Ecoviability for small-scale fisheries in the context of food security constraints

This paper applies a stochastic viability approach to a tropical small-scale fishery, offering a theoretical and empirical example of ecosystem-based fishery management approach that accounts for food security. The model integrates multi-species, multi-fleet and uncertainty as well as profitability, food production, and demographic growth. It is calibrated over the period 2006–2010 using monthly catch and effort data from the French Guiana's coastal fishery, involving thirteen species and four fleets. Using projections at the horizon 2040, different management strategies and scenarios are compared from a viability viewpoint, thus accounting for biodiversity preservation, fleet profitability and food security. The analysis shows that under certain conditions, viable options can be identified which allow fishing intensity and production to be increased to respond to food security requirements but with minimum impacts on the marine resources.

RAIMOUEST : la pêcherie française de raies dans le golfe normand-breton

The landing ban of Raja undulata has raised misunderstanding for French fishermen, particularly for those fishing in the Norman‐Breton gulf (Southeast of ICES Division VIIe) where this species is very abundant. In this context, the RAIMOUEST project was launched as a professional and scientist partnership in order to enhance fisheries data on the main ray species caught in the Norman-Breton Gulf (Raja undulata, Raja brachyura, Raja clavata, Raja montagui and Raja microocellata). The French ray fisheries fleet was identified and a sample of fishermen involved in rays fishing was interviewed. Landings and effort data (logbooks), auctions sales and sampling at sea aboard professional fishing vessels were analysed. This working document presents the current results of this study. The French fleet concerned by ray fishing in the Normand-Breton Gulf in 2012 was composed of 289 vessels, mainly coastal trawlers/dredgers and small length size netters and longliners. R. undulata is the main ray species in this area. This species seems to form a local stock in the Normand-Breton Gulf with some continuity in the Eastern English Channel and the Western part of the Western English Channel. Three ways of analysis were used to provide an indicative level of R. undulata stock: French landings before 2009 were estimated at least at 300 tons in the Western English Channel (VIIe) and 160 tons in the Normand-Breton Gulf; sales at auctions of the Basse-Normandie fleet before 2009 were estimated at 235 tons in the western English Channel and 35 tons in the eastern English Channel (VIId); discards by the French bottom trawl fleet in ICES Division VIIe in 2012 and 2013 were estimated at 750 tons. Information on the spatial distribution of the other ray species in the English Channel was also provided. The coastal localisation of nursery for R. undulata and R. clavata was highlighted.

Does spatial distribution of fauna depend on algal belts on intertidal boulder fields of the French Basque coast ?

To determine good ecological status and conservation of the Sub-Marine area of the Bay of Biscay, the implementation of a new rocky intertidal habitats monitoring is needed. A protocol has been adapted from the Brittany protocol for the water body FRFC11 "Basque coast" for the two indicators "intertidal macroalgae" and "subtidal macroalgae" under the Water Framework Directive to qualify the ecological. However no protocol has been validated for fauna in front of meridional characters of the benthic communities. Investigations carried out on macroalgae communities on intertidal area in WFD framework, since 2008, constitute an important working basis. This is the aim of the Bigorno project (Intertidal Biodiversity of the south of the Bay of Biscay and Observation for New search and Monitoring for decision support), financed by the Agency of Marine Protected Areas and the Departmental Council. To implement knowledge, a sampling protocol has been used in 2015 on the boulder fields of Guéthary. This site is part of Natura 2000 area "rocky Basque coast and offshore extension "It constitutes also a Znieff site and restricted fishing area. The sampling strategy considers the heterogeneity of substrates and the presence of intertidal microhabitats. Two main habitats are present: "mediolittoral rock in exposed area habitat" and "boulder fields". Habitat "intertidal pools and permanent ponds" is also present but, it is not investigated. Sampling effort is of 353 quadrats of 0.1 m², drawn randomly according to a spatially stratified sampling plan, defined by habitat and algal belts. Taxa identification and enumeration are done on each quadrat. The objective of this work is to expose results from data collected during 2015 sampling program. The importance of characterizing benthic fauna communities spatial distribution belonging to the Basque coast according to algal belts defines during the WDF survey was highlighted. Concurrently, indicators of biodiversity were studied.

Inverse identification of the bending stiffness of a braided polyethylene twine subject to large deformation: application to the identification of the mesh opening rigidity of fishing nets.

The evaluation of the mesh opening stiffness of fishing nets is an important issue in assessing the selectivity of trawls. It appeared that a larger bending rigidity of twines decreases the mesh opening and could reduce the escapement of fish. Nevertheless, netting structure is complex. A netting is made up of braided twines made of polyethylene or polyamide. These twines are tied with non-symmetrical knots. Thus, these assemblies develop contact-friction interactions. Moreover, the netting can be subject to large deformation. In this study, we investigate the responses of netting samples to different types of solicitations. Samples are loaded and unloaded with creep and relaxation stages, with different boundary conditions. Then, two models have been developed: an analytical model and a finite element model. The last one was used to assess, with an inverse identification algorithm, the bending stiffness of twines. In this paper, experimental results and a model for netting structures made up of braided twines are presented. During dry forming of a composite, for example, the matrix is not present or not active, and relative sliding can occur between constitutive fibres. So an accurate modelling of the mechanical behaviour of fibrous material is necessary. This study offers experimental data which could permit to improve current models of contact-friction interactions [4], to validate models for large deformation analysis of fibrous materials [1] on a new experimental case, then to improve the evaluation of the mesh opening stiffness of a fishing net

PECHTRAD 2014 - Description et analyse des données de pêches traditionnelles à pied sur les platiers récifaux de la Réserve Nationale Marine de La Réunion.

This study aimed to build two databases, the first on the historic effort and catches of the traditional small-scale fisheries from 1999 till 2014, and the second one on the traditional management of fishing licenses. The first database allows for a synthetic analysis of the results obtained on the fishing activities of beach-seine, fishing rod and on octopuses, in terms of effort and catch per area and year. Technical and scientific supports were supplied implementing survey protocols and supervision of a student, both within the framework of the small-scale traditional fisheries. The study supported traditional fishermen with the mediation process for regulation revisions for the fishing activities in the MPA areas.