There's no escaping the benefit of cage standards

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Associate professor Tim Dempster, of the Sustainable Aquaculture Laboratory at the University of Melbourne and the editor-in-chief of Aquaculture Environment Interactions, questions whether the collapse of Cooke Aquaculture Pacific's farm in Washington State would have occurred if other countries had adopted Norwegian and Scottish standards.

The recent dramatic images of the breakdown of an Atlantic salmon farm on the Pacific coast of the United States are startling. Square steel cages in a tangled mess with the fate of the 305,000 fish they contained as yet uncertain. Some have been recovered from the cages, some will have escaped. Norway suffered a similar spate of escapes due to whole cage or farm breakdown over a decade ago. Norway still suffers escapes from salmon farms, but farm or whole cage breakdown has disappeared from the causes of escape. How did they fix it?

From 2009-2012, the European Union’s Prevent Escape project led by myself delved deep into the causes and consequences of escapes from aquaculture, with the purpose of identifying how we could better stop escapes.

Proper design

As part of the project’s work, a detailed analysis of escapes in Norway Atlantic salmon production revealed that after the Norwegian technical standard (NS 9415) for the proper design, dimensioning and operation of for sea-cage farms was implemented in 2006, the total number of reported escaped Atlantic salmon declined dramatically, despite the total number of salmon held in sea-cages increasing by greater than 50 per cent during this period (Jensen, Dempster et al. 2010; Aquaculture Environment Interactions).

What did the introduction of the technical standard do? Well, it encodes the type of technology (cages, mooring systems etc.) that can be used at farming sites depending upon the maximum forces those sites experience in a once-in-50-year storm or severe weather event. Prior to the technical standards introduction in Norway, big escapes happened due to the breakdown of cage structures and mooring systems. The technical standard basically eliminated complete farm failure as a cause of escape.

Lagging behind

Based on the success of this measure, the Prevent Escape project recommended that policy-makers worldwide introduce a technical standard for sea-cage aquaculture equipment coupled with an independent mechanism to enforce the standard. We were pleased to see that Scotland followed with a new technical standard in 2015, yet other producing nations are still lagging behind on this key mechanism to prevent escapes.

It leads us to ask the question, if the United States had introduced a legislated technical standard that reflected best practice and drew upon the long success of the Norwegian technical standard, would this massive escape ever have occurred?