Cultural Sustainability. Natural and Sustainable Production
The shellfish growing farms are well-delimited plots of land, but with different dimensions, on the seabed in the intertidal zone. For more than 500 years, the region’s inhabitants and surroundings have been exploiting the land, passing on their acquired knowledge throughout this period.
For the last 50 years, administrative concessions have been in charge of these farming fields’ exploitation. Its production occurs in the protected setting of Cortegada Island and along the Ulla-Deza River’s natural network. This natural habitat favors an ecosystem extremely rich in nutrients that feed the entire production of bivalves; a phenomenon that only takes place in the Arousa Estuary.
Fundamentally, the growers perform the shellfish culture tasks employing artisanal means; nevertheless, they progressively introduce new materials and techniques, aiming to improve and facilitate their working conditions, but consistently respecting the traditional methods. Likewise, new technology introduction has always helped them improve and increase production, promote marketing, and ensure traceability within their continuous commitment to quality.
On the larger culture fields, the farms are better structured; and as a result, seeding clam rhythms are established and combined with harvesting to obtain a higher yield per m2 a year. Therefore, growers plan and structure the seeding areas taking into account the natural set-on locations to foresee the seed growth projections, influenced by species and densities.
The production capacity of a mollusk culture field is affected by many factors, such as densities, natural settings in the designated and surrounding areas, the size of the seeds, storm-exposed places, sea currents, etc. To avoid seed shortages when the parks are highly crowded, growers perform intensive seeding areas, which can serve as a pre-fattening seedbed to foresee quality seeds for the subsequent extractions. High-quality seeds are of early age and have lengths between 15 and 20 millimeters.
Generally, the mollusk species in the growing culture farms are Pullet carpet shell clam (Venerupis pullastra), Grooved carpet shell clam (Ruditapes decussatus), and Japanese littleneck clam (Venerupis philippinarum), as well as the common Cockle (Cerastoderma edule). For shellfish harvesting, growers used traditional tools; for instance, different types of rakes called ganchas, raños, and rastillos, depending on the levels of water covering the plots.
Monitoring and Conservation
Natural predators also play a decisive role in the survival of juvenile specimens and, ultimately, production. Therefore, to catch them during their most vulnerable times, Carril growers use fishing gear and traditional Galician traps, called nasas, conforming to Decree 15/2011 issued on January 28, which regulates the gear, tackle, tools, equipment, and techniques permitted for the professional extraction of living marine resources in waters under the jurisdiction of the Autonomous Community of Galicia.
Occasionally, sand displacements might occur in the Carril growing farms, depending on the intensity of the waves, storms, and other atmospheric conditions. Therefore, it creates the need to replace or recondition them since the culture fields are artificial, requiring constant maintenance to keep their worth. Likewise, growers perform this activity usually between October and March for biological reasons, overseen and managed by the Department of the Sea.
Quality and Size Standards
The Carril shellfish growers develop sustainable aquaculture practices. This Association of Fish Producers is responsible for verifying that all of its affiliates comply with the Galician Autonomous Community’s Order dated July 27, 2012. This agency oversees and guarantees the minimum sizes for harvesting and selling various fishery products. By prohibiting the marketing of any product below the minimum standards specified for sale, this legislation pursues the objectives of guaranteeing the protection of marine organism juveniles and preserving the continuity of the resource. Regarding quality and presentation, they classify the product according to species and size, as stipulated in the regulations.
In addition to other details utilized for statistical purposes, the associates provide the organization with all the data and information necessary to confirm compliance with the legislation on the aquaculture exploitation, production, and marketing of their products. The Association also ensures conformity with legal quality and standards through the collective acquisition of seeds for its members and the corresponding verification of the required quality. They promote their sales through the Carril fish market and commercialization by releasing a guide for the product’s transfer to the facilities of their buyers.
In this framework, the organization performs mollusk culture farming in a sustainable and fundamentally artisanal manner, respecting the environment and using the natural ecosystem as their seeding fields (sementeras) which provide a large part of juvenile specimens and their diet.
Since its foundation, the Carril Association of Fish Producers has been actively promoting environmental awareness and pollution prevention, as it seriously harms the biology of clams and cockles in the culture farms, jeopardizing their production. As a result, they have carried out initiatives to manage and collect environmental data; for instance, their participation in a study by the University of Vigo to establish the effects of light pollution in the marine environment, which can change the predators’ activity, alter seasonal reproductive cycles, and modify the feeding behavior, impacting on the regeneration of mollusk culture farms.