The spread of harmful algal blooms and marine pollution are a serious threat to the fishery resources of the Indian Ocean RIM countries.

The expansion of these algal blooms in the past 25 years is responsible for losses to the tune of $100 million a year in the region, N.R. Menon, School of Marine Sciences, Cochin University of Science and Technology (CUSAT) and Co-Chairman of Nansen Environmental Research Centre India, said.

Speaking at a session on ‘Harmful Algal Blooms of the Indian Seas’ in the workshop on Fisheries Management, he said that loss of production in fisheries, severe reduction in local or regional tourism, public illness and decline in fisheries-related business are the major economic consequences of harmful algal blooms.

Reasons



The possible reasons for the increase in algal blooms, he pointed out, are the natural processes such as circulation, upwelling and river flowand anthropogenic loadings leading to eutrophication, wind, weather and tidal or other hydrographic conditions related to the initiation of near shore blooms.

Transport of seed population to the coastal waters and dumping of wastages into sea are other major causes, he said.

Precautions should be taken while conducting cage culture by avoiding coastal areas where harmful algal blooms occur, he said.

Pollution



Endorsing similar views, N. Chandramohanakumar, Department of Chemical Oceanography, CUSAT, said that marine pollution is a serious issue which causes deterioration of fishery resources in the Indian Ocean.

Marine pollution will lead to destruction of habitat, acute poisoning by toxic wastes, adverse alteration of water quality and bacteriological and viral contamination.

Artificial reefs



By intensifying aquaculture in protected water bodies, fish resources that are facing deterioration can be preserved to a certain extent.

Steps should also be taken for improving the spawning channels or areas by creating artificial reefs, he said.

The 12-day workshop, organised jointly by External Affairs Ministry and Kerala University of Fisheries and Ocean Studies, is aimed at bringing together researchers and resource managers to review the status of fish stocks, existing resource database and management practices being followed and to propose appropriate follow-up actions.

>sajeevkumar.v@thehindu.co.in