Freshwater Arctic charr are restricted to cold water lakes and rivers of the northern hemisphere, including in Scotland, and are considered to be the UK’s most vulnerable salmonid due to their dependence isolated cold-water lake habitats, which are rapidly warming outside the tolerance of the species.
Now researchers at University College London and Queen Mary University of London, funded by the Fishmongers’ Company’s Fisheries Charitable Trust and collaborating with the West Sutherland Fisheries Trust and biodiversity monitoring company NatureMetrics, have verified the presence of this hard to catch species using new environmental DNA sampling methodology.
Results of the survey in North West Scotland have revealed that Arctic charr are present in Loch na Mucnaich and Loch na selig, two sites where there had only ever been anecdotal evidence that the fish was present. The study further confirmed presence in locations where the fish was last officially recorded over 60 years ago, including Loch Lon na h-Uamha.
These findings will aid future plans for conservation prioritisation, as the temperatures in European lakes are predicted to rise 3-4 degrees towards the end of this century, pushing cold water fishes such as Scotland’s’ Arctic charr closer to the limits of their thermal ranges.
Dr Joanne Littlefair, who led the work from the Department of Genetics, Evolution and Environment at University College London, said “it has been very satisfying to contribute to conservation issues around Britain’s spectacular freshwater fishes while training the next generation of budding scientists in conservation focused research and monitoring.”
The project, undertaken by intern Tianna Hewitson, has now been added to the permanent scientific record through a publication in the Journal of Fish Biology.
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