There is a ten-year history of collaboration between the Agris Agency (Regional Agency for Agricultural Research) and more specifically between the Agris Fish Products Research Service and the Tortolì Fishermen Cooperative. This cooperation came about in between 2011 and 2012 because of the constant impulses of then Cooperative President Fabrizio Selenu(1971-2015). He came with the idea for an experimental hatchery of bivalve mollusks, the first of their kind to actually thrive in Sardinia. The aim was to pass, to the operators in the sector, the proper reproduction techniques of the species typical to the island’s lagoon environment. The original species being the true Mediterranean Ruditapes Decussatus, that have been heavily affected in recent years. In many natural environments they have been supplanted and replaced by their more resistant and better performing cousin, the Philippine clam Ruditapes Philippinarum
The Hatchery consists of:
– A department for the maintenance and conditioning of clam breeders where their sexual maturation is induced and accelerated in about 2 months. The native wild clams (collected in the lagoon) are kept within the department for about 1 year and they make up a big part of the breeding park.
– An emission plant, which allows the mature reproducers to release the gametes (male and female) which, after being taken, are used for the controlled fertilization phase (in the laboratory
– An incubation department for fertilized eggs and larval breeding, where the larvae are kept for about 2 weeks and a post-larval breeding department made up of rectangular tanks in which the juvenile stages of clams are kept for about 3 months.
In the various departments, the feeding of bivalve mollusks is ensured by phytoplankton produced in large volumes and distributed in the various sectors through metering pumps.
The selected and sterile algal strains, used to inoculate large volumes, come weekly from the AGRIS laboratories at the Agris company in Bonassai, located at km 18.6 of the Sassari Fertilia State Road.
From the hatchery the clams are pre-greased on FLUPSY (Floating Up-weller System) and at the size of about 10-12 mm they are ready for sowing in the lagoon, where after about 18 months they will reach commercial size.
The productive potential of the hatchery is about 1,000,000 individuals per year and these techniques are being transferred to operators in other Sardinian lagoons, in parallel with the repopulation of the Ruditapes Decussatus species.
In the experimental hatchery of Agris in the Tortolì lagoon in 2012, the first Mediterranean clams in Sardinia were obtained through controlled reproduction.
Another very important activity carried out by Agris at the Tortolì lagoon concerns the transfer of technology to the fishermen of the lagoon of the concave oyster farming (Crassostrea gigas) in polyethylene pockets measuring 90 x 50 cm kept floating through floating panels.
With this system in place it is possible, through the overturning of the special pockets, to keep the oysters dry for a certain number of hours. This in order to be able to clean them and to still have a high quality product whilst, at the same time, cutting the amount of work that is involved for the operators (less effort in the management of oysters).
The oyster is the most farmed bivalve mollusk with an annual production of about 4 million tons. Worldwide, China is the largest producer with a production of about 2.3 million tons p/year, while in Europe France is the largest producer (they produce about 150,000 tons).
In Italy, oyster farming dates back to Roman times. Pliny the Elder in the 1st century AD described the farming techniques used for the native species Ostrea Edulis, while the concave oyster was introduced only in the early twentieth century. Currently we can consider the Italian oyster farming as a rapidly developing activity and in this context Sardinia can aspire to a leading role in the national market thanks to its 1852 km of coastline and approximately 15,000 ha. of brackish waters and lagoons. It is characterized by an abundant primary production of phytoplankton, which gives it an enormous productive potential in regards of aquaculture production.
Another important activity carried out by Agris in the Tortolì lagoon concerns the controlled reproduction of the mullet used in the production of the delicious and precious Bottarga (Mugil Cephalus).
In Sardinia, Bottarga is mainly produced starting from mullet ovaries (Mugil cephalus species) and represents a traditional production of great economic value in the agri-food sector.
The decrease of M. Cephalus in the lagoons of Sardinia and the consequent decrease in the production of Bottarga, have pushed research to carry out scientific studies and experiments on the how and what of the reproduction of this species in a controlled environment in order to carry out a repopulation activity for production purposes. In the Sardinian ponds and in the Tortolì lagoon in particular.
All the experimental activities that are taking place at the Tortolì lagoon are certainly the result of a great commitment of Agris researchers and technicians, but all this could never have happened without the foresight and passion of the friend and genius Fabrizio Selenu, who still guides us today and for always from Heaven and encourages us to collaborate with his Cooperative.