A leading expert on Marine Ecology has written to the Minister for Food, Agriculture and the Marine to warn him of the potential danger of sea lice posed by offshore salmon farms.
May 16, 2013
by Conor Harrington
A leading expert on Marine Ecology has written to the Minister for Food, Agriculture and the Marine to warn him of the dangers of sea lice emanating from offshore salmon farms.
Mark J Costello, who is an Associate Professor at the Leigh Marine Laboratory in the University of Auckland, New Zealand, said he was compelled to write to Minister Simon Coveney due to misleading reports as to the risk of sea lice in the media.
In his letter to Minister Coveney, Prof. Costello said that salmon lice emanating from farms have been linked to mass fatal parasite infestations called 'epizootics ' on wild salmon, trout and their relatives in Ireland, Scotland, Norway and Canada.
“They have only been reported in locations with salmon farms,” wrote Prof. Costello, although he noted that “correlations do not prove cause”.
Prof. Costello, who studied for his Bachelor's Degree at NUI Galway, further noted that, when large-scale sea lice infections occur, they can be difficult to control and that wild fish up to 30km away from a farm could be infected by lice from the farm.
“Sea lice...have proven difficult to control on farms, especially large farms, because it is difficult to treat all fish simultaneously against the parasite, and where several farms occur in the same area due to cross-infection,” wrote Prof. Costello.
Prof. Costello, a former Chief Editor of the European Register of Marine Species, said that, if there were a million fish on a salmon farm with one egg-bearing louse each, the farm could release up to 500 million lice larvae.
“A key consequence of this is that on large farms, it is possible to keep the number of lice below what is harmful to the farm fish but they may still be producing a lot of lice larvae,” he said.
The harmful effect of sea lice has been one of the main bones of contention in the ongoing debate over proposals to locate a €60 million organic salmon farm in Galway Bay, off Inis Oírr.
Bord Iascaigh Mhara (BIM), the State body that is applying to Minister Coveney for a licence for the salmon farm, has argued that the risk posed by sea lice is minimal, while anglers' groups, environmental organisations and BIM's fellow State agency, Inland Fisheries Ireland, have maintained that the risk posed by sea lice to wild fish stocks is significant.
Reacting to Prof. Costello's letter, Niall Greene of Salmon Watch Ireland called for an independent review of the Galway Bay salmon farm proposal.
“Minister Coveney cannot ignore the mounting evidence that BIM have totally misrepresented the threat posed to wild salmon by sea lice and farmed salmon escapees emanating from the proposed Galway Bay farm,” said Mr Greene.
Responding to the letter, a spokesperson for the Department of Agriculture, Food and the Marine told the Galway Independent that the Department’s policy on sea lice management was “strictly evidence based”.
“The control protocols are operated by the Marine Institute on behalf of the State and are more advanced than those operated in other jurisdictions,” said the spokesperson.
“The control protocols have been the subject of detailed investigation and testing by the EU Commission which has confirmed that it regards the sea lice protocols operated in Ireland as representing best practice internationally,” he added.