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Record Algae Blooms Linked to Fish Farms

04 September 2012, at 1:00am

IRELAND - Record toxic algae blooms continue to close shellfish harvesting in the south west of Ireland are caused in part by the waste from fish farms. The local action group set up to oppose the expansion of fish farming, Save Bantry Bay, has drawn attention to the fact that fish farms are responsible for far more nitrogen and phosphorous in our coastal waters than sewage from major towns.

Using statistics contained in the Environmental Impact Statement for the proposed Marine Harvest salmon farm in Shot Head Bantry Bay, SBB points out it will discharge the equivalent nutrients of a town ten times the size of Bantry itself.

Bantry, Glengarriff, Gearhies, Adrigole, Castletownbere, Ardgroom, Kilmakilloge and Dunmanus shellfisheries are all included in the most recent closure notices from the Marine Institute due to the danger of contaminated produce. Some of these closure orders have been in place for almost three months. Toxic algae blooms are fed by excessive nutrients entering the water.

The charge is supported by numerous scientific studies, including UNESCO reports which confirm that fish farms can make localised blooms worse. Unlike on land where controls would be required, these farms discharge the fish faeces directly into the open marine environment.

The Marine Institute has issued continual warnings this summer as there is a real risk to human health for those who harvest wild shellfish. Many visitors to these polluted areas are unaware of the problem as there may be no visible sign of the algae blooms.

In 2008, the harvesting of mussels in Bantry Bay by one company led to a product recall in three countries and severe illness in more than 300 people in France and America. Such situations can have a devastating effect on the reputation and profitability of seafood products as well as damaging Irelands international green image.

SBB supports fish farming but only in Closed Containment Systems. These systems allow total control of all inputs and outputs. All waste is collected and treated, and the sea does not become polluted. A scoping letter was recent issued by the operators of the first proposed commercial scale closed containment salmon farm in Europe which is proposed for Bantry Bay.

In a statement issued on the release of the last closure orders by the Marine Institute, SBB said While fish farming is not the only cause of the record breaking blooms, the scientific evidence makes it clear that open pen fish farming in these Bays with their poor circulation of water must come to an end.

The question is, will Irelands government take note and become the leader in the next generation of fish farming technologies or will the Department of Fisheries current proposals for more than 300 per cent expansion continue, fuelling further algae blooms with the risks to health and Irelands reputation?

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