Heavy landings of bull sharks in Digha, West Bengal

Elasmobranchs (sharks, rays, skates and guitarfishes) form one of the important commercial fisheries of West Bengal. They are not targeted but usually occur as by-catch and due to demand for sharks in the national and international markets are remunerative. West Bengal contributes 10.51% to the total elasmobranch landing of India. The local demand for shark or rays is very little but fish trading and processing units which supply such products to distant places such as Kochi, Chennai, Visakhapatnam and even to the international market procure sharks from the fishermen

Overview of elasmobranch fisheries of West Bengal in 2018

Elasmobranch fishery of West Bengal comprises of sharks, rays, guitarfishes and skates. Due to demand in the national and international market, the fishery has gained importance though it is not a targeted resource. The catch data showed that the fishery is in a declining phase since 2016. The estimated landing of elasmobranchs (3799 tonnes) has shown a further decrease of 12.6% during 2018 in West Bengal compared to 2017. Sharks form the major portion (48%) of the elasmobranch fishery followed by rays (40%) and guitarfishes (12%) during 2108 in West Bengal. The fishery flourished more during the first (January-March) and last quarter (October- December)of the year. Maximum catch of sharks have been observed in October followed by February. The gear-wise landings of sharks showed that multiday trawlers contributed 81% of the shark landings followed by mechanized gill netters (17%) and the remaining 2% by inboard gill netters. Maximum catch of rays have been observed during June followed by January and October. The rays were mainly exploited by trawlers (76%) followed by hook and lines (15%) and gill netters (8%). Maximum catch of guitarfishes was observed during January followed by August and February. Guitarfishes are landed mostly by trawlers (91%) followed by gill nets (9%). The elasmobranch resources in West Bengal are very diverse in nature. However, there is a continuous decline in the landings which could be detrimental in future if the resources are not managed properly. Hence, it is recommended to follow good management practices to ensure long term sustainability of the resources

Deformities recorded in fishes

During regular field visits to Digha Mohana Fish landing centre (West Bengal, India) during August, 2018 to October, 2019 period, five abnormal fishes were collected and are recorded as given below. Deformed specimens of Brevitrygon walga and Pateobatis bleekeri (Rays), a deformed embryo of the shark Scoliodon laticaudus, guitarfish Glaucostegus granulatus and pomfret Pampus argenteus were recorded among the commercial landing. The rays were found to have rostral deformit

Impact of Cyclone Amphan on marine fisheries of West Bengal

West Bengal has three coastal districts, namely, North 24-Praganas, South 24-Praganas and East Medinipur with a coastline of 158 km. With 59 marine fish landing centres, 76,981 fishermen households comprising of 3.8 lakh fisherfolks who are mostly traditional fishermen (Marine Fisheries Census, 2010) West Bengal contributes about 6-8% of the total marine fish landings of India. The predominantly exploited resources are Bombay duck, anchovies, Hilsa, ribbon fishes, sciaenids, pomfrets, catfishes, flatfishes, penaeid and non-penaeid prawns. Cyclones and storm surges are frequently occurring natural calamities in the stat

CMFRI establishes a Pilot Farm in the outfall channel of the Coastal Gujarat Powers Ltd., Mundra, Kutch District, Gujarat

A customized sea cage for the running waters of the outfall channel was designed and fabricated by the scientists of the Regional Centre, Veraval. Two square cages of 5m size made of Galvanised Iron pipes of 1.5" size, with base collars and hand rails was fabricated at the site and mounted with the square shape culture nets of suitable size procured

New record of the giant freshwater whipray, Urogymnus polylepis from West Bengal waters, east coast of India

The giant freshwater whipray, Urogymnus polylepis belongs to the family Dasyatidae, the most species-rich family of the order Myliobatiformes comprising 19 genera and 89 species (Last et al., 2016a). Whiprays (subfamily Urogymninae) mostly live in marine environments worldwide in both tropical and temperate waters, while only a few species penetrate into estuarine and freshwater environments due to their remarkable physiological adaptability (Last et al., 2016b). Urogymnus polylepis is one of such species which primarily lives in freshwater environment; however there are records from brackish waters and even from marine coastal habitats (Last et al., 2010; Vidthayanon, et al. 2016)

Hazardous oil spill in Mumbai Port and adjacent fishing areas

A catastrophic collision of two merchant ships occurred in Mumbai Port on 7th August 2010 which resulted in spilling of about 800 t bunker oil and tumbling of 293 cargo containers with hazardous chemicals in the sea

Economic efficiency indicators of multi-day trawl fleet in Digha, northeast coast of India

Digha Mohana is a major fish landing and auction centre on the Northeast coast of India that supports livelihood and contributes to fisheries export. Trawl fishing is the major fishing operation observed in the region, where multi-day operations (MD) less than six days and > 6 days are in practice. In this study, we collected primary data on input and output factors in these two fleets to investigate the economic efficiency in fishing operations for 2018-2019

Fishery and stock assessment of the three-spot swimming crab Portunus sanguinolentus (Herbst, 1783) off Veraval, Gujarat

The fishery and stock characteristics of Portunus sanguinolentus was studied during 2009-2010 from Veraval waters. The average annual landing was 322 t, which constituted about 40% of the total edible crab landings at Veraval. Length-weight relationship showed isometric growth. L∞, K and t0 estimated were 178.7 mm, 1.2 yr-1 and -0.08 yr, respectively. Total mortality rate (Z), fishing mortality rate (F) and natural mortality rate (M) were estimated to be 4.69 yr-1, 2.85 yr-1 and 1.84 yr-1, respectively. The estimated length at capture (L50) and length at maturity (LM50) were 101.33 mm and 96.89 mm, respectively, indicating that the crabs enter into peak exploitation phase after attaining sexual maturity. The species is a continuous spawner and shows peak recruitment during May and August. The current exploitation rate (Ecur) was found to be 0.61 which is equal to E0.1 estimated by Beverton and Holt yield per recruit analysis. Thompson and Bell bio-economic analysis showed that species can be exploited at the present level to maintain the revenue from the fishery at economic level

ଓଡ଼ିଶାରେ ସାମୁଦ୍ରିକ ଶୈବାଳ ଚାଷର ସୁଯୋଗ, ସମସ୍ୟା ଏବଂ ଏହାର ସମାଧାନ (Seaweed farming in Odisha: Opportunities and Challenges -Odia version)

ଓଡ଼ିଶାରେ ସାମୁଦ୍ରିକ ଶୈବାଳ ଚାଷର ସୁଯୋଗ, ସମସ୍ୟା ଏବଂ ଏହାର ସମାଧାନ (Seaweed farming in Odisha: Opportunities and Challenges -Odia version