Discards

Today I have to tell the readers of Murcia that I know they are  not, in fact, reading us. Acho, this is unbelievable... and now we can move on to discuss discards. When a boat goes fishing, certain species are preferred, and we call them target species. But unless the boat prefers schooling pelagic species, the chances are that the boat will catch its target species plus other species that have the misfortune to share their living space with commercial species. Sometimes these non-target species also have commercial value, and we call that fraction of the catch “accidental catch”. But another part of the catch (which depends of the gear and the fishery, and that sometimes can represent a very large part of the total catch) has no commercial interest and is thrown overboard. This is what we call discards.

A fish may lack commercial interest because it is not edible, or it does not belong to a marketable species. Or it may be edible but has not reached the minimum landing size. It can also happen that it is edible and of legal size but is in such poor condition that it cannot be sold. And finally, specimens of commercial species and legal size can also be discarded to maximize the benefits, selecting the most valuable species and / or specimens. This can happen at the end of the fishing trips, when there is little space in the hold or when a species quota has nearly been caught. The motivations for discarding are diverse and a lot has been written about them.

Authors agree about the magnitude of the problem and the need to find solutions adapted to each fishery, because discards do not benefit anyone. In general, the measures to decrease discards are 1) technical, like increasing the selectivity of gear, 2) related to management, such as temporary closures of certain areas in which juveniles are very abundnat, or limiting the number of licenses, and 3) economical, such as fines, subsidies or quota replacement.

A FAO report in 19941 estimated that 27 million tonnes of fish were discarded annually. To give you an idea of ​​this figure, according to the 2015 report of CEPESCA (Spanish Confederation of Fisheries), Spain captured in 2013 right above 1 million tonnes of fish.

The Common Fisheries Policy of 2013 recently began to implement the so called landing obligation, which makes mandatory to land all catches of regulated commercial species (those for which there is a quota or minimum landing size). This regulation will be applied  to the entire European fleet and gradually to the different fisheries, regardless of whether they take place outside or within EU waters. Some exceptions will be considered for certain fisheries under several assumptions.

Although all catches of regulated commercial species will have to be landed, not everything will be directly marketed for human consumption, i.e. fish below the minimum landing size. It is thus necessary to find a good use for all the fish that will not be auctioned; and to optimize the use of this fraction of the catch it would be very convenient to know in advance what the boats carry in the hold.

The LIFE iSEAS project aims to solve this problem, demonstrating that European fishing can be sustainable by optimizing the use of the data we have and implementing innovative proposals for the management of discards. This project involves the Spanish Institute of Oceanography, the CSIC Institute of Marine Research, the Sea Technological Center (CETMAR), the Supercomputing Center of Galicia (CESGA), the University of Santiago de Compostela, JOSMAR SL, a company which manufactures fish processing machinery and OPROMAR, the Organization of Fish Producers of the Port and Ría de Marín.

You can find more information about the project at http://www.lifeiseas.eu/ Here I will just tell you that part of the project is a prototype that aims to do the work of a human observer without interfering with the work of the sailors. This prototype is the one I mentioned a few days ago. It will photograph our catch to identify and calculate the discarded biomass and the catch of target species.

The iObserver prototype installed above the conveyor belt

The iObserver ready for action

The project also contemplates other actions. One of them is the elaboration of models that will allow to estimate in the different fishing grounds the risk of catching unwanted species or size ranges, based on the information collected in surveys like ours, interviews with crew members, oceanographic surveys and the data generated daily by the fishing boats.

Other actions include the creation of a geoportal for the management of discard data, on-board and ground facilities for the recovery and management of discards, and of course a study of the socio-economic impact of the solutions proposed in the project.

1 Alverson et al. FAO Fisheries Technical Paper. No. 339. Rome, FAO. 1994. 233p.

The lab is ready too.

And don't you dare to think of kidnapping our cooks: we are ready too.