Growth performances, feeding ecology and prey preferences of Mystus tengara (Hamilton, 1822) reared in low saline homestead traditional polyculture ponds in Sundarbans were studied for 12 months. Mixed carp early fingerlings (4.98±0.61 cm, 1.09±0.26 g) @ 14000 nos ha-1 and wild collected mixed bagrid catfish juveniles (5.09±0.48 cm, 1.38±0.11 g) including M. tengara were stocked @ 5000 juveniles ha-1. Farm yard manure @ 200 kg ha-1 was applied monthly and household dining wastes (11.37±2.08 kg ha-1 day-1) were thrown in the ponds almost daily following traditional practice. Fishes attained 31.56±2.08 g (13.92±0.88 cm) with specific growth rate of 0.95±0.15 % day-1 and exponent value of Length-Weight Relationship (b=2.99) indicated isometric growth. Numeric order of dominance of prey groups in water were Chlorophyceae, Myxophyceae, Bacillariophyceae, Insect parts and larvae, Copepods, Rotifers and Cladoceran, Fish parts and larvae, unidentified materials and Crustacean parts. Whereas, order of dominance of prey groups in stomach were Insect parts and larvae, Copepods, Myxophyceae, Rotifers and Cladoceran, Fish parts and larvae, Bacillariophyceae, Chlorophyceae, Crustacean parts and unidentified materials. Prey electivity analysis indicated significant active selection of Insect parts and larvae (E= +0.36±0.06) and Copepods (E= +0.30±0.12). Crustacean parts, Rotifers and Cladocera and Fish parts and larvae were also positively selected but were not significant. This study reveals that M. tengara is a carnivorous fish mostly preferring Insect larvae and Copepods. M. tengara can be added in low saline polyculture ponds to improve profitability and can be considered as a biological tool for Insect control.

The presence of two-faced toadfish Bifax lacinia was confirmed based on a single specimen, 244 mm standard length (SL), caught in the waters of Salalah port, Oman, the Arabian Sea in February 2016. Descriptions, illustrations, meristic and morphometric data are presented. The species is considered as an endemic of the southern Oman waters. Currently, the habitat of B. lacinia in Salalah port is under threat of the destruction due to the planned extension of the port.

The Kievka Bay is one of the cleanest regions on the Far East coast of Russia. There are no anthropogenic impacts on the coastal area, and thus the influence of pollutants on the state of fish health is minimized. Histopathological examination of black plaice was performed to study the background level of morbidity and the occurrence of pathological alterations in tissues of fi shes from this ecologically clean region. Different pathological alterations were detected in fi shes sampled. The most surprising was a disease of black plaice, where necrotic changes were found in the gonads of 28% of the males, and the destructive changes were absent in females. In the gills, pathogenic microorganisms were detected, which induced strong hyperplasia of the respiratory epithelium, fusion of lamellas, and necrosis of pillar cells, in 28% of the individuals. Diseases of the liver were recorded for two fishes that comprised 8% of the total number, in one case – granulomatous inflammation. Besides that some fishes had a diffuse necrosis in the liver. In the kidneys of all sampled fish, parasites were present in the lumen of the renal duct, very likely a moderately pathogenic species, as the consequences of parasitism were insignificant and for a smaller part of fishes – moderate. Thus, different pathological alterations were found in all investigated organs, and, in most cases, it was possible to establish their occurrence with parasitism.

This paper attempts to conduct a survey in the commonly edible finfish species collected from EKW during three seasons of 2016. Eastern Kolkata Wetland (EKW) is the only designated Ramsar Site in West Bengal The wetland with an area of about 12, 500 hectares act as natural kidneys and is also the natural sewage treatment plant for the ever increasing city of Kolkata. This multiple-use wetland lies on the eastern fringes of the city and includes a garbage dump known as Dhapa Square Mile, a mosaic of vegetable fields, a series of 300-odd fishponds connected by major and secondary canals, paddy fields, wholesale markets, a few roads, and 43 villages with an ever increasing population. The fishponds produce some 13,000 tons of fi sh annually, whose yield is at 2-4 times higher than average fish ponds, is among the best of any freshwater pisciculture in the country. Some 150 tons of vegetables per day are harvested from small-scale plots irrigated with waste water. It is essential to conduct a survey of the bioaccumulation pattern of toxic heavy metals such as Pb, Cd, Cr, and Hg in the finfish species commonly consumed by people in this region. The survey was carried out during three seasons of 2016. The accumulated toxic heavy metals were found in the order Pb > Cd > Cr > Hg. The seasonal order was Monsoon > Postmonsoon > Premonsoon. The seasonal variation might be the effect of monsoonal runoff from the highly urbanized and industrial city of Kolkata that convey huge quantum of effluents in the water of EKW. Such study has immense importance as fi shes are consumed by a large percentage of the people in and around Kolkata. This study would also provide a roadmap for researchers and policymakers to identify and implement effective and sustainable measures to counteract the increasing trends of pollution levels in natural ecosystems.