Leaky dams help restore wildlife to dried-out Dorset bogs

Leaky dams may not sound ideal but they are being used to great effect on dried-out marshland in the West Country to produce fresh habitats for carnivorous plants and a spider that whizzes over the surface of water to grab prey.

- Steven Morris

Bales made of heather, and bunds constructed out of peaty soil and timber, are being used to create porous dams on two mires, Agglestone and Greenlands, in Purbeck, Dorset.

The idea is that the dams block ditches originally dug to drain marshes for conifer plantations or for farmstock grazing and encourage water to seep away slowly and "rewet" the dried-out mires.

David Brown, the lead ecologist in Purbeck for the National Trust, which manages the mires, said this project would bring about a richer landscape for flora and fauna and create fresh peat, an excellent carbon store.