• Name of species:
    Milkfish (Chanos chanos).
  • Primary potential:
    Extensive aquaculture for human consumption. Use of juveniles as tuna bait.
  • Attributes for aquaculture/stock enhancement :

    . Milkfish is a warm water species and prefers water temperatures between 20-33°C

    . Unlike many other large saltwater fish it is herbivorous and feeds on cyanophyta (lingbya), diatoms and other similar food items- Broodstock can be raised and spawned in captivity to produce larvae in the hatchery

    . Spawns only in fully saline water. Females spawn up to 7 million epipelagic eggs (1.1-1.2 mm diameter) which hatch in about 24 hr. Spawning and fertilisation take place at night

    . The frequency of spawning per year is unknown

    . Eggs and larvae are pelagic up to 2-3 weeks

    . Larvae eat zooplankton; juveniles and adults eat cyanobacteria, soft algae, small benthic invertebrates, and even pelagic fish eggs and larvae

    . In nature, the larvae seek out clear coastal and estuarine waters warmer than 23°C with 10-32 ppt salinity and abundant phytoplankton. Incubating eggs and newly hatched larvae are transported to the shore by currents where they are gathered by people in brackish waters such as shallow sandy areas, mouths of rivers, and lagoons

    . Older larvae migrate onshore and settle in coastal wetlands (mangroves, estuaries) during the juvenile stage, or occasionally enter freshwater lakes

    . Under natural conditions, larvae and fry migrate inland seeking tidal pools and settle in them for 1 month until they become juveniles, then migrate into lagoons, lakes and shallow waters until they reach adolescence (24-45 cm fork length) before returning to the sea for further grown and sexual maturation

    . Milkfish attains sexual maturity in 5 years, both in the wild and under culture conditions

  • Culture methods :

    . Culture of this species is well developed in Asian countries, especially the Philippines, Indonesia and Thailand. Recently its culture was introduced into the Pacific region when culture was attempted in Kiribati. Currently Hawaii, Kiribati and Fiji are the only Pacific countries culturing milkfish

    . Larvae are collected from rivers and are grown in culture ponds into juveniles

    - Since milkfish is herbivorous, culture is by the extensive method where large bodies of pond waters over 1 to 5 hectares are fertilised with organic and/or inorganic fertilisers to enhance primary production. Fry are caught from the shallow tidal pools and lagoons and stocked in pre-fertilised culture ponds often at densities of 30-50 fry per square metre. Densities are reduced as the fish grow. Supplemental feeding with rice bran and other feedstuff is often done

  • Current production status :

    . Milkfish production in Fiji for 1996-1998 was worth approximately AUSD30,000 per year, with total pond area of about 80 ha

    . Hatchery-reared juveniles in Kiribati are exported to Fiji

    . Few other Pacific island countries are culturing milkfish, and production levels are uncertain

  • Marketing :

    . Most milkfish is produced for human consumption and marketed fresh, smoked, canned and frozen

    . A new market for the tuna bait industry is gaining popularity because cultured juvenile milkfish have been found to be excellent bait-fish for the tuna long line industry. This market is the driving force behind the introduction and development of the milkfish industry in Fiji. The price per kilogram for table fish and baitfish is unavailable at the time of writing

  • Comparative advantages/disadvantages (risks) of producing the species in the Pacific:


    Milkfish is low in the food chain (a herbivore/detritivore), and so food production is relatively simple.