Impact of non-selective gears on kingseer, <i style="">Scomberomoruscommerson </i>fishery in Karnataka

Abstract

Catch-length analysis of kingseer, <i style="">Scomberomorus commerson</i> from motorised (drift gillnets) and mechanized (purseseine and trawl) fishing operations in Karnataka from 2004 to 2009 was analyzed. Length composition varied in different gears with smaller fishes being predominant in trawl (59.6%) followed by purseseine (39.2%). In drift gillnet young ones formed only 1.2%. Thompson and Bell model predictionsof kingseer stock in the multifleet fishing scenario were attempted to examine the effects of the motorized and mechanized efforts on the maximum economic yield (MEY) by simulating different effort combinations. Theoretical economic yield obtainable from the drift gillnet fishery alone was obtained at 60% of the current F is (48.1%). This yield is much higher than those obtained from the present multi-gear fishery. When the drift gillnet and purseseine efforts are varied while avoiding the exploitation of juveniles in trawl, 28% increase in MEY is predicted at Rs. 1,087 million. Hence a reduction in the effort expended, by restricting trawl and purseseine operations and retaining the large meshed drift gillnets (65-170 mm) at MEY levels will result in maximum economic returns and for sustainability.