As part of my Department’s sea lice control strategy a series of treatment trigger levels have been specified to ensure that lice control on offshore salmon farms is optimised. This management regime has been very successful in reducing lice infestation levels nationally. Treatment triggers during the spring period are set close to zero in the range of from 0.3 to 0.5 egg bearing females per fish and are also informed by the numbers of mobile lice on the fish. Where numbers of mobile lice are high, treatments are required even in the absence of egg bearing females. The mechanism for requiring treatments is to issue a notice to treat where appropriate.
In the case referred to by the Deputy, the lice levels on the 11th of April were 0.47 ovigerous females and a total mobile count of 2.25 lice per fish. This is within the range where a notice to treat can be issued. A treatment regime was in place and no notice to treat was required. At the subsequent inspection on the 30th of April lice levels had reduced to 0.27 ovigerous females and a total mobile count of 1.16 respectively. These are well below any treatment trigger levels and reflect the efficacy of the treatment undertaken by the company.
As a general point, the sea lice controls operated by the Marine Institute, on behalf of the State are more advanced than those operating in other jurisdictions and are regarded by the E.U. Commission as representing best practice internationally.
