New life for Dorset's rare winter streams

Dorset's famous winterbournes

Dorset’s rare winter streams are seeing new life, thanks to recent work by the Dorset Wild Rivers chalk stream project.  The special habitats of Dorset’s famous ‘Winterbournes’, which naturally flow only seasonally, are benefiting from restoration by the Dorset Wild Rivers project, led by Dorset Wildlife Trust with funding from the Environment Agency and Wessex Water.   

Dorset Wild Rivers is working to restore important chalk stream habitat across much of the county, including the Frome and Piddle Valleys and the chalk stream tributaries of the Stour, Allen, Tarrant and North Winterbornes.   The project is working with land owners, fishing groups and The Wild Trout Trust and has the backing of film-maker Simon King, who was filming on Dorset’s chalk streams during 2010.  
 

Home for rare mayfly

The aptly named winterbournes, which lend their name to many of Dorset’s villages, are temporary chalk streams, flowing only when the water stored in the chalk aquifer reaches surface level.  These special conditions provide habitat for wildlife including a rare water crowfoot and invertebrates, including the threatened mayfly Paraleptophlebia werneri and the rare blackfly.  Simulium latipes.  Both are expected to benefit from a 650metre section of new chalk stream habitat, created on the South Winterbourne at Winterborne Herringston, using skilled contractors under the close supervision of the Dorset Wild Rivers Co-ordinator.   Fish, including brown trout, are also expected to use the habitat for spawning in wet winters, following the flow downstream as the winterbourne dries out.

Sarah Williams, Dorset Wild Rivers Co-ordinator at Dorset Wildlife Trust, said: “These winterbournes are very special, appearing and disappearing quite naturally and providing a rare environment for wildlife.  With our partners we want to see them flourishing again in their secretive way as part of Dorset’s network of wild chalk rivers.  We have had previous success on the South Winterbourne at Winterborne Came, with both rare mayflies and blackflies recorded in the first season, so we have great hopes for Winterborne Heringston this spring.

Partners in the project include Wessex Water, Farming and Wildlife Advisory Group (FWAG), Dorset Biodiversity Partnership, Dorset Area of Outstanding Natural Beauty (AONB), Queen Mary University of London, Environment Agency, Natural England and Purbeck Heritage Committee.

For more information about the project, ring Sarah Williams on 01305 264620.