Weevils to stop invasive ferns in Lincolnshire rivers
Thousands of weevils are being released into a Lincolnshire river to stop the spread of a fast-growing water fern.
Azolla, also known as the fairy fern, is currently growing in the Maud Foster Drain in Boston and can double in size every four to five days.
If left, the invasive plant can form mats up to 30cm (11in) thick, crowding out native wildlife.
The weevils are being released near Cow Bridge, an Environment Agency (EA) spokesperson said.'Control its spread'
Debbie Sylvester, the EA's operations delivery team leader, said: "Azolla grows extremely quickly and can completely cover the water's surface.
"These weevils eat only this plant and should help control its spread."
Azolla was first introduced into the UK as an ornamental exotic from the Americas in the 1800s.
The EA added invasive species cost the UK economy an estimated £1.7bn every year.
Weevils were used successfully last year to control the weed on the River Till and River Witham, near Lincoln.