Existing shrimp farming systems and technology

In the south-western coastal areas (i.e. greater Khulan region) the cropping pattern is for brackish-water shrimp culture in dry months (December-July), followed by transplanted aman rice during July through to December. In some areas, shrimp farming is characterized by monoculture.

In the south-esastern coastal areas (i.e. Cox’s Bazaar region) shrimp are grown from May to November and for the rest of the year, the land is used for salt production.

In some parts of the south-eastern tidal area, rice alternates with shrimp and fish production (ESCAP 1988). The shrimp farmers mostly rely on wild  shrimp stock because there are only nine hatcheries in Bangladesh, all with  limited capacity for shrimp fry production. Furthermore, only one of these hatcheries, located in the south-astern zone, produces bagda (p. monodon) fry…. The preferered shrimp species (Karim 1995). The existing shrimp seed production capacity of commercial hatcheries is nowhere near the total requirement for Bangladesh’s increasing shrimp culture industry (Hussain 1994; Karim 1995). Consequently, shrimp farmers are forced to rely on wild stocks or the importation of fry, which lead to an increased cost of shrimp farming (Kashem 1996).

An improved extensive method is a slight modification of the traditional extensive method, whereby farmers apply a few components of shrimp farming technologies. This method is, perhaps, specific to shrimp aquaculture in Bangladesh and Vietnam. An annual yield of 250-1,000 kg of shrimp can be obtained (Mazid 1994; Ahmed 1996).

The semi-intensive method requires the incorporation of a nursery phase in the shrimp farming process. Shrimp fry obtained either from wild catch or com-mercial hatcheries are stocked in the nursery ponds at high density before transferring  to shrimp fields (ghers). The annual yield is 500-5,000 kg/ha (head on) with an average of 2,000 kg/ha (Rosenberry 1995). In 1995, only 1% of the shrimp farms in the country used this method (Begum and Banik 1995; Rosenberry 1995).

Intesive farming is practiced in small shrimp ponds with high stocking densities. This farming method entails heavy feeding, removal of farm waste, water exchange and installation of an aeration system. This method of production is vary uncommon in Bangladesh.