WWW.WAS.ORG • WORLD AQUACULTURE • SEPTEMBER 2016 13 (CONTINUED ON PAGE 15) mariculture industry of the region will have a better chance for survival, with long-term and sustainable growth. Seed Production The first attempts of spawning under controlled conditions in the region occurred about 20 years ago. Hatchery capacity has grown slowly and currently stands at about 20 million spat per year. This number is sufficient to meet the needs of all current scallop producers and government research centers. In addition to seed production, hatcheries are involved with social projects, including “how-to” workshops, specialized training, and environmental educational programs for producers. Larviculture methods are based on industry-standard, wellpracticed protocols, starting with obtaining fertilized eggs from broodstock scallops collected from the wild that are greater than 75 mm in shell length and older than 18 months. Gravid broodstock are first exposed to increased water temperature in the laboratory, i.e. from 20 to 24 C (Rupp et al. 2004, Sühnel et al. 2014). Because scallops are hermaphrodites, the process is closely monitored to avoid self-fertilization and decrease stock inbreeding. Spawned embryos are then transferred to larviculture tanks and fed initially with a mixture of cultured microalgal species, mostly Isochrysis galbana, Pavlova lutheri and Nannochloropsis oculata. After the fifth day, four additional species (Chaetoceros calcitrans, C. gracilis, C. muelleri, and Bellerochea polymorpha) are blended with the first three species to form the larval diet. After the larval rearing period, pediveligers are transferred to settlement tanks. Once settlement occurs, larvae are culled to specific densities, with continued feeding of the seven-species microalgal mixture. After 30 days, shell formation starts to occur and the tiny scallops are transferred to the sea in settling lantern nets for another 30 days to allow continued growth on natural feeds and for shell hardening, facilitated by the natural bicarbonate titers of the coastal seawater. Finally the mature seed scallops are transferred to nursery lantern nets, and after an additional 30-d nursery period (now approximately 90-95 days total in the nursery phase), the young scallops are ready to be stocked into lantern net systems for growout. Production Systems The most common production system is longlines affixed at regular intervals with lantern nets at 5-10 levels. Generally, longlines are 50 m long and lantern nets are attached with a minimum of 80 cm between each other to avoid tangling and to maintain good water circulation within the arrays. The distance between arrays can change according to ocean dynamics such as tidal regimes, wind fetch intensity and sea currents. The distance between longlines is usually set at about 5 m and is based on vessel traffic intensity to avoid damage to the longline arrays and for reduction of vesselinduced stress on the scallops below. There are basically two types of lantern net culture systems: surface arrays and submerged, water column arrays (Lodeiros et al. 1998, Mendonza et al. 2003). The surface culture system is mostly implemented by smaller producers, given their lower operating cost. In this system lantern nets are located at 3-5 m depth and a string of buoys for flotation is located at the water surface. In in a variety of environments suitable for diverse mariculture practices and approaches. In addition, the tropical climate, with an average surface water temperature of 23-25 C, is ideal for scallop production, allowing year-round production. Most scallop farming in Brazil is concentrated at Ilha Grande Bay, near the municipality of Angra dos Reis. This region has a rich marine biodiversity, ranging from benthic organisms to top trophic predators. Such biodiversity, combined with the unique coastal geomorphology, make this region very attractive to ecologists and nature lovers and for ecotourism and diving. This region is strategically located between two big economic centers, São Paulo to the south and Rio de Janeiro to the north, which are the main urban consumer markets for mariculture production from the region. The local communities in the region are mostly represented by artisanal fishermen families, whose family and cultural connections with the ocean extend back many generations. The beautiful and relatively un-spoiled coastal environments and social and cultural factors have combined to allow this region to become a major scallop mariculture producing area, with a focus on sustainable production. The sector has the support of and is integrated well with the local community and is also supported by guidance provided by local and Federal Brazilian government oversight. Scallop production fits well into the social and physiographic context of this region and presents an opportunity for development of a highly profitable mariculture sector. Many former fishermen have adopted scallop culture as their new full-time occupation. Interest from the local community to become scallop producers is increasing rapidly, given that the activity is deeply rooted in their culture and ancestral life practices, and presents a new and modern way to earn a healthful living from the sea. A bonus is the timeliness of integrating sustainable aquafarming practices into the new and developing industry. This trend will promote long-term ecosystem protection and regeneration, benefiting the biodiversity of the natural marine resources in this region. Because fresh scallops command high prices in the marketplace, scallop mariculture provides a greatly needed source of increased income for local fisherfolk, their families, and the community at large. In addition, as health awareness and the root causes of devastating diseases such as heart disease and arteriosclerosis become better understood by the general public in Brazil and by coastal populations in particular, there is an increasing demand for seafood, including scallops, to replace other forms of animal protein in diets and on menus. This is especially true for fresh, locallyproduced seafood products that, in addition to their noted health benefits, can command a price premium in the marketplace. Federal government incentives and the private sector and producer associations have been supporting scallop culture through research activities, seed production, social programs and facilitating regulatory pathways to further develop the activity. In addition, the local Department of Fisheries and Aquaculture has agreements in place with a large regional hatchery (IED-BIG) and has played a major role in monitoring and assisting local producers with farm siting advice, assistance with production methodology and husbandry techniques, monitoring and biometrics, harvesting techniques, and even commercialization and marketing. This government support and interaction has helped to ensure that the nascent scallop
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