58 SEPTEMBER 2013 • WORLD AQUACULTURE • WWW.WAS.ORG of different life stages of tunas while working with relatively basic laboratory facilities. In 1992, IATTC scientists began collaborative work on the rearing of larval tunas with Japanese scientists in Japan. In 1993, this research led to a joint project centered at the Achotines Laboratory, initiated by the IATTC, the Overseas Fishery Cooperation Foundation (OFCF) of Japan, and the government of the Republic of Panama. The objective of the project was to investigate the culture and captive spawning of yellowfin tuna, snapper (Lutjanidae), and corvina (Sciaenidae) in land-based tanks to provide larvae and juveniles for research purposes. The infrastructure expansion necessary to hold yellowfin tuna broodstock and provide cultured food items for their larvae was completed by mid-1996, and construction of additional tanks and a concrete pier were completed by late 1999. Between 1993 and 2001, several Japanese scientists were based at the Achotines Laboratory, working with IATTC and ARAP scientists on spawning and rearing programs with yellowfin tuna, snapper and corvina. All project goals were achieved and this 8-year project was one of the most successful in the history of the OFCF. Research facilities of the Achotines Laboratory include six circular concrete tanks (one 1300 m3, two 170 m3 and three 85 m3) for broodfish, contained in a 1300-m2 covered, open-walled building. There is a dedicated area for incubating eggs and separate areas equipped for the rearing of larvae and juveniles in a variety of tank types and sizes, with the capacity to manipulate temperature, turbulence, light intensity, pH, and other parameters. A separate building contains a broodstock feed storage and preparation area, and algae (Fig. 3) and rotifer laboratory and production systems. Recently-expanded structures house a library and small conference room, an analytical laboratory, a nutritional analysis laboratory, and a DNA laboratory. There is also office space and housing for scientists, a workshop, and a pier in Achotines Bay for vessel operations. Vessels range from a 4.5-m inflatable to an offshorecapable 8.5-m vessel equipped with twin outboards, a GPS/Sounder and a custom-built live transport tank. Tuna Research Early studies of coastal tunas and mackerel. Through 1994, nearshore tropical tunas and scombrids, including early-juvenile black skipjack, bullet and/or frigate tunas (Auxis spp.) and sierra (Scomberomorus sierra), were collected at sea and reared at the Laboratory. This series of experiments resulted in published studies of nutrition, age and growth, physiology and development of vision in these species. Larval surveys conducted at sea in coastal waters near the Laboratory resulted in publications describing temporal and spatial patterns of distribution and at-sea starvation rates of tuna larvae in the Panama Bight. From 1992 to 1994, adult black skipjack captured in the wild spawned for extended periods in the Laboratory. Eggs and larvae hatched in captivity were used in several laboratory experiments to describe early development and growth of the species. By 1996, with expansion of Laboratory facilities, research emphasis at Achotines shifted to spawning and rearing of yellowfin tuna. Yellowfin tuna broodstock: capture, transport and growth. In early 1996, a yellowfin tuna broodstock population was first established in land-based tanks at the Achotines Laboratory. Over the past 17 years, yellowfin tuna have been captured in waters close to Achotines Bay, using rod and reel or hand lines and transported to the Laboratory in live tanks aboard skiffs. Prior to stocking in laboratory tanks, fish are measured, weighed, tagged with a microchip implant tag in the dorsal musculature, and injected with oxytetracycline (OTC). The tag allows each fish to be identified FIGURE 3. Algae (Nannochloropsis sp.) culture tanks (Photo: IATTC). FIGURE 4. Yellowfin grow to reproductive size and spawn in the main broodstock tank (Photo: www.boyceimage.com). FIGURE 5. Growth rates of wild and captive yellowfin tuna.
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