Journal of the Marine Biological Association of India

Spawner-Recruit distribution of Penaeus indicus in Parangipettai coastal ecosystem.

Volume 29 Issue 1&2

P. Subramanian

Abstract

Tamil Nadu ranks third in marine prawn production in India. Prawn fishery in Parangipettai Coast is considered the best among the east coast of India. The Indian white prawn Penaeus indicus and Tiger prawn Penaeus monodon are the commercially valuable components harvested from both estuarine and marine environments. Present study gathered informations about population distribution and abundance of different stages of P. indicus both from marine and estuarine phases. Among marine prawn production P. indicus contributes 46.18% and 56.18% in the estuarine production. The adult P. indicus exhibited high fecundity. Naturally they spawn in operi sea, far away from the shore, but within the continental shelf. The hatched out nauplius and protozoea are planktonic and marine in habitat. The mysis and postlarvae were migrated mainly during postmonsoon and summer seasons, to the inland brackish water such as estuary, backwater and mangrove along with tidal currents, where they nourished for about 6-9 months as juveniles (upto 120 mm), while approaching maturity they migrated back to sea for breeding and spawning. From the manipulation of field data it was evident that about 14 months are required for a postlarvae to become a viable spawner. The peak value of mean 'ATn' between 105 mm and 115 mm length group indicates the approaching maturity of P. indicus and other five peaks between 130 and 175 mm length group reveals five spawning activities and the declining of peaks reveals the subsequent senility. From the length-weight relationship it was evident that for a given carapace length, male prawns possessed a greater total length and weight than female counterparts.

Date : 31-12-1987