Weevils save the day in battle against invasive pond weed
An alien plant was proving to be a big problem on a pond at the Tees Valley Wildlife Trust’s Portrack Marsh Local Nature Reserve. The floating pondweed plant called water fern or “Azolla” had completely covered the surface of the pond choking it up leaving no areas of open water. It had probably been carried to the pond on bird’s feet from another garden pond.
The solution to the problem was both interesting and bizarre. It came through the post from a Bio-Science company in the form of three small plastic tubs containing hundreds of crawling, weevil insects each no bigger than a pinhead.
Becky Stanley, “Wild Youth Officer” from the Wildlife Trust, and her volunteers released the weevils around the edge of the pond, where over the next few weeks they set about munching their way through the pondweed a free lunch for them, and a great result for the pond and its visitors. Becky says “We were amazed by how quickly theses minute weevils controlled the problem, in a matter of weeks the pond was restored allowing wildlife to thrive “
The Countryside wardens at Stockton Council’s Billingham Beck Country Park also tried the weevil remedy. Warden Dave Neil says “One of our ponds was completely blanketed with a carpet of Azolla so that the pond creatures were being deprived of light and oxygen, I have to admit I was a bit sceptical that these tiny creatures would make any impact but after seven weeks I was staggered to see that the pond surface is completely clear.”
Click here to find out more about alien pond weeds, the problems they can cause and what you can do to stop their spread