Summary of Abstract Submission

Abstract Submission No. IO50-03-0043PresentationOral

FISHERIES BY CATCH AND ITS IMPACT ON MARINE BIODIVERSITY IN THE ECOLOGICALLY FRAGILE GULF OF MANNAR BIOSPHERE RESERVE.

Dr. RAVEENDRA DURGEKAR*1, Dr. ULHAS G NAIK1

1 DEPARTMENT OF MARINE BIOLOGY, KARNATAK UNIVERSITY, INDIA

ABSTRACT :

The work was carried out for the period of one year form Nov 2010 to Oct 2011 in the Ecologically Fragile Gulf of Mannar Biosphere Reserve. The outcome of the project was rapid assessment of over exploitation of fishing resources in the Gulf of Mannar, Tamil Nadu, India. A total of 416 species of marine organisms which were caught in trawl net, of these 157 species were targeted, 248 species of non-target and wheras 25 species was discarded. The trawling operations were generally carried out around the corals surrounding the 21 islands around the area; almost all are losing corals species, which is a sign of great concern as this area is rich in marine fauna. In the present study period it was noted that 75% of the total catch were non-targets and around 15% of the total catch were discarded back sea. Juveniles formed almost 60% of the total catch, which is the most alarming issue. Most of the non-target species were seen to be threatened and banned species. The gears that are operated by mechanised trawlers in the Gulf of Mannar area are prawn trawl, bull trawl, finfish trawl and the chank trawl. Particularly, Chank trawl was found to use rigid foot ropes consisting of iron chains that can damage the sea floor where it was used. Non-targets are unconditionally caught and sold to get more revenue. It is summarised from the present study that ane endangered species like sea cucumber, seahorse and some endangered fishes like sharks (especially hammerhead sharks), rays and catfishes (most of them juveniles) were found caught in huge quantities in the trawl net; surprisingly we could see these species were sold as bycatch because most of them were juveniles. Even the gastropods and bivalves, e.g. Murex spp., Cardium spp., etc., which are nearly extinct from these coasts are caught as incidental bycatch and brought for some reasons that are not beneficial to anyone.