Abstract- Shellfish Aquaculture - Current Status and Future Opportunities

The harvest of shrimp, oysters and other shellfish has provided humans with healthy, nutritious and tasty seafood delicacies since the origins of mankind. Hatchery techniques have overcome dependence on wild stocks, enabling genetic improvement and rapid growth in shellfish aquaculture for an increasing variety of species. According to FAO statistics, in 2016, over 17.1 MMT of molluscs and over 7.8 MMT of crustaceans were produced in world aquaculture. From 2010, production grew 21.9% and 40.7% for molluscs and crustaceans respectively.

Mollusc culture is dominated by the bivalves: oysters, clams, scallops and mussels. Hatcheries hold, condition and spawn broodstock and then rear larvae and juveniles utilizing large quantities of microalgae as food. Growout techniques vary among species. One of the most important prerequisites is the selection of an appropriate site. In general, oysters are typically grown suspended in the water column or on structures elevated off the bottom in shallow water. Scallops are mainly grown in suspended culture and clams are typically grown in intertidal substrates.                                                                                                                      Crustacean culture is dominated by the farming of white shrimp Litopenaeus vannamei comprising almost 50% of world shrimp consumption. Hatchery methods are based on genetically selected broodstock and refined larval rearing methods. Disease has been a major factor in the development and growth of global white shrimp production. Disease control is achieved through pathogen exclusion, breeding for tolerance and management of culture systems. Commercial ongrowing systems today range from very large low density ponds, to more intensive aerated systems. As intensification increases, control of culture conditions improves. The most advanced systems today rely on biosecure super-intensive production.                                                                  

Farming of shellfish, has both positive and negative impacts on humans and on the environment. Farmed seafood provides more than half of the fisheries products consumed globally and over 80% of shellfish. With growing human populations and increasing disposable income, consumption is expected to grow considerably over the coming decades. The challenge will be how mankind meets the increasing global demand for healthy food while assuring environmental, social and economic sustainability. Shellfish culture typifies some of the greatest opportunities and most daunting problems. The culture of bivalve molluscs has minimal and mostly beneficial environmental impacts while sustainable culture of fed species such as shrimp can be much more challenging. Excellent ongoing research is elucidating pros and cons of shellfish farming in terms of water quality, coastal habitats, effects on wild conspecifics, sociopolitical conflicts, and socioeconomic opportunities in the context of sustainable healthful food production. This enables maximization of benefits while controlling conflicts and impacts. Advances in culture technologies, feeds and feeding, health management, application of information technologies and expanding integrated multitrophic systems offer a bright future for the growth of shellfish aquaculture for the benefit of mankind.