Bycatch threat to marine eco system, says expert

 
Delivering a key-note address at a workshop on ‘Bycatch—Its impact on marine fisheries’ organised by the Mangalore Research Centre of Central Marine Fisheries Research Institute here on Wednesday, he said that on an average bycatch constitutes 20 per cent of trawl landings in India. In 2009, MDF boats had discarded 14,837 tonnes of bycatch in Mangalore. About 50 species of finfishes and 20 species of molluscs form bycatch in Mangalore.

Stating that 20-80 per cent of low value fish landed by trawlers in India are juvenile fish, he said 6,600 tonnes of juvenile nemipterus species landed in Mangalore during 2009-10 catch. The loss by catching juvenile fish was 14.7 crore during 2007-08 in Mangalore. Given a chance to grow, they will contribute more in terms of catch and value.
The juvenile catch results in the collapse of fisheries, he added.

Dr Radhakrishnan said that the bycatch will have a social impact which will encourage the trade of trash fish and also encourage shrimp trawlers to fish in shallow water which will lead to rift with the artisanal fishermen.

The trawl fishing has an impact on eco system. It will change the seabed habitat structure.

Fishing down the marine food web exploitation of larger predatory fishes will imbalance the food web, he added.

He called upon the experts and scientists to identify an indicator species sensitive to fishing and then monitor their distribution and abundance.

In 2009-10, 14,837 tonnes of bycatch was discarded by the multiday trawlers in Mangalore.

No fishing zone

He said: “The government should seriously think of starting no fishing zones and marine sanctuaries to avoid bycatch and to preserve species of fish. The marine sanctuaries can also be developed into eco tourism spot.”

Public consensus is needed for minimising the bycatch. Night trawling should be banned. The amount of bycatch would be more during the night trawling, he informed.
Delivering a talk on ‘recent trends in marine fisheries of Karnataka’ Scientist Dr Prathibha Rohit said the fishing sector has changed from traditional to multicrore fully mechanised sector.

 Fish finding devises have undergone sea change with the usage of GPS, fish finders, net sonde sonar, improved engines. Purseseine is being replaced by trawl catchers in Karnataka, she added.

In his introductory remarks, Senior Scientist Dr A P Dineshbabu said that the workshop intends to focus on better utilisation of bycatch as well as reduction of discards by operational changes. It will help to enlighten the stake holders on the status of bycatch in Karnataka trawl fishery and highlight its possible impacts on long term sustainability.
He also presented a paper on ‘bycatch in trawl fisheries of Karnataka, present status, its impact and possible solutions.”

The workshop was inaugurated by Karnataka Fisheries Development Corporation Managing Director V K Shetty.