Fish Farmer Field School

‘Tambak’ is the common Indonesian name for a brackish water fi sh pond, classically supporting a polyculture of milkfi sh (Chanos chanos) and brackish water shrimp. There is historical evidence of 400 year old tambak in South Sulawesi, naturally constructed in the lower meanders of river estuaries. Not until 1964, in response to increasing demand from Japan for shrimp (a result of post-World War II affl uence) did large-scale expansion and intensifi cation of culture occur in tambak. In 1984/85, the Indonesian central government developed policies to ramp up expansion and intensifi cation, through the INTAM program, which targeted twelve provinces in Indonesia. Much of the increase in tambak coverage took place in mangrove forests, as both mangroves and tambak require tidal fl ooding and adequate drainage.

Tambak can be a massive feature in the coastal landscape, understood by anyone fl ying into a major deltaic city in Indonesia such as Jakarta, Surabaya, Lampung or Makassar. The 16,000+ hectare tambak complex owned by PT CP Prima Genjot (a subsidiary of the Thai conglomerate Charoen Pokphand) in Lampung is the largest contiguous aquaculture complex in the world, having displaced a mangrove system itself worth an estimated USD 436 – 574 million when one considers the value of mangrove goods and services (Sathirathai and Barbier, 2001).

As mangroves were replaced by tambak, a new set of social, economic and environmental problems arose. Services once provided by mangroves, such as fl ood control, salt water buffering, and natural primary productivity were lost. Mangrove detritus (leaf-fall, dead roots and twigs) provides a food source for numerous plankton, animals and bacteria, which drives the near-shore or coastal food chain. Especially notable was the reduction in benefi cial animal plankton, including copepods, which are an important food for shrimp and juvenile fish.