An initial review of previous studies on reducing turtle bycatch in surface longline fisheries enabled a robust experimental design to be developed for three at-sea experiments using commercial fishing vessels. A survey of fishermen was also undertaken in the three areas to investigate the current gears in use, fishermen’s perception of the problem of turtle bycatch and their attitude to potential changes in gear and bait type.

The fishing experiments tested the effects of different hook and bait types on both turtle and swordfish catch rates. The trials were conducted in collaboration with the fishing industry in the following fisheries:

• Greek longline fishery in the eastern Mediterranean, between 30 May and 8 September 2007;
• Spanish longline fishery in the western Mediterranean, between 11 July and 17 September 2007;
• Spanish distant water longline fishery in the south-east Atlantic Ocean, between 28 February and 4 April 2007.

Experimental fishing was carried out by one vessel in each region with observers collecting data on turtle bycatch and on target species weights and catch rates. Two longlines were set each day, one with squid bait and one with mackerel bait, and each with alternating hook types of J hooks, 0o offset 16/0 circle hooks and 10o offset 18/0 circle hooks. 35 trials (70 lines) were carried out in the Atlantic, and 60 trials in each of the eastern and western Mediterranean fisheries.

Duración: Octubre 2006 – Febrero 2008

Participantes:

• MRAG Ltd
• AZTI-Tecnalia
• Lamans S.A.