34 DECEMBER 2024 • WORLD AQUACULTURE • WWW.WAS.ORG FIGURE 1. Lakshadweep Islands off the Indian coast. Google Earth image, data from SIO, NOAA, US Navy, NGA and GEBCO. The growing demand for polychaetes currently relies on wild populations, but polychaetes collected from the wild are prone to infection, contaminants and pathogens. A study by Vijayan et al. (2005) demonstrated that they can carry White Spot Syndrome Virus (WSSV). Polychaetes can also act as carriers in the spread of emerging diseases such as Acute Hepatopancreatic Necrosis Disease (AHPND) caused by Vibrio parahaemolyticus and Hepatopancreatic Microsporidiosis (HPM) caused by Enterocytozoon hepatopenaei (EHP) (Thitamadee et al. 2016). Global Scenario of Polychaete Supplies Over 60 species of polychaetes are used for bait in recreational fisheries (Cole et al. 2018). The five marine species that have the highest retail prices per kilogram on the global market are Alitta virens, Arenicola defodiens, Diopatra aciculate, Glycera dibranchiata and Marphysa sanguinea. Globally, around 121,000 tonnes of polychaetes are collected annually, with a total estimated worth of £5.9 billion (Watson et al. 2017). Certain polychaetes can be cultured in controlled environments, using artificial seawater and appropriate substrates. They possess high fecundity and rapid larval development, which results in high rates of production. Commercial aquaculture of polychaetes was initiated in Northeast England with Nereis virens (sand worm) and during the same period the Netherlands also began culture activities. Initially, the production aimed to establish an alternative source for supplying existing bait markets (Olive 1999). In recent years certain marine polychaete species have been recognized as suitable candidates for Integrated Multitrophic Aquaculture (IMTA). Establishing affordable aquaculture methods for these worms will be crucial to maintain a balance between economic benefits and ecosystem conservation (Pombo et al. 2020). Indian Scenario In India, the polychaete trade is still in its early stages compared to other countries. Polychaete farming has not yet reached a fully commercial scale. As a result, India imports a significant portion The Lakshadweep islands in India are a cluster of coral islands. They are home to a variety of aquatic genetic resources, with potential for sustainable commercial utilization. Such resources, if cultivated, could provide muchneeded livelihood and income options and improve the lives of islanders who otherwise have very limited opportunities. In the past, we have demonstrated the cluster model by training women in raising ornamental shrimps and sea anemones for supplementing their family income (Ajith Kumar et. al. 2020). One of the important aspects to develop such interventions is that the Lakshadweep islands encompass a fragile ecosystem with very limited useable land. Therefore, all such interventions aimed at providing development opportunities for islanders should incorporate small footprints in terms of culture area, high-valued indigenous species, and minimal environmental impacts, and be based on circular economy principals. Here we address a new group of organisms, Polychaetes, which are known for their commercial potential in aquaculture and are present in these islands. The islands do not currently have any aquaculture activity; hence it could be possible to produce specific pathogen free (SPF) polychaetes for supplying industry needs. Nevertheless, appropriate testing and biosecurity would be practiced in such production facilities. Polychaetes are important organisms in the aquatic ecosystem, serving as food for fish, shrimp and other marine organisms. They are utilized as fishing baits due to their attraction for many target species. In the aquaculture sector, larvae and adult polychaetes are fed to many important fishes and crustaceans. Polychaetes are a major component of diets used in many shrimp hatcheries as well as in the ornamental fish sector, improving growth and maturation in shrimp broodstock and colour quality in ornamental fishes (Murugesan et al. 2011, Murugesan and Balasubramanian 2021). Shrimp fed with SPF polychaetes are reported to produce higher numbers of nauplii per female, and exhibit increased maturation rates, better recovery rates after spawning, and better quality of spermatophores and eggs (SPF Shrimp Feeds, 2023). Polychaetes from Lakshadweep Islands, India: Opportunities for Widening Live Feed Resources for Commercial Aquaculture U.P. Mohammed Naeem, T. T. Ajith Kumar and Kuldeep K. Lal
RkJQdWJsaXNoZXIy MjExNDY=