place in a continuum, is sometimes puzzling because of lack of statistical methods for validating and comparing results. The aim of this paper is to propose an empirical way to compare the results from different hierarchical classifications with the original matrix of proximities. This method should permit us to evaluate the modifications of the initial structure and, finally, to understand the specificity of clustering methods.

We propose a statistical approach based on multivariate analysis and general linear models to test the consequences of removal of reserve status from the Abore Reef fish assemblage of the Abore Reef reserve, New Caledonia. Consequences on fish density were examined at the level of fish assemblage, accounting for habitat. Fish counts and habitat-related information were collected before and after the removal of reserve status, both inside and outside the reserve. Species groups were constructed on the basis of additional information on behavioural characteristics and taxonomy. The impact of the removal of reserve status was assessed by using 2 habitat proxies corresponding to 2 spatial scales and by considering several criteria for grouping species. Habitat appeared to be a determining factor in explaining density variations. Significant positive effects were found for several species groups such as macrocarnivores, piscivores, herbivores, Lethrinidae and Siganidae. A counterintuitive negative effect was observed for Acanthuridae. No significant differences between the area which remained closed to fishing and the area open to fishing were found for the other species groups. The approach allows for a synoptic diagnosis of the impact of changes in reserve status at the fish assemblage level. It could be used to develop and select potential indicators for monitoring such impacts on fish assemblages in coral reef ecosystems and in other contexts.

Coastal areas are complex socio-ecosystem where ecological, human and decisional compounds show multiple and reciprocal relationships. Because of the growth of population and tourism sector, coastal areas are permanently threatened through increase of recreational uses and diversification of related activities. To better understand coastal areas functioning, it is necessary to take into account uses and their management. Monitoring data over a ten years period revealed that recreational uses greatly increased especially within Marine Protecting Areas (MPA), during week-end days and warm season resulting to higher and more frequent frequentation peaks. While, practices within MPA are managed to decrease impacts, pressures associated with recreational uses are higher because of the concentration of users within MPA. As a consequence, ecological state decrease and social carrying capacity has been reached in several sites. Environmental quality is an important feature of satisfaction for recreational users but their activity lead to ecological impacts on fish, bird and habitat diversity of reef ecosystems. In addition, users. concentration and the diversification of sometimes conflicting practices decrease quality of experience of users and can lead to their displacement to other sites. As a consequence, pressures spread to less accessible sites, often not regulated and thus more threatened. Results allowed defining a model describing relationship between biodiversity, uses and management response. This model was used to test management scenarios, useful for integrated coastal area management and for identify knowledge gaps., Les espaces cotiers sont des socio-ecosystemes complexes ou les composantes ecologiques, humaines et decisionnelles presentent des relations multiples et reciproques. Du fait de la croissance demographique et du tourisme, ces espaces sont menaces en permanence par l.augmentation de l'intensite et de la diversite des usages recreatifs qui y sont pratiquees. Afin de mieux evaluer et gerer ces espaces, il est necessaire de prendre en compte explicitement les usages qui s.y pratiquent et les modalites d.intervention de la gestion. L.analyse de donnees de suivi de la frequentation sur une periode de 10 ans, ainsi que d.enquetes aupres des usagers a permis de montrer que le nombre d.usagers a particulierement augmente dans les AMP durant les week-ends et la saison estivale, avec aussi une frequence et une intensite accrues des pics de frequentation. Bien que les pratiques au sein des AMP soient moins impactantes car encadrees par la gestion, les pressions dues aux usages recreatifs y sont plus importantes du fait de la concentration des usagers dans ces espaces. On a constate que l.etat de sante de la biodiversite avait diminue et que la capacite de charge sociale etait atteinte dans certains espaces recreatifs. Par ailleurs, dans les AMP, la qualite environnementale apparait comme un facteur important de satisfaction pour les usagers, mais les impacts qu.ils engendrent entrainent une perte de la biodiversite au niveau des peuplements de poissons, des oiseaux et des habitats coralliens. De plus, la concentration des usagers et la diversification de pratiques parfois conflictuelles degradent la qualite de l.experience des usagers les incitant a se deplacer vers d.autres sites. En consequence les pressions se diffusent vers des sites moins accessibles, souvent moins reglementes et donc plus vulnerables. L.ensemble de ces resultats a permis de definir un modele decrivant les relations entre biodiversite, usages et reponse de gestion, et ce dans le but de tester des scenarios utiles a la gestion des espaces cotiers tout en identifiant les besoins en acquisition de connaissances.

The spatial distribution of human activities and decision-making support for the sustainable management of coral reef ecosystems: Recreational boat fishing in the south west lagoon of New-Caledonia. The coral reef resources in the New Caledonian lagoon are under growing pressure due to fishing activities. This is especially true in the south west where two thirds of the population and of private boats, whose owners are mainly recreational fishers, are located. In order to limit the pressure, it is necessary to manage the resources as well as the users in a sustainable manner, by developing knowledge on their fishing behaviours and their spatial dynamic. An historical approach exposes the evolution of the human communities’ fishing practices. The analysis of questionnaires targeting fishers from oct. 2004 to oct. 2005, enabled the study of their fishing behaviours influenced by social, economical, cultural or external factors and to determine a typology of the fishers and their fishing trips. Moreover, aerial flights were carried out throughout 2006 to assess the annual activity. These two methods were used to realize a spatial analysis in order to understand the way fishers create their own fishing territories, the spatial dynamic of the fishing activity in response to different criteria, and to assess the fishing pressures and impacts of boating and boat fishing activities. Fishers still consider that some areas in the lagoon are under threat in spite of the management of the lagoon environment. However, the way environmental management has been conceived has changed with the enlistment of the Caledonian coral reefs on the UNESCO world heritage list in 2008. The social acceptability of the management measures as well as the notion of heritage have been considered in order to propose a set of perspectives related to the management policies for resources and ecosystems.; Les écosystèmes récifo-lagonaires de la Nouvelle-Calédonie subissent une pression de pêche croissante surtout dans le sud-ouest, où se concentrent les deux tiers de la population et des bateaux de plaisance dont la majorité des propriétaires pratique la pêche. Pour limiter les pressions,il est nécessaire de gérer durablement la ressource et les usagers en développant la connaissance de leurs comportements de pêche et de leur dynamique spatiale. A travers une étude historique est exposée l’évolution des pêches pratiquées par les groupes humains. L’analyse de questionnaires proposés aux pêcheurs entre oct. 2004 et oct. 2005 a permis de réaliser une étude des comportements de pêche, influencés par des facteurs sociaux, économiques, culturels ou externes et de déterminer des typologies des pêcheurs et des sorties de pêche. Aux questionnaires s’ajoute une série de survols aériens réalisés en 2006 pour estimer l’activité annuelle. L’analyse spatiale réalisée à partir de ces méthodes a permis de comprendre les processus de territorialisation, de connaître la dynamique spatiale de l’activité de pêche selon différents critères, et d’estimer les pressions et impacts de la plaisance et de la pêche plaisancière. Les pêcheurs estiment qu’il existe des zones en danger dans le lagon, bien que la gestion de l’environnement ne soit pas récente. La conception de la réglementation a fortement évolué depuis l’inscription des récifs coralliens au patrimoine mondial de l’UNESCO en 2008. Enfin, une réflexion sur l’acceptabilité sociale des mesures de gestion et sur la notion de patrimoine conduit à proposer des perspectives pour aider la politique de gestion des ressources et des écosystèmes.

The spatial distribution of human activities and decision-making support for the sustainable management of coral reef ecosystems: Recreational boat fishing in the south west lagoon of New-Caledonia. The coral reef resources in the New Caledonian lagoon are under growing pressure due to fishing activities. This is especially true in the south west where two thirds of the population and of private boats, whose owners are mainly recreational fishers, are located. In order to limit the pressure, it is necessary to manage the resources as well as the users in a sustainable manner, by developing knowledge on their fishing behaviours and their spatial dynamic. An historical approach exposes the evolution of the human communities’ fishing practices. The analysis of questionnaires targeting fishers from oct. 2004 to oct. 2005, enabled the study of their fishing behaviours influenced by social, economical, cultural or external factors and to determine a typology of the fishers and their fishing trips. Moreover, aerial flights were carried out throughout 2006 to assess the annual activity. These two methods were used to realize a spatial analysis in order to understand the way fishers create their own fishing territories, the spatial dynamic of the fishing activity in response to different criteria, and to assess the fishing pressures and impacts of boating and boat fishing activities. Fishers still consider that some areas in the lagoon are under threat in spite of the management of the lagoon environment. However, the way environmental management has been conceived has changed with the enlistment of the Caledonian coral reefs on the UNESCO world heritage list in 2008. The social acceptability of the management measures as well as the notion of heritage have been considered in order to propose a set of perspectives related to the management policies for resources and ecosystems., Les écosystèmes récifo-lagonaires de la Nouvelle-Calédonie subissent une pression de pêche croissante surtout dans le sud-ouest, où se concentrent les deux tiers de la population et des bateaux de plaisance dont la majorité des propriétaires pratique la pêche. Pour limiter les pressions,il est nécessaire de gérer durablement la ressource et les usagers en développant la connaissance de leurs comportements de pêche et de leur dynamique spatiale. A travers une étude historique est exposée l’évolution des pêches pratiquées par les groupes humains. L’analyse de questionnaires proposés aux pêcheurs entre oct. 2004 et oct. 2005 a permis de réaliser une étude des comportements de pêche, influencés par des facteurs sociaux, économiques, culturels ou externes et de déterminer des typologies des pêcheurs et des sorties de pêche. Aux questionnaires s’ajoute une série de survols aériens réalisés en 2006 pour estimer l’activité annuelle. L’analyse spatiale réalisée à partir de ces méthodes a permis de comprendre les processus de territorialisation, de connaître la dynamique spatiale de l’activité de pêche selon différents critères, et d’estimer les pressions et impacts de la plaisance et de la pêche plaisancière. Les pêcheurs estiment qu’il existe des zones en danger dans le lagon, bien que la gestion de l’environnement ne soit pas récente. La conception de la réglementation a fortement évolué depuis l’inscription des récifs coralliens au patrimoine mondial de l’UNESCO en 2008. Enfin, une réflexion sur l’acceptabilité sociale des mesures de gestion et sur la notion de patrimoine conduit à proposer des perspectives pour aider la politique de gestion des ressources et des écosystèmes.

The people of the different South Pacific island countries have developed a strong link with the marine resources available to them. These resources represent one of their main sources of food and income. Every impact, natural or human-caused, on these resources, or their environment, can be detrimental to the sustainability of those resources. The development of management measures is a priority, even if little knowledge is known on these resources. The development of a mining complex in the north-western lagoon of New Caledonia will generate direct and indirect perturbations, at different scales, on the whole "socio-ecosystem" (which include several villages and local tribes).Among those perturbations, the increase of the population size will have one of the most damaging effects on the evolution of the finfish resources of the reef and lagoon. Scientific knowledge available on the functioning of the reef and lagoon ecosystem is fragmented and insufficient in terms of gaining a dynamic insight and a historical perspective.Therefore, the knowledge of the local people must be taken into account. The main purpose of this work is to set up a methodology in order to grasp this traditional knowledge. This methodology, drawing individual cognitive maps, is based on the representation that local stakeholders have on the functioning of the coral reef system. An ontology is set up to palliate the semantic heterogeneity encountered during the initial sketch of the maps and is also used to build synthetic group maps according to the different categories of stakeholders. It is used to classify the terms used during the drawing of the maps and has a hierarchical tree shape with a depth of 5 levels. By combining cognitive mapping and ontology, each map (individual and group map) can be represented in 5 different simplification levels. The representations of each stakeholder and category are compared against one another using two different approaches (Markoczy & Goldberg distance and centrality). They are also represented in a 2 dimensional space with MDS. The main results show a strong dichotomy between villagers and tribe inhabitants, both in the structure of the functioning of the coral reef system and the significance given to the different components of this system. These results provide a solid foundation, in terms of setting up communication measures, to develop an integrated management process for the coral reef lagoon environment and its associated resources., Les habitants des pays et états insulaires du Pacifique Sud ont développé une relation très étroite avec les ressources marines qui constituent une de leurs principales sources d'alimentation et de revenu. Tout impact sur le milieu ou les ressources elles-mêmes, qu'il soit d’origine naturelle ou anthropique, peut, directement ou non, remettre en cause la durabilité de ces ressources. La mise en place de mesures de gestion est indispensable, même si les connaissances sur celles-ci sont relativement limitées. La prochaine construction d'un complexe minier en bordure du lagon nord-ouest de Nouvelle-Calédonie va induire des perturbations directes et indirectes, à diverses échelles, sur l'ensemble "écosociosystème" adjacent qui inclut plusieurs villages et tribus locales. Parmi ces perturbations, l’augmentation de la population humaine constituera un des vecteurs de modifications les plus rapides sur les ressources halieutiques lagonaires. Si des connaissances "scientifiques" sur le fonctionnement de l'écosystème récifo-lagonaire existent, elles demeurent cependant parcellaires et ne permettent pas d'avoir une vision dynamique ni de recul temporel. Le savoir des acteurs locaux constitue alors une source de connaissances essentielle qu'il importe de prendre en compte. L'objectif de ce travail est de mettre en place une méthodologie permettant de récupérer ce savoir traditionnel, souvent empirique.Cette méthodologie s’appuie sur la représentation de la perception des acteurs locaux du fonctionnement du système récifo-lagonaire par le tracé de cartes cognitives individuelles. Une ontologie est mise en place pour pallier l'hétérogénéité sémantique rencontrée lors du tracé initial des cartes et pour établir des cartes de synthèse par catégorie d'acteurs. Elle classe l'ensemble des termes utilisés lors du tracé des cartes et se présente sous la forme d'un arbre hiérarchique sur 5 rangs. La combinaison de la cartographie cognitive et de l'ontologie permet de représenter chaque carte (individuelle ou de synthèse) selon 5 niveaux de simplification. Les représentations de chaque acteur et catégorie d'acteurs sont comparées deux à deux selon deux approches (distance de Markoczy & Goldberg et centralité) et sont projetées sur un espace plan à l'aide d'un MDS. Les principaux résultats mettent en évidence une dichotomie marquée entre les acteurs des villages et ceux de la tribu tant au niveau de la structure du fonctionnement du système récifolagonaire que de l'importance relative accordée aux différents éléments constitutifs de ce système. L'ensemble des ces résultats constitue une base solide pour la mise en place de mesures de communication en vue d'une approche intégrée de la gestion de l’environnement et des ressources récifo-lagonaires.