Hatchery based seed production with mainly wild-caught broodstock.
This system requires feed input. The fish-in-fish-out ratio is low, meaning that low volumes of fish feed are needed to produce one kilogram of giant tiger prawn. Feed traceability policies are strong and verifiable with most sources of feed ingredients certified as being environmentally responsible by reliable standards. There is transgenic genetically-modified plant material in some feed components.
Frequent water exchanges mean that effluent is discharged into the open water with this production method. Continuous negative impacts are caused to sensitive habitats, due to expanding shrimp farming over efforts to restore mangrove habitats. The escape risk is high, with escapes occurring during water exchanges, harvests and flooding events. Since the species is native to Vietnam, the environmental impacts are low. Diseases is a problem in shrimp farming, and to control disease outbreaks, farmers will use limited amounts of chemicals.
Vietnam has extensive environmental legislation, but in general, strict enforcement is lacking. Overall management is marginally effective.
