60 September 2009 tificial dykes or old bunds constructed for common roads, railway track or elevated land. This confined area of more than 1 ha is used only in a few districts, such as Midnapore (East), Midnapore (West), 24 Parganas (North), Burdwan and Malda. Areas of less than 1 ha are found in 24 Parganas (North and South), Midnapore, Hooghly, North Dinajpur and South Dinajpur. The open type refers to the DWR area having continuous areass of low lands or saucer shaped depressions, gradually deepening to the core area, without being enclosed by a dyke or any other means. The open type of DWR area is usually connected to all adjacent and nearby water sources after their inundation. Two Major Crops in DWR Area, an Important Achievement DWR areas probably do not receive enough focus and attention. These areas are important for harboring endangered wild rice cultivars and indigenous fish species, which are the pivotal parts of the gene pool. Raghusal Rakta, Panikalas, Kakuriya, Paloi, Agniban, Najani, Bhasamanik, Kalomota, Sadamota, Meghi, Kumrogarh, Marichsal, Bakoi, Kalma, Dubonagra, Chchow, Jalokamini, Gochi, Motadhan, Patnai, Digha, Ghatak, Chengul, Bozal, Kalirai, Solki, Aman, Lakhhildigha, Mugursail, Deshi, Kalma, Baloon, Kansai, and Beto are indigenous rice cultivars in DWR areas. These rice varieties are sown during April-May and their tall seedlings are developed during July-August in most of the areas. This season is known as Kharif, which aligns with the breeding period of most of the freshwater fishes. Extensive surveys on traditional capture fisheries in the DWR ecosystem recorded a number of indigenous fish species: climbing perch (Anabas testudineus), air breathing catfish (Clarias batrachus, Heteropneustes fossilis), feather backs (Notopterus notopterus), freshwater shark (Wallago attu), murrels (Channa punctatus, C. marulius, C. striatus, C. gachua), eel (Mastacembalus pankalus), non air breathing catfish (Mystus spp.), mola (Amblyopharyngodon mola), nados (Nandus nandus) and puntius (Puntius sarana, P. sophore), to mention a few. All these species are highly preferred by local people for their nutritive value as well as special culinary preferences. The traditional capture fishery in DWR has shown a range of production of wild fish and freshwater shrimp from 40-125 kg/ha/season that could not match the scale of standard yield in terms of production, when the average yield about 70.1 kg/ha/season in DWR has been considered insignificant. This average production could have been enhanced to reach a profit if standard management practices, such as stocking density, species composition, standard size group and supplementary feeding, had been adopted. In this context, closed DWR is ideal, where appropriate aquaculture management can be practiced. Closed Type DWR Area, an Ideal Habitat for Fish Culture Owing to its morphometry and topographical advantage, closed DWR areas can be adopted with better management practices for fish culture than the open type. It has been reported that about seven percent of DWR farmers deliberately capture and rear wild fish in relation to ricefish farming. Generally, during the monsoon, DWR areas initially become flooded by rain, thus getting connected to perennial water bodies where additional exchange of running water takes place. This connectivity immediately allows wild fish to migrate inside DWR areas. When they enter the field, they become confined in this closed system of DWR, connectivity of which is then made semipermeable with a bamboo barrier which allows inside water to be exchanged with an adjacent water source. As this type of DWR has dykes, bunds or some kind of barrier to prevent the escape of fish from inside the field, it provides an ideal site for integrated rice-fish culture. The closed DWR habitat is probably a facilitator for fish, in respect to their growth and development, inasmuch as they have access to all esDike of deep-water rice-fish farming area being utilized for growing vegetables. Bamboo-made trap used for catching fish from rice field.
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