Stocking density of crabs and shrimp is low (1-3 m
-2
) compared to intensive farms (>30 m-2
), although
farmers expect mortalities and compensate by frequent pond restockings. They also do partial
harvests throughout the year resulting in an unknown shrimp density. However, the maximum
density is ultimately determined by the carrying capacity of the system which, with no additional
aeration (source of oxygen) and minimal supplementary feeding, remains low.
Pond management consists mostly of water exchange and the periodic cleaning of pond bottoms.
The timing and extent of these management strategies have a major impact on productivity and
account for much of the variation in production levels between farms within a single commune.
However, the economic viability of these extensive farms is largely dependent on farm size. Land
allocation in the mangrove protection zone in KG is typically less than 3 ha. Under the 7:3 policy,
where mangroves are grown adjacent to ponds, this results in less than 1 ha for production ponds