The Southeast Asian Fisheries Development Center (SEAFDEC) has found that fishponds and prawn farms have caused the decline of annual fish harvests. In a study, the Japanese-funded center said that small fishermen lose about 420,000 tons of fish every year due to the conversion of mangrove swamps to fishponds and prawns farms.

Fishponds, prawn farms reduce catch of Iloilo. (1991, August 1). Philippine Daily Inquirer, p. 6.