%0 Conference Proceedings
%9 ACTI : Communications avec actes dans un congrès international
%A Maufroy, A.
%A Bez, Nicolas
%A Kaplan, David
%A Delgado de Molina, A.
%A Murua, H.
%A Chassot, Emmanuel
%T How many Fish Aggregating Devices are currently drifting in the Indian Ocean ? Combining sources of information to provide a reliable estimate
%S 16ème groupe de travail sur les thons tropicaux
%C Victoria
%D 2014
%L fdi:010063302
%G ENG
%I CTOI
%K PECHE THONIERE ; TECHNIQUE DE PECHE ; DISPOSITIF DE CONCENTRATION DES POISSONS ; SENNE ; EFFORT DE PECHE ; VARIATION PLURIANNUELLE ; VARIATION MENSUELLE
%K STRATEGIE DE PECHE ; ETUDE D'IMPACT
%K OCEAN INDIEN
%N IOTC-2014-WPTT16-21
%P 25
%U https://www.documentation.ird.fr/hor/fdi:010063302
%> https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers15-01/010063302.pdf
%W Horizon (IRD)
%X Since the mid 1990s, drifting Fish Aggregating Devices (dFADS), artificial objects specifically designed to aggregate fish, have become an important mean of catching tropical tunas in the Indian Ocean for the purse seine fleet. In recent years, the massive deployments of dFADs as well as the massive use of tracking GPS and echosounder buoys on dFADs and natural floating objects (logs) have raised serious concerns for tropical tuna stocks but also regarding the possible modifications in ecosystem functioning. However, relatively little remains known on the modalities of dFAD and tracking buoy use by purse seiners. These knowledge gaps render difficult the evaluation of the impacts of fishing practices with dFADs and logs. For the first time, the three French fishing companies operating or having operated in the Indian Ocean provided the GPS buoy tracks of a large proportion of the dFADs and logs monitored by the French fleet. Here, we combine this new source of information with observations of dFADs and logs by observers aboard French and Spanish purse seiners, quarterly French fishing companies orders of buoys, and interviews with purse seine skippers conducted in the port of Victoria. This allows us to identify 4 dFAD and log seasons, to understand the strategies of fishers regarding dFAD and tracking GPS buoy deployment, to extrapolate the total number of dFADs and GPS buoys used by all purse seine fleets and to examine some of the impacts of dFAD use in the Indian Ocean. The results we obtain are a first step for a better assessment and management of the purse seine dFAD fishery.
%B GTTT : Groupe de Travail sur les Thons Tropicaux
%8 2014/11/15-19
%$ 040PECHE01