Fisheries production in Southeast Asian farmer managed aquatic systems (FMAS): I. Characterisation of systems

Southeast Asian rice farmers often manage aquatic habitats and resources on their land to increase production of aquatic animals. We introduce the concept of ‘farmer-managed aquatic systems’ (FMAS) to capture the diversity of these resource systems at the interface of aquaculture and capture fisheries and characterize FMAS in contrasting agro-ecosystems of Cambodia, Thailand and Vietnam. Cambodian and Thai FMAS yielded primarily self-recruiting species (SRS) and were managed to allow or attract them, while Vietnamese FMAS were managed more intensively to produce mostly hatchery-reared species. More than 90% of rice farming households in the study areas of Cambodia and Thailand harvested aquatic animals from their land, and about 70% created aquatic habitats such as ponds in addition to rice fields in order to increase aquatic resource production. Cambodian households created and utilized a wide variety of man-made aquatic habitats, while Thai households created predominantly trap ponds. In contrast, less than half of Vietnamese farming households harvested SRS and very few undertook FMAS management specifically for them. Vietnamese FMAS were intensively stocked and managed as aquaculture systems, with SRS accounting for less than 30% of production. Nonetheless, SRS production per area of FMAS was comparable in the three countries. Contrasting FMAS characteristics in different study areas reflect underlying differences in agro-ecosystems, aquaculture technologies, farmer livelihoods and markets.