Tuna live-bait fishes - their exploitation, conservation and management in Lakshadweep

The total annual catch of baitfishes form pole and line fishing areas of Lakshadweep is estimated to be 1251. At Minicoy, the average annual catch is estimated at 9.11 and at Agatti it is estimated to be 51 t. Data from other baitfish fishing areas such as Suheli, Valiapani and Cheriyapani are virtually non-existent. Management options suggested earlier include the collection of fishery data from more areas, studying the biology and understanding the stock of exploited species, culture of suitable species and maintaining the health of the coral reefs of the islands. Future thrust areas for research to elucidate the factors that determine the baitfish fishery include a full review of the existing fishery and development of a baitfish statistics collection system

Tuna drift gillnet fishery at Chennai, Tamil Nadu- an update

The present study describes the status of multiday drift gillnet fishery for tuna from Chennai fishing harbour based on data for the years 2016 – 2017. The data is also compared with that during 1999- 2006. Both the craft and gear increased in size with consequent extension of fishing grounds and increase in the number of days/ fishing trip. The size of the boats increased to 20-23 m OAL from 11-12 m OAL and weight of the gear from 1 to more than 6 t. Annual average catch increased to 8523 t during 2016-2017 from 595 t during 1999-2006. Average catch per unit effort was 8310 kg as against 730 kg during 1999-2006. Yellowfin tuna, Thunnus albacares and Skipjack tuna, Katsuwonus pelamis were the dominant species. The stock position of skipjack tuna and yellowfin tuna vis-àvis the three indicators indicated that the percentage of mature yellowfin tuna in the catch in 2017 was 68%, fish in optimum length 35% and mega-spawners 33% whereas in skipjack tuna the respective percentages were 99.5, 21.1 and 79.1. Problems and prospects of multiday tuna drift gillnet fishery are also discussed

Problems and prospects of marine fisheries at Lakshadweep

The Lakshadweep sea is estimated to have an annual fishery potential of about 90,000 tonnes while the present yield is only about 6000 tonnes. ' Endowed with vast lagoons and tuna-rich oceanic waters, I fishing is an important component of the economy of Lakshadweep. Tunas form 87% of the fishery and is caught mainly by the pole-and-line technique-:-This method involves locating the tuna shoals, then attracting by chumming with live bait and water spraying, and finally, catching the fish using poles and lines with barbless hooks

Distribution and abundance of carangids along the EEZ India

Distribution and abundance of carangid groups of fish along the EEZ of India based on the data collected during 80 cruises undertaken by FORV Sagar Sampada is presented here. East coast of India showed maximum concentration of ctrangids with a catch rate of 64 kg/hr along the northeast coast. The least distribution was noticed along the northwest coast ( 5 kg/hr). Carangids formed up to a maximum of 19 % of the total bottom trawl catch along the northwest coast. With more than 20 species of carangids reported to be caught in various cruises, Decapterus spp formed the most dominant group, followed by species like Atule mate, Selar crumenophthalmus, Carangoides malabaricus etc. Depthwise distribution showed higher density in the 60-80 m range all along the coast excepting the Andaman-Nicobar archipelago. Areawise, higher densities of carangids were noticed at latitude-longitude 7°N - 77°E, 1TN - 75°E, 1TN - 79°E, 14°N - 80°E , 18°N - 72°E, 19°N -85°E and 19°N -86°E. Seasonally, carangids were represented in the catch more during the monsoon especially along the northeast and southwest coasts. Potential yield of carangids along the EEZ of India is estimated to be 94971 tonne

Fishery, biology and stock assessment of small tunas

Fishery Survey of India has brought out publications on the results of the operations of chartered vessels in the oceanic tuna fishery (Sudarsan el. al., 1991; FSI, 1992) and a bibliography of tuna fisheries in Indian seas (John and Bhargava, 1992). These publications have updated our information on the coastal and oceanic tuna fishery resources from the Indian EEZ

Minimum Legal Size proposed for commercially exploited marine finfish and shellfish resources of Tamil Nadu

Marine fisheries in Tamil Nadu have undergone tremendous change in terms of fishing pattern, fishing method, extension of fishing grounds, composition of fish catch and consequent increase in the total fish catch in recent years. The recent demand from industries involved in fish meal and fish oil encourages targeted fishing for by-catch resulting in heavy landing of low value by-catch in certain places along Tamil Nadu coast. These by-catch are often dominated by juveniles of many commercially important marine finfishes and shell fishes. So it warrants some caution and intervention. One of the methods to discourage the indiscriminate exploitation of juveniles is to impose a Minimum Legal Size (MLS) which is the size at which a particular species can be legally retained if caught. The advantage of a MLS is that it aids in the control of two major problems in the fisheries management, growth overfishing and recruitment overfishing either by increasing the minimum size of harvest or by increasing or maintaining the size of the spawning stock. The most common method of increasing the reproductive output through the use of size limits is to set the minimum size at which the females become sexually mature. As the individuals of a species do not attain sexual maturity at the same size, it can be a size at which higher proportions are mature

Fishery, population dynamics and stock structure of frigate tuna Auxis thazard (Lacepede, 1800) exploited from Indian waters

Auxis thazard, commonly known as frigate tuna represents an important group of coastal tuna species occurring in the Indian waters. The species is landed all along the Indian coastline and the major landing is along the south-west coast with Kerala contributing the most. The species is exploited by a variety of gears viz., drift gill nets, shore seines, ring seines and hooks and lines. Though there is recent information on the fishery and the exploitation status of Auxis thazard from Tuticorin (Kasim, 2002; Abdussamad et al., 2005) and Veraval (Ghosh et al., 2010), studies on the catch, population characteristics and stock estimates covering the entire coasts of India are lacking after the work of Silas et al. (1985) and James et al. (1993). These studies date back to two decades, after which there has been a change in the fishing pattern of coastal tunas throughout the country. Therefore, the present study was undertaken to provide an insight into the fishery, population dynamics and stock structure of A. thazard exploited from Indian water

Fishery, biology and stock structure of skipjack tuna, Katsuwonus pelamis (Linnaeus, 1758) exploited from Indian waters

Global catches of skipjack tuna have been steadily increasing since 1951, reaching a peak in 2009 at 25, 99,681 t (Fig.1). Most of the catches were reported from the fishing areas 71, 51, 61 and 34 (FA0, 2011). Globally skipjack tuna is caught at the surface, mostly with purse seines and pole and lines and to a small extent by gillnets, troll lines and longlines. Gears like purse-seine and very long gillnets enabled few nations to augment their production, whereas traditional pole and line nations suffered heavily

Fishery and bionomics of the little tuna, Euthynnus affinis (Cantor, 1849) exploited from Indian waters

Euthynnus affinis, with an average annual landing of 40,757 t during 2006-2010 formed the bulk (65.1%) of the total coastal tuna catch of the country. The fishery, biology, growth and stock structure of E. affinis was studied in detail. Hooks and lines, gillnets and purseseines were the major gears exploiting the fish. Fishery was sustained mainly by 1 - 2 year old fishes (34 to 50 cm). Size at first maturity was estimated at 37.7 cm and fecundity was 3,08,150 eggs. Spawning was observed round the year with peaks during July-August and November-January. E. affinis was found to be a nonselective generalist feeder foraging on fishes, crustaceans and molluscs. The length–weight is given by the relationship 0.0254 L2.889 with no significant difference between males and females. Age and growth were estimated using length based methods. The von Bertalanffy growth parameters estimated were L∞ = 81.92 cm, annual K= 0.56 and t0 = -0.0317. Mortality estimates were M= 0.93 and Z = 1.68 and F= 0.75 with the exploitation rate E=0.45. The maximum sustainable yield estimated was higher than the average annual catch indicating scope for further exploitation

Instance of mass fish mortality at Mandapam, South east coast of India

From the collected informations and data above information and the data, it appears that the cause offish mortality observed between 13th and 15th May, 1987 at the Palk Bay side of Mandapam was mainly due to the natural phenomenon resulted by the ecological changes restricted to an area of about 3-4 km* between the shore and the coral reef. It was possible that the phytoplankton blooms reported just before the phenomenon and its isolated occurrence immediately after the incidence, and the associated changes in the water quality, the mixing up of the polluted water drained from the Mandapam fish landing centre and its subsequent spread within the reef area due to the prevailing water current would have triggered off an anoxic condition in the water column causing stress in the environment and consequent mortality of the fishes. Further, the absence of any physical and biological symptoms as revealed by the examination of the dead fishes, their gills and the gut contents, and the absence of any report of untoward incidents on the consumption of the dead fishes excluded the possibility of the cause of the reported mortality due to poisoning, pollution or the use of explosives