OCEANOGRAPHICAL AND FISHERIES RESEARCH IN INDIA 297 



the development of marine fisheries. It is natural that in connection 

 with fisheries programmes a considerable amount of interest was also 

 evinced in the further pursuit of oceanographical studies as an aid to 

 the proper exploitation of marine fishery resources. A very small part 

 of biological and chemical studies as a necessary ancillary to the de- 

 velopment of fishery investigations was initiated in 1948 when arrange- 

 ments for the systematic collection of hydrological data at selected 

 fishery centres were made. These attempts to obtain hydrological data 

 have been purely from the standpoint of fishery work and it cannot be 

 said that they have been carried out in any systematic manner in the 

 absence of a Fishery Research Vessel for regular cruising. 



It is well-known that the arrival and departure of shoals of fish in 

 any definite area are largely governed by their movements connected 

 with their feeding and spawning habits, which are most intimately 

 related to the physical and chemical properties of the sea water in which 

 the shoals are located. In the sea there are periodical fluctuations in 

 the physico-chemical conditions which may be annual, seasonal or even 

 diurnal; these fluctuations are the combined results of the action of 

 various meteorological and hydrodynamical factors. In addition to these 

 more or less normal variations there may also be abnormal variations 

 caused by geophysical disturbances or by factors unknown to us at the 

 present time. A very systematic approach to these various problems is 

 necessary to obtain a correct picture of sea fisheries of the Indian coast, 

 which are largely seasonal and some of which, like sardines, show large 

 variations from year to year. 



Indian marine fisheries are largely seasonal in character and the 

 causes governing the movements of shoaling fish and the reasons for the 

 failure or shift of seasons of a given fishery are at present unknown. 

 Similarly the fishing grounds have not been charted, though a beginning 

 has been made in this direction for areas around Bombay. The area 

 now exploited for sea fishing includes only the narrow coastal zone of 

 five to six miles from the shore. Power vessels to exploit the off-shore 

 fisheries have begun operations on a pilot scale in Bombay under the 

 aegis of the Government of India and in Calcutta by the Government 

 of West Bengal. In the not too distant future, it is expected that more 

 vessels will be put into operation from different centres like Cochin, 

 Madras and Visakhapatnam. The work of exploration of off-shore 

 fishery resources and the charting of fishing grounds is one which calls 

 for help from oceanographical studies as data on movements and com- 

 position of the water masses would be extremely useful. 



