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A fishery management pilot project for recovering hake population

European hake populations in the western Mediterranean Sea are overexploited. This is the conclusion of all the assessments made since 1992 until now by CSIC scientists at the Institut de Ciencias del Mar and from other research institutions, like IEO and IFREMER. Fishermen and administrations have joined to tackle fishery pressure.

Each sampling day, four trawls of one hour each are conducted. Image: ICM/CSICIn February 2014, Roses fishermen’s associations proposed a closed fishing area in the Roses’s Bay continental shelf, at depths between 120 to 130 meters. With the measure, and independently of the fishing method used, all hake catches have been stopped with the main objective of protecting the young hakes (Merluccius merluccius). The Catalan Government, using the European Fishery Funds (EFF) offered the opportunity of a co-management pilot plant involving the fishermen and the scientists of the CSIC’s Marine Science Institute (Institut de Ciències del Mar). The scientists are in charge of sampling and assessing the effects of the closure on hake populations. This project, which officially started the 1rst of March, is funded by the European fisheries fund (EFF).

All the involved partners agreed that the pilot fishery management measures need at least one year-period of duration, in order to have enough time to see the effects on the biomass, biodiversity and fish size distribution. Besides, they want to find out if the closure also benefits  non-target species that inhabit the same habitat, as well as the habitat restoration.

On board, the scientists annotate the quantity, weight and size of all the commercial species caught. Image: ICM/CSIC

Sampling every month

Laura Recasens, scientist at the Departament of Renovable Marine Resorces at the l’ICM-CSIC, and coordinator of the pilot project, explains: “we are conducting a monthly sampling onboard a comercial fishery vessel of the Roses harbour. Each sampling day, four trawls of one hour each are conducted (two in the closed area and the two other in a near area at the same depth).  Detailed information of each trawl is collected: the duration, position, depth and trawling speed, as well as the longitude of the fishing cable and the distance between the trawl doors”.

On board, the scientists annotate the quantity, weight and size of all the commercial species caught. Then, hake individuals are brought to the ICM’s laboratories, where they are sorted into the different commercial size categories. Sizes, weight, sex ratios, maturity stage and other biological characteristics are annotated. Discarded catches, mostly composed by benthonic organism, are also analyzed in order to classify the species, count and weight all the individuals.

Ulla Fernandez de Arcaya, a biologist at the ICM and coordinator of the project, says: “The positive effects of non-fishing area are especially noticeable in this benthic community. Several species, such as sponges, starfish, sea urchins and other organism that live on the seafloor have increased more in the non-fishing area than outside”.

Hake individuals and benthonic organisms are brought to the ICM’s laboratories, for further analysis. Image: ICM/CSIC

Joining expertises

Joan B. Company, researcher at the same department of the ICM and coordinator of another fishery management plan, says: “the experience of our centre in co-management process dates back to 2009, when we started discussions with fishermen and Catalan and Spanish governments about the management measures for the red shrimp of Palamós. Later, in 2012, scientists of our centre launched a new co-management project for the “sonso” (a small endemic fish from the Mediterranean Sea). As in these previous fishery management study cases, we also work together with fishermen in Roses. Fishermen offer us their experience”.

In the case of the European hake, says Joan B. Company, “according to the preliminary results of the first six months of closure, the effects are positive and the hake population has increased. We still have to wait for the final results to conclude if the management measures reach the objective of reducing juvenile catches, but we are optimistic as we have seen a promising recovery  tendency up to date”.

With these three management plans (red shrimp, ‘sonso’ and hake), the Institut de Ciencies del Mar has become European leader in undertaking fishery co-management measures and in co-participating with the social agents. This co-management  structure (scientists, fishermen, environmental groups and policy makers) will be promoted in other  Mediterranean countries because their successful results in fishery management.

Related links:

Instituto de Ciencias del Mar

Video del plan de la gamba de Palamós:

Els misteris del sonso: