Coastal Aquaculture and Mariculture (2+1)

Unit 5 - Finfish culture systems

5.1.2. Fry collection

• Milkfish don not mature and spawn naturally in captivity. They seem to spawn near the coast and larvae occur periodically along the sandy coasts and in the estuaries.
• Hence, most of the fry used for milk fish culture are collected from the wild.
• A variety of gears are used to collect milk fish fry from shallow coastal water. The most common collecting equipment comprises different types of dip nets, such as the triangular scissor net in the Philippines and the scoop net in Taiwan. Dip nets are particularly suited for areas with large concentrations of fry. Seine nets, drag nets and traps are also use by some fishermen.
• In traditional methods of fry capture in Indonesia special fry congregating devices are used, such as rock walls or lure line made of fibre ropes strung with plaited strips of coconut and banana leaves.
• Power boats are also use to tow seine nets and scoop nets. This extends the area of collection to off the immediate coast and is more efficient. The best collections are made at the creek mouths.
• The fry collectors sell fry to fry buyers who accumulate the fry in 2-6m³ shaded concrete tanks near the collection site in about 10 cm of water at a density of about 40,000 fry per tank.
• Fry are then packed in polythene bag filled with water and pure oxygen and deliver to fry dealers. Dealers hold the fry in cement tanks before selling to the farmers.