As Derek has observed it's nothing new having 'exotic' visitors, but I'm not sure I welcome their presence in the long term.
Following their introduction in the Soviet era (in part to create a viable fishing community) these fish now have naturalised populations in the Barents Sea. Close to home there are now small but viable populations in Norway and gradually there is evidence appearing that these populations are spreading.
Not unreasonably I might suggest that it's like the spread of Brown Trout across the British Empire where, after being introduced, the Brownie demonstrated an almost unrivalled ability to adapt incredibly successfully to new environments and then expand into neighbouring systems. You only have to look at some of the more interesting adventures available to you in the southern hemisphere where there were
no native Salmo species until we introduced them to know that the potential is there..... are they an invasive species there
Yes, but there again they are of such economic importance for sport fishing and tourism that they're not necessarily considered in those terms.
Do we really want a repeat of that in the UK
Well, what concerns me more this year is the numbers of these fish that have entered our rivers. If we are catching them there are far more of them - it's that simple IMHO. They might (eventually) be able to establish self-sustaining populations in the UK and we already know that there can be dire consequences on native species by introducing a 'radical element' to an environment.
Although the self-sustaining populations of these invasive Salmon species have yet to take hold in the UK (as far as we know) there is a precedent in the UK for non-native North America species establishing a population. The Rainbow Trout has spawned successfully in rivers and perhaps the most successful or renowned population are the Rainbows of the River Wye in Derbyshire.
Whilst the Rainbow and the Brown co-exist there, the Atlantic and Pacific Salmon are not found naturally together. It follows that you cannot have an invasive Salmon species establishing themselves without there being an impact on the native species and biodiversity, for example the loss of all Spring fish as their spawning area gets taken over, or maybe an entire tributary becoming home to the invasive species etc.
Do we need another species to 'spice things up' for the rod angler
Well, we used to have the Sea Trout. We should probably do more to nurture them first
Is there evidence to suggest that these 'aliens' pose no threat
Hmmm....personally I think not. I'd say the evidence that they are a serious threat is there for us all to see
if we chose to look. So these fish are a very real threat in my book and I am very firmly in the camp of 'knock them on the head first and ask questions later'.
H
