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Several sea cucumber species (Echinodermata: Holothuroidea) are fished, mostly for export of the dried product for Oriental consumers. Previous studies had analysed the historical trends at the world-scale until 2014. In the Western Indian Ocean (WIO) holothurian fisheries have a long history and several programmes have tried to ameliorate their management. Information has been recently gathered through a questionnaire and access to the most recent, yet unpublished available data (2015 to 2021) from different countries, through the evaluation of catches and/or processed product, present management systems, the imports of beche de mer and other products from Indian Ocean (IO) countries into the major market hub of Hong Kong SAR, and the Food and Agricuture Organisation (FAO) yearly statistics. The results are first presented for WIO countries, highlighting recent improvements in management. Imports from 16 WIO countries into the Hong Kong market (2017-2020 data) indicate the importance of the hub. The FAO world statistics are used to present the changes for the last few years, concentrating on the WIO countries. The recent trends show that demand for holothurians is still very high. Inconsistencies in the unit used in the reported statistics (fresh or dry weight) exist, and this needs to be addressed. The national data should be collected at the species level, to be able to follow the changes and the stock status. A regional approach is needed to encourage use of comparable management tools and follow future trends.

Since the 1980s, the Common Fisheries Policy (CFP) has shaped European fisheries. It has often been criticised for being too prescriptive and, above all, for failing to protect either fishermen or ecosystems. The last reform dates back to the early 2010 s and has led to a slight but slow improvement in the state of ecosystems. Given that the CFP is in the process of evaluation, a group of French fishery scientists set up an initiative to add to the debate on what should be retained, reinforced or added to a possible new reform. This initiative came 10 years after a previous manifesto that presented their vision for fisheries in Europe. Four major issues emerged from the current initiative: (1) a need for transparency and simplification in fisheries management, (2) a need for more consultation and dialogue between stakeholders, (3) the urgency of the situation in the Mediterranean Sea, and (4) the necessity of putting into practice all research developments for an ecosystem approach to fisheries. Compared to 10 years ago, the response of scientists shows that the focus is no longer on achieving the maximum sustainable yield, but rather on the following steps to protect ecosystems and fisheries. An ecosystem approach to fisheries remains indispensable for both ecosystems and fishing activities. To this end, scientists put forward numerous proposals to improve the CFP, acknowledging that the final solutions should emerge from consultation with stakeholders. Climate change, an issue raised much more than in the manifest, reinforces the need to act.

International audience; This paper investigates the dynamics of institutional development and co-management performance in small-scale fisheries. The study covers different contexts and spatial and temporal scales, for nine case studies in the South Pacific. In these cases, new co-management institutions were intentionally set up from 2008 to 2016 through fishery policy intervention to address over-exploitation problems of sea cucumber resources. This was carried out in a process of adaptive experimentation, based on a collaborative and problem-solving approach to governance, and a context-based vision of sustainability issues. In order to quantitatively and empirically assess change in governance within and between cases, a multidimensional analytical framework of governance performance is developed. A set of governance performance criteria is defined and the criteria are scored using data from an institutional diagnosis of the cases, throughout the research period. Ten out of eleven criteria were positively impacted by the co-management interventions. Three institutional development trajectories can be identified for the fishery co-management building process, involving a range of gradual and abrupt changes. Consolidation of the institutional changes achieved by the interventions is required to successfully develop the resilience of the fishing systems to multiple stresses. This empirical study provides a methodology for systematically assessing institutional dynamics in fisheries, and in particular the crafting and sustaining of co-management regimes in small-scale fisheries. The approach could potentially be applied to other complex social-ecological systems.

Holothuria (Microthele) fuscogilva (Cherbonnier, 1980), Holothuria sp. type "Pentard" and Holothuria (Microthele) nobilis (Selenka, 1867) are three tropical sea cucumber taxa that are heavily fished worldwide for the beche-de-mer trade market. In order to investigate the population genetic structure, diversity and connectivity of these taxa, 16, 19 and 25 microsatellite loci were isolated from H. fuscogilva, Holothuria sp. type "Pentard" and H. nobilis DNA libraries, respectively. These loci were tested on 94, 60 and eight individuals of the respective species, collected from the Seychelles. The number of alleles per locus ranged from 2 to 30. The observed heterozygosity ranged from 0.245 to 0.890 for H. fuscogilva and from 0.200 to 0.950 for Holothuria sp. type "Pentard", while the expected heterozygosity ranged from 0.231 to 0.952 and from 0.504 to 0.951, respectively. Several loci were at Hardy-Weinberg equilibrium and linkage disequilibrium was detected in only three pairs of loci. Cross-amplification was also tested and almost all loci (49 over 60) were polymorphic for at least two of the three studied taxa, showing high transferability among them. These loci represent useful tools for assessing genetic diversity and population structure of these three taxa in fishery areas, and therefore providing relevant knowledge for resource management.

International audience; During the last decade spatial patterns of industrial fisheries have been increasingly characterized using tracking technologies and machine learning analytical algorithms. In contrast, for small-scale fisheries, fishers’ behaviour for estimating and mapping fishing effort has only been anecdotally explored. Following a comparative approach, we conducted a boat tracking survey in a small-scale reef fishery in Madagascar and investigated the performance of a learning random forest algorithm and a speed threshold for estimating and mapping fishing effort. We monitored the movements of a sample of 31 traditional sailing fishing boats at around 45 s time interval using small GPS trackers. A total of 306 daily tracks were recorded among five gear types (beach seine, mosquito trawl net, gillnet, handline, and speargun). To ground-truth GPS location data, fishers’ behaviour was simultaneously recorded by a single on-board observer for 49 tracks. Typical, gear-specific track patterns were observed. Overall, the random forest model was found to be the most reliable, generic, and complex method for processing boat GPS tracks and detecting spatially-explicit fishing events regardless gear type. Predictions of mean fishing effort per trip showed that both methods reached from 89.4% to 97.0% accuracy across gear types. Our findings showed that boat tracking combined with on-board observation would improve the reliability of spatial fishing effort indicators in small-scale fisheries and contribute to more efficient management. Selection of the most appropriate GPS data processing method is dependent on local gear use, fishing effort indicators, and available analytical expertise.

International audience; The prickly redfish Thelenota ananas (Jaeger, 1833) is a widely distributed tropical sea cucumber. Populations of this species have been increasingly harvested throughout its distribution area in the Indo-Pacific region, which led to significant overexploitation issues. In order to investigate the genetic structure, diversity and connectivity of its populations, 42 microsatellite loci were isolated from a T. ananas microsatellite-enriched DNA library. These loci were characterized on 24 individuals collected from the Seychelles. The number of alleles per locus ranged from 3 to 22. The observed heterozygosity ranged from 0.083 to 0.952, while the expected heterozygosity ranged from 0.162 to 0.974. No linkage disequilibrium was detected among all loci and 20 loci (48%) were at Hardy–Weinberg equilibrium. These 42 loci represent useful tools for assessing genetic diversity, structure and gene flow among T. ananas populations, providing relevant knowledge for the management and conservation of those major commercial resources.

Measuring fish length is useful for exploring size structure of catches and fishing effects on marine resources. However manually measuring large numbers of individuals requires time-consuming manipulations, which are hardly operational in the context of tropical small-scale fisheries. To overcome this limitation, we developed a method to automatically measure total fish length using digital images and an analytical procedure using the ImageJ software. For testing this procedure, a total of 180 fishes (3 to 50 cm TL) from 19 families, presenting two color patterns and two caudal fin types, were obtained from small-scale fishers in southwestern Madagascar in 2018. We took standardized images of the fishes using a locally made, cost-effective camera-equipped device. The accuracy of fish size estimates and the time taken for measurements were compared across the ImageJ automatic procedure, manual measurements made on-screen using ImageJ, and measurements using an ichthyometer, the latter providing the reference fish length. The ImageJ automatic measurement procedure reached 98.4% accuracy while the measurement time was reduced by 57% and 40% compared to the measures using an ichthyometer and ImageJ on-screen tools, respectively. We conclude that the automatic measurement procedure provides very effective results for fish < 50 cm TL. This method is relevant for governmental, non-governmental, and research organizations that investigate size-related fishing and management impacts on fish community structure and dynamics.

The diverse characteristics, values, and importance of small-scale fisheries imply at least two key considerations. First, there is no tailor-made, one-size-fits-all solution to the problems and challenges facing small-scale fisheries; thus, policy and governance must be sensitive to the contexts. Second, the close relationship and interactivity between the natural and the social dimensions of small-scale fisheries suggests that knowledge and understanding about small-scale fisheries may need to transcend the boundaries of academic disciplines. These are the premises for research and activities conducted in the Too Big To Ignore (TBTI) – Global Partnership for Small-Scale Fisheries Research. Taking a transdisciplinary approach to research, training, and learning about small-scale fisheries can help address real-world problems and reveal opportunities to move towards pragmatic solutions. In this chapter, we discuss what transdisciplinarity involves, what the underlying principles are, and what makes it distinct from other perspectives. We argue that transdisciplinarity in small-scale fisheries requires institutional and academic innovation at local and national scales that facilitates interactive and transformative learning.

L’article interroge la disparité de la production artistique des hommes et des femmes, tentant de répondre par la psychanalyse à ce que chacun constate, que l’histoire consigne moins de grandes artistes que de grands artistes. L’examen des mécanismes de la jouissance apporte un élément d’explication. Une sorte de contre-exemple est fourni par l’étude du cas de la mathématicienne Emmy Noether, parvenue quant à elle à un degré élevé de la pensée abstraite.

Collecting spatial information on fisheries catch and effort is essential to understanding the spatial processes of exploited population dynamics and to manage heterogeneously distributed resources and uses. The use of fishers' knowledge through geographical information systems (GISs) is increasingly considered as a promising source of local information on small-scale coastal fisheries. In this paper we describe the first framework for mapping entire small-scale coastal fisheries using fishers' knowledge on catch size and fishing effort. Four mangrove and coral reef fisheries targeting invertebrates or finfish in New Caledonia (southwest Pacific) were mapped following a five-step framework: (i) stratified random sampling of regular fishers; (ii) collection of fishers' knowledge of fishing areas, fishing effort, and catch size through map-based interviews; (iii) data integration into a spatial geodatabase; (iv) statistical extrapolation of fisher data to the fishery scale; and (v) mapping of catch, effort, and catch per unit effort (CPUE) for each fishery using a GIS overlay procedure. We found evidence that fishers' knowledge supplied precise and accurate quantitative and spatial information on catch size, fishing effort and CPUE for entire fisheries. Fisheries maps captured the fine-scale spatial distribution of fishing activities in a variety of ways according to target taxa, gear type, and home ports. Applications include area-based marine conservation planning and fishery monitoring, management, and governance. This integrated framework can be generalized to a large range of data-poor coastal and inland small-scale fisheries.

In the Pacific, coastal communities have compensated for chronically low capacity of governments to manage fisheries by implementing local regulations in their marine tenure areas. In order to investigate the performance of community-based fisheries management (CBFM) in Vanuatu, trajectories and factors of change in CBFM systems since the 1990s were analysed. Focal group interviews were conducted in seven villages on Efate island in 2011 and supplemented by a review of supporting literature. Results reveal the increasing and excessive reliance of CBFM systems on external agencies that promoted overly complex management plans. Examination of trends in CBFM systems shows that community and national fishing rules that were highly acceptable by local societies were more likely to be enforced in the long run. In particular, the establishment of marine reserves was the most widespread and best enforced community rule for the purposes of conservation, ecotourism, and/or fisheries. Overall, the results challenge the current effectiveness of CBFM in achieving sustainability of reef fisheries in Vanuatu, and highlight the over-reliance on small marine reserves as a management tool. Community initiatives must be strengthened by new specific national regulations governing subsistence and commercial reef fisheries as part of a multi-scale co-management approach.

SUMMARYMany sea cucumber fisheries have dramatically declined worldwide due to rapid overexploitation and ineffective management. This study designed an innovative management strategy for small-scale, data-limited sea cucumber fisheries in Pacific Island countries. Firstly, a local quota-based comanagement system was implemented in New Caledonia to manage a small-scale sandfishHolothuria scabrafishery. A habitat map derived from high-resolution satellite imagery was used to stratify survey sampling and assess the harvestable stock biomass. The latter has been monitored as the reference biomass (RB) since 2008 and repeatedly used by the local fishers’ organization and Fisheries Department officers to set adaptive total allowable catches and regulations of fishing effort. Results showed the excellent performance of this fishery between 2008 and 2012, both biologically (167% increase in total stock biomass) and economically (146% increase in annual returns from catches). Secondly, the assessment of the RB was generalized to multispecies sea cucumber fisheries in Vanuatu in 2011 before the proposed lifting of a five-year national moratorium. Building upon these practical case studies in New Caledonia and Vanuatu, this paper outlines an operational framework to inform sea cucumber fisheries policy in these two countries and discusses the upscaling of the proposed management strategy.

Acoustic telemetry has been increasingly used for monitoring fish movements at different spatial and temporal scales. In this study, passive telemetry and fine-scale habitat data were integrated for the first time to investigate the relevance of community fishery reserves (CFRs) for managing reef fish resources. In Efate Island (Vanuatu), 38 thumbprint emperors Lethrinus harak (Lethrinidae) were tagged at 7 sites and tracked between April 2011 and February 2012 using an acoustic array of 16 receivers. The survey area extended over 11.3 km(2) of fringing reef in 3 coastal community tenures that included 3 small CFRs. Habitats were mapped using very high resolution satellite imagery and ground-truthing. Thirty fish were detected for up to 229 d (median = 153 d). Six geographical groups were identified among 21 resident fish. These groups showed strong fidelity to small sites (116 to 763 m) that were located in reserves and fished areas, across community tenures, and across 12 habitat types. Overall, 42 excursions were detected at several hundreds to thousands of meters from the fidelity sites along contiguous fringing reefs, across habitat types, and across boundaries of CFRs and community tenures. The estimated home range size of L. harak ranged from 116 to 3979 m (median: 763 m) and was highly varied within fish groups. We concluded that home range size and behavioral plasticity of L. harak limit the effectiveness of small individual CFRs for protecting this species. Networks of CFRs would be more effective but require management arrangements between neighbor communities.

In the Pacific, the protection of coral reef resources is often achieved through the implementation of village-based marine reserves (VBMRs). While substantial fisheries benefits are often reported, results of quantitative approaches are controversial for benthic macroinvertebrates, whose life history traits may cause low congruence with protective measures implemented at non-ecologically relevant scales. This study investigated the structural and behavioral responses of the exploited topshell Tectus niloticus within a very small (0.2 km(2)) VBMR in Vanuatu, south Pacific. The results of underwater surveys and a nine-month tagging experiment emphasized contrasted, scale-dependent responses. At the reserve scale, our results failed to demonstrate any positive effect of protection after three years of closure. In contrast, abundance, density and biomass increased more than ten-fold in the southern part of the reserve, along with significantly larger |(25%) individual sizes. The dispersal of tagged specimens was also consistently lower after 2, 4 and 9 months in the latter zone. Analyses of 17 substratum variables revealed a marked small-scale patchiness delineating contrasted benthic microhabitats, the distribution of which closely matched that of trochus. We advocate that i) VBMRs have inherently unequal ecological potentials for protecting and managing highly habitat-dependent species such as trochus; ii) 'success' or 'failure' is to a certain extent pre-determined by the trajectory of species-specific microhabitats, which may outreach protection effects. This has strong implications in the Pacific where the location and size of reserves primarily depends upon marine tenure, and communities have little flexibility in setting reserve boundaries.

Little is known about the effects of mud crabs population patterns on their exploitation. We used complementary approaches (experimental, fisher-based) to investigate how small-scale variations in density, size and sex-ratio related to the ecology of S. serrata may impact fishing practices in New Caledonia. Crabs were measured/sexed across 9 stations in contrasted mangrove systems between 2007 and 2009. Stations were described and classified in different kinds of mangrove forests (coastal, riverine, and estuarine); vegetation cover was qualitatively described at station scale. Annual catch was used as an indicator of fishing pressure. Middle-scale environmental factors (oceanic influence, vegetation cover) had significant contributions to crab density (GLM, 84.8% of variance), crab size and sex-ratio (

On the rural north-west coast of New Caledonia, the settlement of a major mining complex is expected to cause rapid and important socio-economic changes, resulting in significant effects on local fishing practices and their impact on resources. Fisher interviews were conducted in 2007 in this area to estimate fish catches, fishing yields and effort, to define a typology of informal fishing activities (including recreational, subsistence and benefit-aimed fishing), and to describe their spatial distribution. These results allowed the discussion of possible scenarios concerning the evolution of reef fish exploitation in a context of fast growing population and socio-economic changes. Local reef fisheries were essentially conducted through informal activities: 312 active boats were recorded and their catches reached 169 t/year whereas catches by professional fishers represented only 25 t/year with 4 boats. Practices and fishing yields were very diverse and linked to social, cultural and economic factors. Indigenous (Melanesian) fishers were mainly associated with subsistence and in some cases benefit-aimed activities (with informal commercialization), resulting in cost-benefit practices, important catches and the use of productive gears (gillnets). The fishers living in multi-cultural villages were mostly recreational, characterized by low yields and the use of less effective gears (spear gun, hand line). Fishing grounds were spatially structured according to these modern and traditional practices and their respective target biotopes. The main target families of reef fish were Lethrinidae, Acanthuridae and Mugilidae, the latter being mostly exploited by Melanesian fishers. The overall fishing pressure in the area (0.26 t/km2/year) was low compared to other countries in the Pacific. However, its spatial distribution showed that some areas were lightly exploited whereas others were close to overfishing. Results showed that the expected rise in fish demand may lead to unsustainable exploitation levels in the latter zones. The increase in the recreational fishing fleet may also result in additional fishing pressure as well as reef degradations. From a social point of view, the fast economic development of the area is likely to disturb the present informal organization of fisheries and to initiate conflicts over the use of space and resources. Such perspectives call for urgent management measures. This case study therefore provided insights into the complex structure of informal fisheries in insular territories in the Pacific and their possible evolution when confronted with socio-economic changes.

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.

International audience

Many Pacific countries face socio-economic changes, resulting in an increase in fishing pressure on reef fish resources. In coral reef environments, examining the ecological effects of fishing on fish assemblages is generally hampered by the lack of data for both in situ assemblages and fishing activities, and by the difficulty to account for natural variations in assemblages. The responses of fish assemblages to moderate fishing pressure were investigated in two sites of New Caledonia (South Pacific). Habitat structures and fish assemblages were described through in situ multiyear underwater visual surveys to account for spatial and temporal variability. A recent quantification of fishing catches and efforts allowed defining spatial gradients of fishing pressure. Linear models were used to test fishing effects on species richness, density, biomass, length and trophic structure of the whole assemblage, large species, target species, and different ecotrophic guilds. A significant decrease in most metrics was detected when fishing pressure increased. The results obtained for all-species fish metrics were confirmed for target species, large species, carnivores and corallivores trophic guilds and large individuals. This functional modelling approach accounted for the natural variability of local coral reef systems and allowed detecting effects of fishing, although fishing pressure was low to moderate in the surveyed sites. Our results suggest that further modelling development, including control sites, would allow precautionary indicators and strategies to be defined for the monitoring and management of reef fish resources. (C) 2014 Elsevier Ltd. All rights reserved.

Cet article synthétise les résultats d’un programme de recherche interdisciplinaire effectué sur la côte nord-ouest de la province Nord de la Nouvelle-Calédonie (Pacifique sud) de 2008 à 2011. Cette région fait face aux rapides changements urbains et économiques induits par la création d’un important complexe métallurgique. Ce projet industriel, porteur de développement économique, est aussi un projet politique emblématique du processus original de décolonisation négociée dans lequel la Nouvelle-Calédonie est engagée. Une démarche scientifique adaptative a été mise en place pour améliorer la connaissance de l’écosociosystème côtier et mieux gérer les usages littoraux, et les petites pêcheries en particulier. Cette démarche combinait trois approches complémentaires : recherche-action (s’appuyant sur les points de vue et les logiques des parties prenantes locales), interdisciplinarité (sciences biologiques, sociales et juridiques) et partenariat entre plusieurs institutions de recherche et de développement. Les résultats montrent que les principaux défis de gestion des usages littoraux sont fortement imbriqués et renvoient à des questions environnementales, sociales, culturelles aussi bien qu’économiques et politiques. Toutes les conditions pour la réussite d’une gestion participative ne sont pas actuellement réunies à l’échelle de la zone d’étude. Cependant, notre étude ouvre des pistes pour la promotion d’initiatives de gouvernance partagée, en se fondant sur des dynamiques locales existantes ou émergentes pouvant être élargies à d’autres échelles. Des orientations de politiques publiques sont aussi suggérées, incluant la promotion d’approches territoriales pour le développement local., This paper presents some results of an interdisciplinary research programme located on the northwest coast of New Caledonia from 2008 to 2011. This area faces rapid and significant urban and economic changes induced by an on-going major mining complex that is rooted within current political issues of the New Caledonian decolonisation process. An adaptive framework was set up to improve the knowledge on the coastal social ecological system and to better manage the uses of marine resources, including small-scale fisheries. This framework combined three complementary approaches : operational research (based on three interviewing surveys of local stakeholders), interdisciplinary studies (biological, social and law sciences) and partnership between research and development agencies. Results show that the main management challenges of the coastal uses are strongly embedded to cope with environmental, social, cultural as well as economic issues. All conditions for successful participative management are not currently met at the study area scale. However our study paves the way for action to promote initiatives of shared governance over the coastal area, building on existing or emerging local initiatives, and possibly scaling them up in the future. Directions for policy making are also suggested including territory approaches to local development.

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.

SUMMARYDespite the current expansion of community-based marine conservation initiatives in the Pacific, few studies have specifically addressed their ecological efficiency to restore or enhance reef invertebrate resources. This paper investigated the effects of two very small (< 0.05 km2) recent village-based marine reserves (tabu areas) located along the shallow fringing reef of Emau island, Vanuatu. Surveys focused on heavily harvested species (namely trochus, giant clams and green snails) and involved both experienced scientists and local villagers. Abundance, density and individual size data were collected by snorkelling along random transect belts located inside and outside the tabu areas, using simple PVC measuring tools specifically developed for participative monitoring. Habitat was assessed using a photographic method to quantitatively describe varied reef substrata. Resource recovery varied between the areas as a result of species-specific responses to contrasted reserve characteristics and local management practices. Fast-growing mobile Trochus niloticus exhibited strong positive abundance and size responses only within the older larger tabu area through the combined effects of protection from harvesting and translocation actions by local fishers. Similar trends were observed to a lesser extent for sessile slow-growing giant clams (Tridacna spp.), but these were not significant after four years of closure. Despite historical evidence of their presence in the area, surveys emphasized the severe population collapse of the heavily targeted green snail (Turbo marmoratus). Under certain conditions, very small-scale reserves, such as those implemented by village-based conservation initiatives, can rapidly and efficiently enhance local reef invertebrate resources. It is still unclear whether the changes are sufficient to restore critical levels of spawning biomass at larger scale and reverse the severe depletion of invertebrate resources occurring in Vanuatu.

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.

The use of scuba-based photo/video methods for characterizing coral reef habitats has gained increased popularity within the last decade, but few work examined the potentiality of surface photography to provide accurate, reliable habitat profiles in contrasted habitats. Photo transects were thus conducted by snorkeling in contrasted reef biotopes (reef flat, reef crest, sandy bottom) from the south-west lagoon of New Caledonia, to develop and test a "quick and clean" approach suitable for addressing monitoring as well as research-oriented programs. Pictures were taken by a snorkeler from the surface over twelve (20 x 1 m) reef crest/reef flat/soft bottoms transects using a standard 8 Mpixel digital-camera with underwater housing. Habitats were characterized from percent covers for 15 categories of local habitat variables related to sediment type and substrate coverage. Exhaustive area analyses using computer-assisted manual digitalizing were used to provide reliable habitat profiles from the digital pictures. Results were subsequently compared with surface estimates derived from random stratified point count techniques, for numbers of points comprised between I and 99 per m(2). Sampling-based randomization techniques allowed us to provide robust, reliable statistical estimates of accuracy and precision over 1000 randomized bootstrap replicates per transect. Results emphasized high accuracy and precision at transect scale whatever the reef biotopes considered, with maximum deviations from reference values of similar to 1 percent cover in almost all cases and associated variances From a practical point of view, using a 9 points/m(2) ratio clearly provided reliable, quantitative descriptions of our reef transects (maximal errors

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.