THE Environment Agency is undertaking a programme of trapping salmon on the River Severn and removing their eggs for propagation. The resulting offspring will then be used to restock the UK’s most important salmon river.
This is being carried out at the Agency’s newly refurbished hatchery at Clywedog. The building was refurbished in 2002 and the hatchery was re-opened in 2003 after a funding contribution from Severn Trent water.
Once the brood stock have been caught, they will be transported to the hatchery where the female fish are encouraged to produce eggs. These eggs are then fertilised and placed in incubators until they hatch. The brood fish are then returned to the river of origin.
Once hatched, some of the young fish are stocked in the river almost immediately and the remainder are retained and fed for two to four months, making them larger and stronger. The facilities at Clywedog allow fish to be kept for a further eight to nine months, when they are stocked as immature adults. Doing this allows them to be microtagged, enabling the Agency to participate in marine survival studies. The Agency is expecting to stock out 250,000 fish in this first year of operation following refurbishment.
A hydroelectric unit at the dam provides power to the hatchery, with the reservoir also supplying clean water at a constant temperature. The hatchery is looked after with the help of Severn Trent Water staff. The newly refurbished hatchery will allow the Agency to double the numbers of young salmon it can breed and restock to the Severn.
Speaking about the project, Area Environment Manager David Throup says: “The River Severn’s salmon population has played an important part in the river’s history. The salmon also important to local tourism, drawing anglers from all over the country to fish the waters.”