Adult Brown trout spend much of the year feeding in the larger channels of the Tweed system. However, throughout October and November, Brown trout will leave their feeding grounds and migrate upstream to spawn. Which spawning grounds trout come from and how far they travel within the Tweed catchment are important management questions for the trout fishery to consider. To help to answer these questions, the Tweed Foundation has been tagging and tracking adult Brown trout to monitor their movements throughout the Tweed catchment.
Since 2018, the spawning migrations of 27 Brown trout (all between 16 and 24 inches in length) have been monitored. The trout were tagged with small, acoustic tags that send out regular sonic ‘pings’ containing a unique identification code. Tracking receivers are strategically located along the main stem of the Tweed which record the identification codes of any tagged trout that swims past, allowing us to record the movements of each fish during their spawning migrations.
There are two components to our Trout Acoustic Tracking project: tracking post spawning migrations in trout as they leave a burn in the Upper Tweed, and tracking spawning migrations in trout caught within the Gala Angling Association’s section of the River Tweed.