Line of action:

Status:

Execution date:

General Objective:

Improve selectivity and reduce the direct impact of trawl gear.

Specific objectives:

1. To develop a trawl gear that is less impactful and more selective than the current ones for fishing on the platform bottoms of the SCI Canal de Menorca open to this fishery.

2. To estimate the survival rates and recovery capacity of algae and macro-invertebrates, which are part of the discards, after being trawled and to identify factors that affect their mortality, to increase their survival.

3. To prepare a manual of good fishing practices and a custody agreement for the trawl fleet that fishes on these seabeds.

4. Dissemination of the project and its results.

5. Efficiently manage the resources provided to achieve the objectives.

Once the project is finished, we can present the results obtained from each of the main actions developed:

1. As for the main results of the design and evaluation of an experimental trawl gear for fishing on the SCI platform Canal de Menorca , it can be stated that these have been satisfactory:

• With the modification of the lead rope, a reduction of up to 50% of the discards of algae and benthic macro-invertebrates, mainly rhodoliths, sea squirts and echinoderms, is obtained.

• Semi-pelagic doors, reducing the length of winds and mallets reduce their direct impact and reduce fuel consumption, as a result of lower tensile strength, so costs are also reduced.

• These efficiency gains are achieved without reducing catches of commercial species.

• The reduction of discards is achieved with trawls adapted to avoid these catches. This is shown by the density of the rhodoliths estimated in the study area, from epibenthic sled samples, which turned out to be three orders of magnitude higher than the catch rates obtained with bottom trawling gear during the experimental fishing campaigns.

• In addition to this maintenance of commercial performance, there is also a reduction in operating costs, as a result of the reduction in fuel consumption.

2. Regarding the estimation of the survival and recovery capacity rates of discarded algae (rhodoliths) and macro-invertebrates (sponges, echinoderms and sea squirts), it is concluded that these rates increase with the introduction of small changes in the triage and management of discards. Some images of the experiments are attached.

• Rhodoliths: The ability to photosynthesize and recover depends on exposure to direct sunlight. The structure of S. fruticulosus allows survival under conditions of high solar irradiation and dehydration.

• Sponges: Sponges with large, singular oscules have a higher capacity than sponges with a complex tertiary structure. S. domuncula and T. aurantium have a 100% survival rate to trawling, even under direct sun, while T. muricata does not survive.

• Crustaceans: the species D. arrosor seems to have a high capacity for survival. Direct sun exposure causes dehydration and overheating, which can lead to death after 1 hour.

• Echinoderms: Rotdolith-dwelling brittle disease suffer high mortality rates after exposure to direct sun.

• Ascidians: P. mamillata has a survivability in conditions of high humidity and low irradiation. It did not present damage due to dragging.

3. As regards the improvement of the fishing practices of the platform trawling fleet in the SCI Canal de Menorca, The Manual of Good Fishing Practices and Marine Stewardship Agreement, aimed at the professional artisanal fishing sector that fishes in the Menorca Channel and the rest of the bottom trawling fleet of the Balearic Islands, with a detailed explanation of the project -experiments, results obtained and conclusions- and a list of actions to be carried out by the vessels, both in the modification of their gear and in the treatment of the catches on board and their subsequent return to the sea. The proposed Marine Stewardship Agreement would set out a commitment to implement this protocol.

The dissemination of the project and its results has been carried out through two informative workshops.

• The presentation of the project, Projecte DRAGÓ: Millora de l’eficiència ecològica de la pesca d’arrossegament al SCI Canal de Menorca, was organized by the Balearic Federation of Fishermen’s Guilds (FBCP) and the IEO on March 30, 2019 at the Casa del Mar in Palma. Representatives of all the fishermen’s guilds of the Balearic Islands attended, as well as the Director General of Fisheries and the Mediterranean of the Government of the Balearic Islands. The background and objectives of the project and the planned activities were presented.

• The day of presentation of the results of the project, DRAGÓ Project. 1. Design and evaluation of experimental trailing art: 1.1. Assembly. 1.2. Experimental fishing campaign, was held on 22 February 2020 at the Casa del Mar in Palma. 38 people attended, including representatives and patrons of the fishermen’s guilds of the Balearic Islands. Also in attendance were the Director General of Fisheries and the Mediterranean Sea of the Government of the Balearic Islands, the WWF Fisheries Coordinator, representatives of the University of Cádiz and the Fishermen’s Guild of Palamós, who presented the results of the DiscardLife and TipoArt projects, which correspond to the 2018 call of the Pleamar Programme.

In addition, the actions and results have been published on the website of the Federation and the COB of the IEO and its social networks. Press releases were also prepared with the presentation of the project, its main activities and results, as well as interviews with radio, TV, written press and a brochure presenting the project, DRAGÓ: Innovation of Trawling in the Menorca Channel.

In relation to publications, the problem of the impact of fishing and fishing discards, as well as possible solutions, has been included in seminars and university master’s courses, and the article Discards reduction of non commercial benthic species from a simple net modification or Technical measures to reduce the impact of bottom trawling on red algae seabeds has been published in the journal Fisheries Research, written by María Teresa Farriols, Francesc Ordines and Enric Massutí. In addition, two publications have been made in the magazine Ruta Pesquera & Naval:

• J.M. Llodrà, I. Ruiz-Jarabo and E. Massutí.- 2019. Improvement of the ecological efficiency of trawling in the SCI Canal de Menorca. Ruta Pesquera, 135:1.

• J.M. Llodrà, C. Ros, A. Garau, I. Ruiz-Jarabo, J.M. Mancera, E. Massutí, M.T. Farriols, F. Ordinas and B. Guijarro.- 2020. Results of the DRAGÓ project: Technical and innovative measures to improve the ecological efficiency of trawling in the SCI Canal de Menorca. Ruta Pesquera, 139: 18-19.