Bycatch species composition over time by tuna purse-seine fishery in the eastern tropical Atlantic Ocean.

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Bycatch of the European purse-seine tuna fishery in the Atlantic Ocean for the period 2010-2016

This paper presents an update for the period 2010-2016 of the bycatch estimations for the European tuna purse seine fishery operating in the Atlantic Ocean. Bycatch data were collected by observers onboard. Observer coverage increased progressively from 15 trips in 2010, to 114 and 107 trips in 2015 and 2016 respectively. Bycatch data, as collected by the observers, were stratified by quarter and fishing mode (free school and floating object sets). The ratio of total to observed catches of the target species (skipjack, bigeye and yellowfin tunas) in each stratum was then used as raising factor. The average of the annual total bycatch estimated for the studied period was 9,515 t. Tunas (neritic tunas and small size tunas) represent the major part of the bycatch, followed by fin fish, sharks, billfishes, rays and turtles.En prens

Factors driving patterns and trends in strandings of small cetaceans

The incidence of cetacean strandings is expected to depend on a combination of factors, including the dis- tribution and abundance of the cetaceans, their prey, and causes of mortality (e.g. natural, fishery bycatch), as well as currents and winds which affect whether carcasses reach the shore. We investigated spatiotemporal patterns and trends in the numbers of strandings of three species of small cetacean in Galicia (NW Spain) and their relationships with meteoro- logical, oceanographic, prey abundance and fishing-related variables, aiming to disentangle the relationship that may exist between these factors, cetacean abundance and mor- tality off the coast. Strandings of 1166 common dolphins (Delphinus delphis), 118 bottlenose dolphins (Tursiops truncatus) and 90 harbour porpoises (Phocoena phocoena) during 2000–2013 were analysed. Generalised additive and generalised additive-mixed model results showed that the variables which best explained the pattern of strandings of the three cetacean species were those related with local ocean meteorology (strength and direction of the North– South component of the winds and the number of days with South-West winds) and the winter North Atlantic Oscil- lation Index. There were no significant relationships with indices of fishing effort or landings. Only bottlenose dolphin showed possible fluctuations in local abundance over the study period. There was no evidence of long-term trends in number of strandings in any of the species and their abun- dances were, therefore, considered to have been relatively stable during the study period.Versión del editor2,01

Local market of the tropical purse seine fishery: update and perspective for its assessment in Abidjan

Part of the tuna catch of purse seiners, not sold to the canneries, is landed with other bycatch species towards another commercial flow. This local flow better known as “Faux poisson” is an important socio-cultural and economic market for Ivory Coast and neighboring countries. Yet, Faux poisson catches landed to this local market increased this last decade since the development of FAD fishing in the mid-nineties. Regarding major tuna species, the catch landed in the local market is mainly composed of small individuals which are not accounted for in the species composition and in catch at size estimates from conventional sampling. Because of the difficulties of the data collection this portion of tropical tuna landing is ignored in the stock assessment models. The need of improve knowledge is so of prime importance to better assess the sustainability of the fishery and the ecosystem. The document presents the main results of recent research on local market flow landed in Abidjan by purse seiners French fleet in the eastern Atlantic. Data collection improvement and perspective for species composition assessment and catch at size are further discusse

Utilization and trade of "faux poisson" landed in Abidjan

Le document présente les principaux résultats de la recherche sur le commerce et l'utilisation des prises accessoires retenues et débarquées à Abidjan par les senneurs dans l'Atlantique Est. D'après cette recherche, les prises accessoires retenues contribuent grandement à la sécurité alimentaire et elles revêtent une grande importance sociale et économique pour la population locale. Une partie des poissons débarqués à Abidjan par les senneurs a été acheminée vers d'autres villes de Côte d'Ivoire et également vers d'autres pays, comme le Burkina Faso et le Mali. Les thonidés demeurant à Abidjan ont été majoritairement (95%) utilisés par les industries du garba (garbadromes). Ces garbadromes ont créé entre six et neuf mille postes de travail et sont accessibles à pratiquement toute la population, notamment les jeunes. Toutefois, la durabilité de ce commerce ne peut pas être effective sans une politique de rétention appropriée que l'ICCAT devrait adopter en ce qui concerne les thonidés tropicaux de l'océan Atlantique

Local market of the tropical purse seine fishery: update and perspective for its assessment in Abidjan

Part of the tuna catch of purse seiners, not sold to the canneries, is landed with other bycatch species towards another commercial flow. This local flow better known as “Faux poisson” is an important socio-cultural and economic market for Ivory Coast and neighboring countries. Yet, Faux poisson catches landed to this local market increased this last decade since the development of FAD fishing in the mid-nineties. Regarding major tuna species, the catch landed in the local market is mainly composed of small individuals which are not accounted for in the species composition and in catch at size estimates from conventional sampling. Because of the difficulties of the data collection this portion of tropical tuna landing is ignored in the stock assessment models. The need of improve knowledge is so of prime importance to better assess the sustainability of the fishery and the ecosystem. The document presents the main results of recent research on local market flow landed in Abidjan by purse seiners French fleet in the eastern Atlantic. Data collection improvement and perspective for species composition assessment and catch at size are further discusse

Targeting bigger schools can reduce ecosystem impacts of fisheries

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