World Aquaculture 21 US$4.00 to US$6.50/Kg. Exports by 2002 to the US were 521 t (Seafood Watch 2004). Spotted Rose Snapper Aquaculture Feasibility Study Research in Costa Rica on spotted rose snapper began in the 1980s by INCOPESCA, and the Universidad Nacional (UNA). By 2002, a marine larval production laboratory was opened at the Parque Marino del Pacífico (PMP), a coastal management agency in the Ministry of Environment (MINAET). By 2003, PMP developed studies on the aquaculture sector that showed weak effectiveness of the public agencies, limited research and promotion, low enforcement, weak public policy and lack of interest from the private sector. An ecosystem-based-management (EBM) strategy was chosen and joint efforts were established among PMP, UNA, International Cooperation and Development Fund (ICDF) from Taiwan, INCOPESCA, MINAET and the Asociación de Pescadores de Isla Venado. The main objective was the establishment of local sustainable mariculture with artisanal fisheries focusing on spotted rose snapper. Broodstock and Spawning Wild spotted rose snappers (1-2 kg; 40-60 cm) to be used as broodstock were caught in the Gulf of Nicoya using long lines and maintained in 20 t fiberglass tanks. The fish were fed squid, shrimp and polichaetes (Americonouphis reesei). A second batch of broodstock was maintained as a backup. Hormonal induction of spawning was attempted but the results were not acceptable. By 2004, with spontaneous spawning as the goal, environmental manipulations were applied in the broodstock holding facility. Noise was avoided as much as possible by moving tanks to indoors, light intensity was decreased, a recirculating system was applied and the seawater pumping and treatment system was improved. By 2005 spontaneous spawning became frequent and the quantity of eggs increased. The larval rearing process was begun under controlled conditions. Three to four months was determined to be an adequate amount of time for adaptation of the broodstock. About 3,000,000 eggs were produced in 2005, 7,000,000 in 2006 and 15,000,000 in 2007 (Figure 3). December to February showed decreased production, probably because of low water temperature. Eggs were collected using a surface drainage system; buoyant eggs were skimmed and transferred to the larval rearing area. Total numbers of eggs were determined volumetrically. Fertilized eggs were placed in rearing tanks (500 L), with light aeration and a low rate of seawater exchange (400 percent per day). Larvae hatched about 17 hours after fertilization. Aeration was removed and water exchange stopped at the time of hatching. When the larvae ascended to the surface, they were collected and moved to 6 m3 larval tanks at density at about 33 larvae/L. Larval Rearing Larval rearing was difficult phase because of the small Fig. 3. Spontaneous spawning productions since June 2005 to June 2008. mouth (100 µm) of the spotted rose snapper. From 20052007 viable eggs were stocked in 6,000 L round fiberglass tanks, without any water exchange from day one to four. Hatched larvae were fed from day 2 post hatch with about 500 L per day of Tetraselmis chui (100-200 cells/mL) and renriched rotifers (5-20/mL) until day 20 post hatch. The rotifer, Brachionus plicatilis, was unsuccessful and was substituted with B. rotundiformis (about 10-20/mL). Rotifers were grown at 32 ppt salinity in a batch culture system and fed with Tetraselmys chui. Rotifers and algae in the rearing tanks were monitored daily and replenished as necessary. Enriched Artemia nauplii (1/mL) were added from day 15 to day 16 post hatch until day 30, and adult Artemia (2/ mL) from day 25 to day 35 post hatch. Daily water exchange was 30 percent, from day 5 to day 25. The weaning phase was about eight days, day 30-32, depending water temperature, The Artemia supply was decreased gradually until day 42. A diet of shrimp and fish was added. Daily water exchange was 100 percent from day 25 to day 40. Fingerlings were move to 6,000 L round fiberglass tanks from day 38-40 to day 55-60. Daily water exchange was 150 percent from day 40 to day 50. After the weaning phase, juveniles were maintained from three to 10 days before being move to a fish farm. The average rate of survival was two percent. Daily records were kept on water temperature (average 28.6ºC), salinity (average 33.8 ppt), pH (average 8.1) and dissolved oxygen (average 6.5 mg/L). By 2005, 10,000 juveniles were produced That was increased to 20,000 by 2006 and 70,000 by 2007 (Figure 4). The production was used at the pilot farm and by 2007, juveniles were also being released in the Gulf of Nicoya. Pilot Sea Farm Spotted rose snapper aquaculture areas along the Gulf of Nicoya were established based on biological, chemical and physical variables, waves, currents, wind protection, seafloor, beach distance, pollution, marine transport and information from INCOPESCA, UNA and Kapetsky et al. (1987). A community-based management approach was carried out for all the phases of the project including the pilot farm project. By 2005, a social survey and participatory processes were conducted in coastal communities of the Gulf of Nicoya. After six months a fisherman’s association from Venado Island was chosen. Financial and technical support
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