The traditional brown trout could be endangered by the release

The Environment Agency says the fish, which are not native to Britain and are aggressive when competing for food, could endanger traditional brown trout.

They escaped from Chalke Valley Trout Farm on the River Ebble at Broadchalke near Salisbury, Wiltshire, in June.

The trout will be fed to piranhas at Weymouth Sea Life Park in Dorset.

'Ecological damage'

Adam Davis, of the Environment Agency, said: "The River Ebble is a wildlife-rich tributary of the River Avon and a fine example of a native brown trout river.

"Unfortunately, the rainbow trout is a highly competitive, predatory species.

"It will actively compete for space and habitat, and will predate other species, either directly or indirectly, by taking their food source.

The fish will be fed to piranhas

"Their removal is necessary to protect our native wildlife.

"Many of these fish were destined for the table.

"We now need to remove them to prevent significant ecological damage and we are pleased that they're not going to waste and will benefit the animals at the Sea Life Park."

Otters, penguins and other animals at the sea life park will also be able to feast on the rogue fish.