We are currently in the final days of the 2020 smolt migration, where we have detected more than 1,000 tagged salmon smolts heading to sea, and this morning the first PIT-tagged adult of the year returned to the Frome. In fact, the first two tagged adult salmon were detected within five minutes of each other at East Stoke!
The first fish was tagged in the River Hook in September 2017 in the very headwaters of the Frome catchment, and the second fish was tagged in the lower middle river, also in September 2017.
Every autumn the GWCT, in collaboration with Cefas, PIT tags 10,000 juvenile Atlantic salmon in the Frome catchment. These PIT tags enable us to detect the tagged fish when they migrate past our PIT tag antennae in the Frome catchment, both on their way to sea as smolts in the spring and when they return from their marine journey as adults.
Atlantic salmon spend between one and four years at sea before returning to their native river to reproduce. Generally speaking, individuals that have spent two or more years at sea return during spring or early summer, whereas individuals that only spent one year at sea will return later in the summer.