Biology of commercially important penaeid prawns of Goa Waters

Abstract

Recruitment of <i>Metapenaeus dobsoni</i> from the estuary to the exploitable stock occurred at 50-60 mm size as against 70-80 mm for <i>M. affinis</i> and 80-90 mm for <i>Penaeus merguiensis</i>. Seasonal and monthly variations in recruitment were discernible. Breeding population of these species also showed monthly and seasonal fluctuation. In <i>M. dobsoni</i> and <i>M. affinis</i>, maximum number of gravid females was recorded during postmonsoon season while in the case of <i>P. merguiensis</i> and <i>P. stylifera</i>, it was during the premonsoon season. Relative condition factor was invariably > 1 for those size groups which had more number of mature females. The gut contents of these species suggested that <i>M. dobsoni</i> was essentially a detritivore while the other 3 species were omnivores.