The Sea Trout Project: Annual Report 2023

At the request of Havbúnaðarfelagið, studies of sea trout have been conducted with the aim of investigating when during the year the trout migrate to the sea for the first time and how well they thrive in the marine environment.
In 2023, the methodology was changed, and most efforts were focused on tagging sea trout and establishing an antenna monitoring system. The system records tagged trout as they swim past it. It is installed near the mouth of the Eiðisá river in Norðagøta. The results from this system will therefore shed light on when sea trout migrate to the sea and whether trout return to the river more frequently when lice levels in the fjord are high.
The work in which sea trout anglers submit scale samples and other information about the caught trout continued in 2023. The results showed that the trout in 2023 were in good condition and had few lice compared with previous years. However, this was not the case with regard to the proportion of trout that carried lice. As in previous years, sea trout had the highest lice loads from June to August, but in 2023, lice were reported on trout during winter for the first time. Nevertheless, there are still strong indications that sea trout de-louse in freshwater.