As the world celebrates World Oceans Day on Monday, scientists at the Marine Products Export Development Authority’s (MPEDA) extension wing, NETFISH, are ready to make bottom trawling more environment friendly and less destructive.
“Bottom trawling is the most destructive method of fishing ever invented,” said an MPEDA scientist on Sunday. But, the new fishing gear promises to considerably reduce by-catch and cut environmental pollution.
Experiments with the new fishing net off the coast of Munambam showed considerable reduction in the catch of juvenile fish and other marine animals.
The new gear also helped reduce diesel consumption by two litres per trawling hour.
The new fishing gear, which was tested over two days on March 18 and 19, comprised a trawl net cod-end of 25-mm square mesh instead of the conventional diamond-shaped cod-end of the same mesh size. It was found that the square shape of the cod-end helped juveniles escape easily once they were trapped in the net, said the scientist.
“The substantial reduction in by-catch saves time for the fishermen, who otherwise spend a lot of time on sorting the fish catch,” said the scientist. The conventional method of bottom trawling traps even sand from the bottom of the seas along with marine organisms and juveniles of fish, squid and cuttlefish.
It is estimated that by-catches and juveniles make up between 50 and 70 per cent of the total catch when the conventional trawling net is used.
The new fishing gear, first developed by the Central Institute of Fisheries Technology in Kochi for trawl boats, will be introduced to trawl boat operators on Monday at a function at the Munambam fishing harbour.
The trawl boat that was used for the experiments had a 450-hp engine and a 100-metre long net. The cod-end of the net was seven metres long.
The MPEDA scientists are set to experiment the same net for shrimp trawling after the monsoon trawl ban.