Traditional fishing methods of Lakshadweep

Economy of the Lakshadweep islanders depends mainly on coconut farming and fishing. About 30-40% of the population are full time fishermen. Some of the fishing methods practised by the islanders are still traditional, Tuna forms the main established fishery of the island. Pole and line fishing is the most effective fishing method for surface tuna shoals. Most of the traditional fishing operations prevailing in the islands are unique and conducted during neap tides only.

Indigenous construction of fishing boats at Versova village in Maharashtra State

Versova, one of the 23 fishing villages in the district of Greater Bombay, is a major fishing centre. During the last three decades mechanisation of fishing boats received a tremendous boost in the state specially in and around Bombay resulting in higher income and gainful employment to fishermen. Indigenous construction of fishing boats at Versova contributes to the marine fisheries development. Inspite of certain constraints in construction activities, training of artisans in boat construction would ultimately help in the economic growth of the village.

A case study of the disappearance of Arius tenuispinis (marine catfish) in the vicinity of Visakhapatnam due to mechanised fishing

Visakhapatnam is on the eastern sea board of India (17 degree 40' N and 83 degree 15' E) having a continental shelf of 45 km width which is provided with a polychaete rich, silty clay sea floor to a distance of 15 km and beyond, from the shore. Repeated trawling by a large number of trawlers over an area of 900 sq.km (30 x 30) resulted in the hardening of the substratum to the extent of making it uninhabitable to the polychaetes and polychaete feeding fish. The shoaling and strictly demersal marine catfish, Arius tenuispinis, which is a prolific polychaete feeder on the fishing grounds off Visakhapatnam, has been on the decline since 1979. The catch rate of fish dropped from 9.7 kg/boat per day in 1979 to 2.6 kg by 1985-86. In the bottomset gillnets, the catch per net dwindled from 4.4 kg in 1973 to 0.04 kg by 1985-86. The species has virtually disappeared from the fishing grounds off Visakhapatnam and further north, as a results of the cumulative effect of overfishing with trawlnets and bottomset gillnets. It is further aggravated by the hardening of the sea floor on these grounds due to repeated trawling over a narrow zone.

The effect of mesh size on the fishing efficiency of sardine gill nets

The study deals with the effect of mesh size on the fishing power of gill nets. The authors have shown that there can be substantial difference in the out puts of sardine gill nets, of identical design and rigging, but of different mesh sizes, operated under the same conditions.

Preliminary experiments to evaluate the relative efficiency of different natural baits in line fishing

A series of experimental hand-line fishing operations were conducted off the Madras coast employing five different types of natural fish baits. Based on the total catch of fish per day of fishing under each type of bait used, a comparative study on the catching efficiency of the different natural fish-baits was made. The reaction of the fish to particular bait appears to be the result of a complex process. Live baits have the maximum catching efficiency as seen from the fish landings when live prawns were employed as the bait. The procurement of live baits is a serious problem to the fishermen and as such suitable artificial fish lures can be profitably employed.

Technical terms in fishing gear materials and gear fabrication

Papers dealing with technical terms in fisheries science are few. This paper however, covers only one or two aspects of the subject, namely fishing gear materials and fishing gear fabrication. Similar papers on other aspects are also planned. Short explanations or descriptions are also given wherever considered necessary.

On the use of different natural baits for sea-fishing in India

Rod and line, hand-line, trolling line and fish-traps are the different types of fishing gears wherein suitable fish baits are employed with a view to luring the catch. The coastal fishermen of India mostly use different types of natural fish-baits to catch fishes like Perches, Carangids, Sciaenids, Scombroids and Elasmobranchs. The reactions of the fishes caught to the different baits used are quite varied. Successful line fishing operations very much depend on the fish-baits. A detailed record of the variety of fishes caught, types of fishing and different baits used by the coastal fishermen of India has been made.

Prawn fishing by M.F.V. Jheenga in Bombay waters

The design and construction of the motor fishing vessel Jheenga of the Deep Sea Fishing Station of the Government of India, Bombay, the areas covered and the gear used by her in 1959-63 are described. The prawn catches in relation to the total catches, and their catch rates in different months in area 18-72 in Bombay region which was fished continuously during the five years period have been studied with a view to ascertaining their seasonal abundance. The results indicate the availability of the prawns in the region for the major part of the year from March to October-November. High catches with high catch rates forming high percentage of their abundance in total catches are obtained in July to October.

Trends in development in the prawn fishing technique in India: a review

The paper provides some background information about the developments in the prawn fishing technique. The important indigenous gear for prawns are the filtering type nets like the stake nets, boat seines and beach seines with bag. The only indigenous net, which can be compared in design with the modern bottom trawling gear, is the "Thuri Valai" of the Madras Coast. Prawns have also been reported from the catches of gill nets and cast nets. Dredges and beam trawls are simplest among the dragged gear. Even though several earlier attempts were made with the beam trawl, in 1959 season a detailed experiment was made to study the fishing features of this gear. The subsequent experiments conducted were for comparison with otter trawl, towing of 2 beam trawls one behind the other and the use of tickler chain. The initial experiments with otter trawls were mainly directed towards operational aspects. The experiments were to evaluate the effectiveness of fully mechanised and partially mechanised operation, the effect of extra buoyancy of floats and the use of tickler chain. Subsequent developments had been on the structure and design of prawn trawling gear. Effect of long wings and sweeps were tested. Catches of nylon and cotton nets were compared. The sizes of meshes of the cod-end have also been increased.

A preliminary account and review of the simple methods for determining the operational parameters of fishing gear, underwater, with notes on its application

An account and review of the simple methods for determining the operational parameters of fishing gear, underwater, such a tilt of otter boards (outwards or inwards, forwards or afterwards), vertical height of net, its horizontal spread, angle of divergence at bosom, spread between wing tips, angle of inclination of danlenos, butterfly, slope of legs and sweep-line has been given. The relationship of distance between the otter boards spread and the vertical height of net has been obtained as generally linear. The possibilities of regulating the vertical height of net (dependent variate) and spread of otter boards (independent variate) for increasing the fishing efficiency has been discussed. The angle of attack of oval shaped otter boards used during the operations still remain undetermined, however, it has been explained how the best angle of attack for increasing the efficiency of gear can be obtained by regulating the ratio of depth to warp for a given net. The inadequacy of the mere indices of catch per hour of trawling in comparing the relative efficiency of trawls in gear research studies has been indicated. The importance of estimating the operational parameters and its application to commercial fisheries depending upon the distribution pattern of fish and in gear research has been discussed. The efficiency of the jelly bottle method has been compared statistically with the observations made on the trawl gear underwater with instruments.

Standardisation and mass production of shrimp trawlers and other fishing boats in India

This paper deals with the existing fishing crafts, new vessel types, boat building programmes, their standardisation and mass-production in India.

Fishing gear and methods of the river Brahmaputra in Assam

Potentially the inland fishery resources of the country are of very high order. But the present level of their exploitation is far from optimum, mainly because of the inadequacies of the existing fishing gear and methods. There is vast scope for increasing the fish production from inland waters by improving the existing gear and methods. This would require a thorough study of the fishing gear and methods in vogue, of which very little is known at present. In the present communication the authors discuss the fishing gear and methods of the river Brahmaputra, in Assam, based on a survey carried out by them during January-February 1964. The survey covers a 640 km stretch of the Brahmaputra River, its important tributaries and connected bheels, from Dhubri to Dibrugarh. As a result of the survey about 19 types of fishing nets, which could be grouped into eight classes, were identified. The salient technological features of the gears and their methods of operation are discussed class-wise. The characteristics of the individual types are shown in tables. The materials used for gear and gear accessories, are briefly discussed. The classification and relative importance of different types of gear are examined. Besides, the influence of the ecological and topographical features of the river on the development of different types of fishing gears, is also discussed.

An interpretation of the data from "The effect of mesh size on the fishing efficiency of sardine gill nets"

The paper "The effect of mesh size on the fishing efficiency of sardine gill nets" [K.M. Joseph and A.V. Sebastian, Fish. Tech; 1(2), 180-182 (1964)] marks an important step in the progress of fisheries technology and biology in India.

Preliminary experiments on electrical fishing in fresh watter [i.e. water]

Fishing using electricity is a new technique and is still in the experimental stages in many of the advanced countries. While no published records are available in India, considerable work has been done in Germany, United States, Canada, and United Kingdom. These papers mainly deal with the behavior of the fish in the electrical field, the physiological effects of electrical current on fishes, methods of electrofishing, electric fencing etc. The following experiments on electrical fishing were conducted with a view to studying the distribution of electrical field when an alternating current is passed through two fixed electrodes in fresh water and to study the reaction of different fresh water fishes to the field.