Impact of climate change on marine sector

Climate over the Earth is showing perceptible changes over both global and regional scales and the warming effects are now being felt across many parts of the world including India (Vivekanandan, 2010). Human activities are increasing the levels of carbon dioxide and other greenhouse gases in the atmosphere leading to a rise in atmospheric temperature. Since the year 1750, the level of atmospheric CO2 has risen from 280 ppm to 401 ppm in 2015, and if unchecked, will be at around 560 ppm by the year 2050

Effect of bottom trawling on physico-chemical parameters, benthos and fish fauna of Mangalore Coast, Karnataka State

Trawling, the most efficient method of catching fish world over is also found to be the most important human caused physical disturbance on the world's continental shelves and hence the physical destruction of ecosystems.Trawl gears often catch additional untargeted organisms, which are generally not commercially valuable and subsequently discarded dead or alive.Effect of trawling has been studied world-over in the last few years but relatively few studies have been conducted in the Indian waters.Habitat disturbance by otter trawling is probably one of the most significant threats to marine benthic biodiversity. A study has been carried out to assess the short and long term effects of bottom trawling on benthic com m unities in the inshore bottom habitat off Mangalore coast by which an area of the sea bottom is disturbed by fishing gear and the post-disturbance impact on the biota is compared and to assess the quantity of discards, incidentals and juvenile fishes which otherwise form the non-target groups in the commercial trawling

Perspective plan and strategy for development of marine capture fisheries in India

Indian marine fisheries which existed as sustenance fishery for years, underwent a series o f change with the advent o f mechanisation in the fifties evolving itself into a multi-billion dollar industry. The demand for fish in the next decade is expected to increase due to the awareness of the people on the nutritive value o f fish. Sustainability o f marine fish landings at the projected level is a major concern and there exists limited scope to increase the capture harvest in future as the production is stagnating between 2.5-3.0 m t since mid-90s

Trophic levels and methods for stomach content analysis of fishes

Trophic levels and methods for stomach content analysis of fishe

First record of Polka-dot ribbonfish Desmodema polystictum (Pisces: Trachipteridae) from Indian waters

Polka-dot ribbonfish Desmodema polystictum was recorded for the first time from Indian waters. A single specimen of D. polystictum (107 cm total length and weighing 480 g) was collected from Tharuvaikulam landing centre, north to Tuticorin, on the south-east coast of India during September 2010. The distinguishing characters of the species from other species of the family are discussed. Morphometric and meristic characters of D. polystictum are presented in this paper. With the present report, the distribution area of this species now extends to the Indian waters

Heavy landing of unicorn leatherjacket Aluterus monoceros by trawlers at Tuticorin Fishing Harbour of the Gulf of Mannar

The redtoothed triggerfish (Odonus niger) of the family Balistidae is a reef associated species landed by trawl nets operated along the Karnataka coast. This species forms dense aggregations in inshore waters and were not targeted till recently due to their poor market demand. The triggerfish shoals are intentionally avoided by the trawlers and the incidental catches are either discarded or brought ashore when there is available deck space for storage. Such small quantities landed are auctioned along with the miscellaneous fish groups. Some interest was evinced on this species by the fish meal traders due to limited availability of raw materials during the year 2008

Age and growth of three Indian major carps from Hirakud reservoir

Studies on the age and growth of three Indian major carps viz. Cotlo catlo (Ham). Cirrhino mrigolo (Ham) Dnd Lobeo rahita (Ham) based on scale and the length frequency data are presented. The markings on the sca les of these fishes were used as indices of age, aftar ascertaining the annual nature of formation of growth checks. It was found that in these three fishes rings were laid down almost during the same period i.e. May to August. The fesult obtained from scale study is compared with Petersen Method. A close agreement can be seen in their va lues obtained. Von Bertalanffy's growth equation was used for fitting the growth data obtained by scale study and it adequate ly describe the actual growth of those fishe s. The length at age and the rate of growth of these fishes were compared and it was found that rate of increase in length was faster during the initial periods of life and dec rease when they become old

Methods of stomach content analysis of fishes- Winter School on Towards Ecosystem Based Management of Marine Fisheries – Building Mass Balance Trophic and Simulation Models

The study of the feeding habits of fish and other animals based upon analysis of stomach content has become a standard practice (Hyslop 1980). Stomach content analysis provides important insight into fish feeding patterns and quantitative assessment of food habits is an important aspect of fisheries management. Lagler (1949) pointed out that the gut contents only indicate what the fish would feed on. Accurate description of fish diets and feeding habits also provides the basis for understanding trophic interactions in aquatic food webs. Diets of fishes represent an integration of many important ecological components that included behavior, condition, habitat use, energy intake and inter/intra specific interactions. A food habit study might be conducted to determine the most frequently consumed prey or to determine the relative importance of different food types to fish nutrition and to quantify the consumption rate of individual prey types. Each of these questions requires information on fish diets and necessitates different approaches in how one collects and analyzes data. Here, we outline qualitative and quantitative techniques used to describe food habits and feeding patterns of fishes

Field Identification of Threadfin breams, Silverbellies, Croakers and Bullseye

Nemipterids are one among the most commercially important groups of marine fishes in the tropical Indo-West Pacific region. Family Nemipteridae comprises of five genera: Nemipterus, Parascolopsis, Pentapodus, Scaevius, and Scolopsis. Nemipterus is popularly known as “pink perch”, contributed to 4.78% (1,62,764 t) of the total fish landings in the country during 2015

Unusual heavy landing of rays and skates at Tuticorin Fisheries Harbour

Tuticorin coast is known for the rich elasmobranch resources consisting of sharks, rays and skates. However, the landing of the resource was declining over the years. Elasmobranchs are mainly caught by trawlers, hooks and line and gillnets. At Tuticorin Fisheries Harbour (TFH), which is one of the major landing centre along the Gulf of Mannar (GOM) coast, the trawl fishery was excellent when fishing resumed on 30th May 2009 after the 45 day monsoon ban. On 15th of July 2009, unusual heavy landing of rays and skates was noticed (Fig. 1). The landing of rays and skates on this day alone was estimated as 33.3 t consisting of nine species of rays and four species of skate