Coryphaena hippurus is a large pelagic species and constitutes an important by-catch in drift gillnet, trolling and long-line fishing gears operated along the Bay of Bengal, northeastern Indian Ocean. The present study, first from the region, is aimed at deciphering the feeding dynamics from 1150 individuals collected from 2017 to 2019. 32.17% of the fishes had empty stomachs or was with food traces, 45.57% had partially-full stomachs and 22.26% had full stomachs. The feeding intensity was inferred through stomach filling and predator-prey weight ratio, which was higher in May and lower in January, and increasing as increase in the fish size. Coryphaena hippurus is considered a piscivorous pelagic predator as pelagic teleosts contribute more than half of the prey species. Major prey species were big-eye scad (27.3%), squid (10.3%), crabs (9.3%), Indian mackerel (7.2%), Indian scad (5.9%), whitebaits (5.7%) and sardines (5.4%). Scads and crabs were abundantly preyed during summer and winter, while clupeids and engraulids in monsoon; however, no significant variations were observed in prey composition between sizes. Trophic Level was 4.22 ± 0.15 and Levins Standardized Niche Breadth Index was 0.30. Dietary niche breadth was higher during summer (0.48) and monsoon (0.33) and in fishes measuring 60.0–74.9 cm (0.51) and below 45.0 cm (0.48) indicating generalised feeding. This primary study from Bay of Bengal is the first comprehensive report on trophodynamics for the species and would contribute to its management using trophic interactions.

Perceptions of fishermen on climate change were studied from two coastal districts of Andhra Pradesh during 2011. Fishermen were interviewed to know their perception on climate change over the last 20 years, impact of change in climatic parameters on their lives as well as on marine fisheries and on the adaptation measures required. All fishermen contacted believed that climate had changed in the last two decades. Wind was ranked as the parameter that had changed the most in the last two decades. Sea status was ranked as the most problematic to fishermen. Avenue for safe exit from villages and coastal protection structures in case of natural calamities were the highest scoring adaptation measures. Wind was found the most critical parameter affecting marine fishery and overfishing was identified as the biggest problem facing fisheries.

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The reproductive biology of Nemipterus japonicus (Bloch, 1791) along the north-east coast of India was studied during 2012-2015 based on samples from the trawl landings at Digha, Paradeep, Visakhapatnam and Kakinada. Adults dominated the landings. Significant contribution by females was observed in most months of the year. Size at first maturity for females was 15.1 cm. Peak spawning season was during August to February and September to March in the northern and southern regions. Maturity and gonado-somatic index (GSI) were found to correlate well with sea surface temperature (SST). Fecundity increased with length and weight and varied from 13,176 to 1,30,798. Ova diameter distribution indicated the species to be a multiple/batch spawner.

The trophodynamics of Thunnus albacares (Bonnaterre, 1788) from the western Bay of Bengal was studied during 2012 – 2015. Feeding intensity revealed that 34.6 % of the fishes had empty-trace stomachs, 52.77% of the fishes had quarter full-half full stomachs and 12.44% of the fishes had three fourth full-gorged stomachs. Feeding intensity increased with an increase in body size of the fishes with high prey to predator weight ratios and with a third of the fishes above 160 cm fork length possessing three fourth full-gorged stomachs. Cephalopods (47%) dominated the prey constituents, followed by semi digested finfishes and shellfishes (28%), finfishes (16%) and crustaceans (9%). Significant shifts in prey items were observed with an increase in fish size. Though squids were predominant in the diet, however, with the increase in size, feeding shift has clearly been observed towards finfishes. Feeding preferences did not vary between sexes. Annual and seasonal similarities were recorded in their food and feeding habits. Prey-specific abundance indicated a relative specialized feeding pattern with high occurence of species belonging to the orders Teuthidae and Perciformes. Levins Standardized Niche Breadth Index of 0.16 indicated limited niche width in the feeding strategy of Thunnus albacares.