Biology of commercially important penaeid prawns of Goa waters

Abstract

Recruitment of Metapenaeus dobsoni from the estuary to the exploitable stock occurred at 50-60 mm size as against 70-80 mm for etapenaeus affinis and 80-90 mm for Penaeus merguiensis. Seasonal and monthly variations in recruitment were discernible. Breeding population of these species also showed monthly and seasonal fluctuation. In Metapenaeus dobsoni and Metapenaeus affinis, maximum number of gravid females was recorded during postmonsoon season while in the case of Penaeus merguiensis and Penaeus stylifera, 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 Metapenaeus dobsoni was essentially a detritivore while the other 3 species were omnivores