The Cíes Islands have become the setting for the first restocking of spider crabs carried out within the Maritime-Terrestrial National Park of the Atlantic Islands of Galicia. A total of 666 juvenile spider crabs and 750 juvenile shrimp were returned to the sea as part of a regenerative aquaculture project that seeks to strengthen the populations of these species and improve the biodiversity of Galician seabeds.
The spider crab specimens come from wild females collected in the Vigo estuary, in the area around Nerga and Punta Borneira, before they spawned. The females were transferred to the facilities of Octolarvae, in Moaña, where they completed the reproductive process under controlled conditions and without fishing pressure.
In the laboratory, the larvae were fed and cared for over several weeks until reaching the juvenile stage, a key moment in their development. The spider crab (Maja brachydactyla) goes through different larval stages before becoming a juvenile specimen ready to adapt to the natural environment. According to those responsible for the project, the small crustaceans remained under constant monitoring until they overcame their first moults, an especially delicate stage.
The release took place last 21 August in the Cíes, where 525 one-month-old specimens, 85 two-month-old specimens and 56 three-month-old specimens were returned to the sea. Once on the seabed, the researchers observed how the juveniles immediately began to cover their carapace with elements from their surroundings, a natural behaviour that allows them to camouflage themselves and increase their chances of survival.
The action is part of Acuiregal, a joint unit promoted by Octolarvae together with the Spanish National Research Council (CSIC) and the Institute of Marine Research (IIM). The objective is to rigorously assess the ecological and also socioeconomic impact of the restocking operations carried out, while developing new tools for monitoring marine species and ecosystem health.
The day was completed with the release of 750 juvenile shrimp between one and two months of age, obtained from females provided by the fishermen's guilds of Cangas and A Guarda. The collaboration of the fishermen's guilds, the National Parks Network and the Coast Guard Service is fundamental for rescuing eggs and larvae that might otherwise be lost.
In one year of activity, Octolarvae has already exceeded 600,000 specimens released into the natural environment, including larvae and juveniles of species such as octopus, squid, lobster, velvet crab, spider crab, cuttlefish and shrimp. A figure that places the Vigo estuary as a benchmark in research and regenerative aquaculture applied to the conservation of Galicia's marine ecosystems.
