- Minister Simon Coveney, Donal Maguire of BIM and Richie Flynn of IFA have all recently claimed sea lice do not affect wild salmon populations.(1,2,3) Yet, it is well established fact that they do. Indeed, current government policy requires all salmon farmers constantly monitor and treat their salmon for lice due to the considerable threat they pose.
Interestingly, these claims come just as BIM is applying for a license for a salmon farm in Galway Bay that is so vast it would double Ireland’s farmed salmon output. And, while we in Bantry Bay still await the decision on the proposed Shot Head salmon farm.
In all cases, officials quote a research paper by the Marine Institute which states ‘The results of this study would suggest that infestation of outwardly migrating salmon smolts with the salmon louse was a minor component of the overall marine mortality in the stocks studied’.4 However, the way the data is presented in this paper is curious.
Further inspection of the raw data indicates that sea lice emanating from salmon farms causes a significant problem. Table 2 in the report shows that the average rate of return for smolts treated to protect them from sea lice is 7% (meaning 93% of smolts are lost to other causes).(4) Meanwhile, average survival for untreated smolts is 6.3%. To say an average loss of 0.7% from sea lice is small compared with 93% loss to other causes whilst young salmon are at sea is true – but irrelevant. What is relevant is that sea lice cause roughly a 10% decrease in numbers of sea young salmon returning (the difference in return rates of 7% and 6.3%). This is a significant figure, showing quite the opposite of what the officials appear to be claiming.
Another recent research study by Inland Fisheries Ireland showed treated smolts are 1.8 times more likely to return, and that ‘sea lice larvae emanating from farmed salmon may influence individual survivorship and population conservation status of wild salmon in these rivers.’(5) This figure suggests salmon farms could cause a 44% reduction in unprotected wild salmon populations that are exposed to sea lice. Not just a significant figure, but a deeply worrying prospect for Ireland’s wild salmon stocks and angling businesses.
On top of these two studies, a recent three country meta-analysis, which combined the results of a number of studies including one in Ireland, showed wild salmon populations decreased by 50% in areas with salmon farming.(6)
In fact all the research cited shows sea lice have a significant impact on wild salmon in spite of every effort to control these infestations.
“It would seem officials are using statistics as a drunken man would use a lamp post – for support rather than illumination” said Save Bantry Bay spokesperson.
So, again, Save Bantry Bay is requesting the Government implement the recommendation of the 1994 Sea Trout Working Group which states ‘Until further advances are made in this direction, a precautionary approach dictates that it would be prudent to avoid siting new fish farms or increased salmon farm production (above existing licenced tonnage limits for operations) within 20km of a sea trout river mouth.’ (7)
Sadly, it seems dismissing research is not a new thing for those promoting salmon farming. When first requesting the recommended 20km threshold be implemented, Save Bantry Bay, saw Simon Coveney, Minister for Agriculture, Food and the Marine respond by dismissing (8) the Report that made the recommendation7 as flawed on the basis of two later Reports published in 1997.(9, 10) Having examined these subsequent reports they do not actually contradict the original findings but seek only to have further research conducted. This research was indeed undertaken, and is published in the form of the very paper mentioned earlier by Inland Fisheries Ireland which suggests 44% losses of wild salmon to sea lice.(5)
“If Ireland wishes to prevent further collapse of valuable wild trout and salmon stocks, and maintain its biodiversity and angling industries, such misrepresentation of the facts must stop.” says Alec O’Donovan, Secretary of Save Bantry Bay.
10 June 2012
For further information contact:
Alec O’Donovan, Secretary, Save Bantry Bay 087 7949227 (mobile)
Tony Lowes, Committee Member, Save Bantry Bay 027 74771 (office) 087 2176316 (mobile)
4. Impact of early infestation with the salmon louse Lepeophtheirus salmonis on the subsequent survival of outwardly migrating Atlantic salmon smolts from a number of rivers on Ireland’s south and west coasts. D. Jackson , D. Cotter, N. ÓMaoiléidigh, P. O’Donohoe, J. White, F. Kane, S. Kelly, T. McDermott, S. McEvoy, A. Drumm, A. Cullen; Aquaculture, Volume 319, Issues 1–2, 1 September 2011, Pages 37–40
5. Evidence for sea lice-induced marine mortality of Atlantic salmon (salmo salar) in western Ireland from experimental releases of ranched smolts treated with emamectin benzoate. P. Gargan, G. Forde, D.J.F. Russell, and C.D Todd, Canadian Journal of Fisheries and Aquatic Sciences, Vol. 69, No. 2, Feb. 2012.
6. Ford, J.S. and Myers, R.A. (2008). A global assessment of salmon aquaculture impacts on wild salmonids. PloS Biology, Vol. 6, No. 2, Feb. 2008.
7. Fisheries Research Centre, Abbotstown (1995) Report to the Minister of the Marine, Sea Trout Working Group 1994. Published by The Stationary Office, Dublin. Appendix 5 of the ‘Report of the 1994 Sea Trout Working Group’ (published 1995)
8. Department denies it suppressed ‘flawed’ report’, Irish Examiner Friday May 4, 2012
9. Sea Trout Monitoring Programne Independent Evaluation, Dr. Ian G. Cowx, University of Hull, May 1997
10. Analysis of the Independent Evaluation of the Sea Trout Monitoring Programne, Brian J Rothschild, University of Massachusetts, May 1997