Stock assessment of marine catfishes of India

The marine catfish fishery of India during 1979-88 laid special emphasis on the stock and exfdoitation of two major species Tachysurus thalassinus and T. tenuispinis. These together constituted about 50% of the total catUsh landings of the country. Catfish production registered increase in the 1970-89 period, but the high fishing pressure in the mechanized trawl and purse seine sector resulted in non-judicious harvest of spawnets or brooders, eggs or embryos and juvenile or sub-adults of catfishes. Because of this, the yield of both the species suffered setback in the late eighties at most of the fishing centres. The exploilaticn level of T. thalassinus was 0.88 at Veraval, 0.85 at Cochin and 0.84 at Visakhapamam with corresponding Emax of 0.72,0.72 and 0.50. In Gujarat, Kerala and Andhra Pradesh the exidoitation of this species exceeded the annual average standing stocks. The exploitation rate <^ T. tenuispinis was 0.61,0.79 and 0.65 at Veraval, Mangalore and Cochin respectively. The corresponding Emu was 0.74,0.51 and 0.66. The exploitation was higher than the aimual average standing stocks in Gujarat, Kamataka and Kerala. The possible management strategies and remedial measures are discussed. Marine catfishes are widely distributed in the tropical Indo-Pacific region and are domi­ nant in the fish landings along the Indian coast. The estimated potential yield of marine catfishes is 123 000 tonnes and the annual average catch (1980-89) around 54 500 ton­ nes. They occur all along the coast up to a depth of 80 m, with particular dominance in muddy bottom areas, either in small aggrega­ tions or in large shoals. The adult populations ascend vertically and horizontally for feeding and breeding. This group forms a significant Present address: 'Senior Scientist, Scientist (Selecticn Grade).