The role of small-holder seed supply in commercial mariculture in South-east Asia

Abstract

Countries in South-east Asia are significant producers of aquacultured products and production is increasing. Seedstock for mariculture are provided from both wild capture (‘capture-based aquaculture’) and hatchery rearing (‘full-cycle aquaculture’). Collection of Palinurid lobster pueruli and juveniles is currently the sole source of seedstock for aquaculture. Other mariculture commodities, such as milkfish (Chanos chanos) and groupers (Family Serranidae, Sub-family Epinephelinae) are supported by a combination of wild-caught and hatchery-reared seedstock. Mariculture in South-east Asia is typified by low levels of vertical integration, and a high proportion of ‘small-scale’ hatcheries. In Indonesia, small-scale hatcheries are clustered in two main areas: Buleleng Regency in northern Bali and Situbondo in East Java, with small-scale hatcheries comprising 95% and 88% of hatcheries in each area respectively. Fingerling production from these hatcheries is considerable, with 7.3 million grouper and 2.5 billion milkfish fingerlings exported from Bali in 2016. Although several studies have quantitatively evaluated the benefits of small-scale hatcheries to local communities, scant attention has been paid to their regional impact. As an example, much of the global production of around 1 million tonnes per annum of milkfish is supported by fingerling production by small-scale hatcheries in Bali. Despite this acknowledged success, disease remains an ongoing problem for small-scale hatcheries with operators of grouper hatcheries in Bali categorising mortality and financial losses as ‘medium’ to ‘high’. A survey of small-scale hatcheries showed that biosecurity is poor and fish health management approaches are based on previous experience. Factors impacting these approaches include purchaser focus on price at the expense of quality, and limited numbers of hatchery staff with any formal aquaculture training. The impact of disease outbreaks remains a weakness for small-scale hatcheries, and consequently a weakness for the mariculture industries dependent on these as a seedstock source.