Journal of Environment and Sociobiology

B. K. Mahapatra ¹

Affiliations
1 Central Institute of Fisheries Education, Deemed University (ICAR), Kolkata Centre, Sector-V, Salt Lake City, Kolkata-700 091, IN

Abstract

East Kolkata Wetlands (EKW), the only Ramsar site in West Bengal, is very significant for the wise use of sewage water, especially for aquaculture and harbouring the biological diversity. The commercially important aquatic species in the EKW includes 58 species of fish, 11 species of prawns, 3 species of crabs and 20 species of molluscs. Among the 58 species 10 are exotic and 48 are indigenous fish species. In EKW, among the 58 species of fish, 17 are culture species and 41 are wild species. In this unique system, 308 city-sewage-fed fisheries are operating where treatment of the sewage and pisciculture are performed in the same pond. Eight indigenous fish, viz., Catla catla, Cirrhinus mrigala, Labeo bata, Labeo calbasu, Labeo rohita, Lates calcarifer, Liza cephalous, Liza parsia and 9 exotic fish, i.e., Aristichthys nobillis nobilis, Clarias gariepinus, Ctenopharyngodon idela, Cyprinus carpio, Hypothalmicthyes molithrix, Oreochromis mossambica, Oreochromis nilotica, Pangassius sutchi, Piaractus brachypomus are being used for aquaculture. Fortyfive indigenous and 9 exotic fish species which are available naturally in EKW have good ornamental potential. Among the prawns commercially important species are: Macrobrachium lamarraei, Macrobrachium rude and Macrobrachium malcomonii. Sartoriana spinigera is an important crab species among all. Among the molluscan species important gastropods are: Bellamya bangalensis and Pila globosa, and Lamellidens marginalis is an important bivalve species in EKW.

This paper highlights the overview of fish biodiversity and utilization and discusses the management strategies to be implemented for the conservation of fish diversity in the EKW.

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S. Bhattacharya ¹, B. K. Mahapatra ¹

Affiliations
1 Central Institute of Fisheries Education, Deemed University (ICAR), Kolkata Centre, Sector-V, Salt Lake City, Kolkata-700 091, IN

Abstract

Snakeheads, commonly called Murrells, constitute one of the main stay of natural fisheries of India that fetch high price as food fish as well as aquarium fish. Even Murrells are also used in sport fishery and attracted the anglers. As food fish they occupy the top most rank for their flesh quality, less spines, taste, flavour, nutritive value and high protein as well as energy diet. As ornamental fish they are preferred by the hobbyist due to their hardy nature and bright colouration especially in their juvenile stage. Out of the 35 species recorded and reported globally, India represent 14 Channa species, i.e., Channa amphibeus (McClelland, 1845), Channa andrao Britz, 2013, Channa argus argus (Cantor, 1842), Channa argus warpachowskii (L. S. Berg, 1909), Channa aurantimaculatus (Musikasinthorn 2000), Channa barca (Hamilton 1822), Channa bleheri (Vierke 1822), Channa gachua (Hamilton 1822), Channa marulius (Hamilton 1822), Channa melanostigma Geetakumari&Vishwanath, 2011, Channa orientalis Bloch&J. G. Schneider, 1801, Channa punctata (Bloch 1793), Channa stewartii (Playfair 1867) and Channa striata (Bloch 1793) from wide variety of habitats, viz., swamps, lakes, sluggish rivers, mountain torrents and coldwater upland waters with the altitudes ranging from near sea level to above 5000 metres asl. Apart from this, one introduced species Channa diplogramma (F. Day, 1865) has been recorded from Kerala. These above mentioned 14 species are now believed to be under the threatened category. Indiscriminate killing through poisoning, overexploitation of brood and juveniles, destruction of breeding ground, pollution mainly caused by coal mines and ecological imbalances due to the introduction of exotic species might have resulted in the dwindling of Snakehead fishery alarmingly. More over Murrells are also susceptible to dreadful diseases. Epizootic Ulcerative Syndrome (EUS) particularly in colder climate of India causes a great loss in natural fishery.

However, Snakeheads, which are the most promising fishes of India, can be protected and conserved through concerted efforts from all the concerned stakeholders. Ban on the capture of juvenile ornamental fishes by seed collectors for aquarium trade should be enforced strictly. Captive breeding and farming and also ranching in major drainage would probably help in the enhancement of their stock. This would help in the development of sport fishery, ornamental fishery and also the overall fish production of the country.

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A. R. Sen ¹, B. K. Mahapatra ¹, Parimal Sardar ¹, S. Dutta ¹

Affiliations
1 ICAR-Central Institute of Fisheries Education (Deemed University), Kolkata Centre, 32 GN Block, Sector-V, Salt Lake, Kolkata - 700 91, IN

Abstract

Increasing knowledge regarding the impact of diet on human health along with state-of-the-art technologies has led to significant nutritional discoveries, product innovations and mass production on an unprecedented scale. The ocean is a largely unexplored treasure chest of pharmaceuticals, nutraceuticals and products for human health. Marine products continue to gain in worldwide popularity as they are being successfully utilized for in a wide range of human health benefits. The world's marine environment constitutes the greatest diversity of nutrients found on the planet. A number of plant and animal species are commonly used as food sources and are known to produce a vast array of chemical components that can be and are developed into nutraceutical ingredients with beneficial medicinal uses. The marine environment represents a relatively untapped source of functional ingredients that can be applied to various aspects of food processing, storage and fortification. Although large numbers of novel compounds have been isolated from marine organisms and many of these substances have pronounced biological activity, only very few have been marketed as pharmaceutical products. The exploration of the potential of marine biodiversity is still at a very early stage and requires the development of co-ordinated infrastructures as well as close collaboration between government, biotech industries and academia.

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Ambalika Ghosh ¹, B. K. Mahapatra ¹, A. K. Roy ¹

Affiliations
1 ICAR-Central Institute of Fisheries Education (Deemed University), Kolkata Centre, 32 GN Block, Sector-V, Salt Lake, Kolkata-700 91, IN

Abstract

West Bengal is rich in both Marine and Inland fisheries resources. Marine fisheries resources include coast line (158 km) and continental shelf (17000 sq km). Inland fishery resources comprise of inland water bodies (5.45 lakh ha), rivers and canals (2,526 km), reservoirs (0.17 lakh ha), tanks and ponds (2.76 lakh ha), flood plain lakes/derelict waters (0.42 lakh ha) and brackish water (2.10 lakh ha). An in-depth study on distribution of district-wise inland fishery resources reveals that South and North 24 Parganas, Murshidabad, Burdwan, Purba and Paschim Medinipur are dominant in impounded freshwater areas. The districts of Purulia, Bankura, and Birbhum constitute 41.07% and 33.57% of total reservoir and bund areas of 28049.85 ha. Damodar, Subarnarekha, Teesta, Atreyee and Mahananda are the major riverine resources.

From 6^th Five Year Plan to 11^th Five Year Plan there is an increase from 4.025 lakh ton to 14.72 lakh ton of fish production registering an increase of 3.66 times. From 2004-05 to 2011-12 inland and marine sectors registered an increase in fish production of 1.21 and 1.13 times respectively. Catch, marketing and distribution of fish production is undertaken through the 3066 fishing crafts,17348 mechanised boats, 59 fish landing centers and spread across 188 fishing villages involving 76,981 fishermen families comprising of 3,80,138 fisher-folk population. Attention is herein drawn to the policy planners for allocation of resources to the respective districts rich either in ponds and tanks or reservoirs/ bunds or riverine wetlands for sustainable enhanced production for rural employment generation. Trend of fish production in relation to cause-effect variables and potential for enhanced production and are also highlighted in this communication.

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