Benchmark : Curious-looking lumpfish proving its worth in fight against sea lice

Nevertheless, they are unlikely to be the only method to use against the perennial parasite problem.

'While there's going to be a move towards cleaner fish, there's going to have to be a balanced approach,' agrees Ben, 'and there will still be a requirement to use targeted pharmaceuticals as well, and also mechanical treatments - because you're up against a challenge that is quite substantial.'

Indeed, the scale of the lice challenge in Shetland means that, according to Adam, it is wise to have a relatively high ratio of lumpfish to salmon - perhaps about twice the accepted industry standard of around 1:10 (ie one for every ten salmon).

'The last site we stocked had ten cages and the ratio of lumpfish to salmon varied - from about ten to 20 percent. We found those stocked with 15 to 20 percent were the most effective,' says Adam. 'As a result, I think it's best if we aim to stock all our sites at 20 percent [ie one lumpfish for every five salmon] initially, and then look to bring this down gradually, as they have an impact on lice levels over time.'