Wednesday, 8 August 2012

River Avon gets source to sea protection to wipe out alien plant species

A new three-county project will stem the spread of non-native invasive plants throughout the River Avon and its tributaries to protect the future of their native wildlife. According to those involved, nothing on this scale has been tried before in the UK.

Wiltshire Wildlife Trust has joined forces with Hampshire and Isle of Wight Wildlife Trust and Dorset Wildlife Trust to get rid of plants such as Himalayan balsam, Japanese knotweed and giant hogweed among others that threaten to overwhelm native wildlife in the waters and on the banks of this internationally important river catchment.

Called Source to Sea, the project has received substantial backing from the Environment Agency. The river rises in the Vale of Pewsey in Wiltshire and passes through Hampshire at the edge of the New Forest before flowing into the sea at Christchurch in Dorset, which is why an integrated approach across county boundaries is so crucial to its success.

Sam Stork, Source to Sea project manager at Wiltshire Wildlife Trust says: “The Salisbury Avon and tributaries such as the Nadder and Wylye are magical waterways recognised for their magnificent wildlife by being designated as Sites of Special Scientific Interest and Special Area of Conservation.

“Non-native invasive plants could threaten the survival of their water voles and otters, Atlantic salmon, brown trout and lamprey if we stand by and do nothing while these plants steadily suffocate the banks.

“For the project to succeed we will need lots of volunteers to help us pull up the balsam, and we will need the help and support of riverside landowners to either remove the plants or allow access for our volunteers to remove them,” says Sam.

Joanne Gore, Field Officer for the Hampshire and Isle of Wight Wildlife Trust says: “I am very happy to be working with my colleagues in Wiltshire and Dorset to tackle non native plants on this internationally important river catchment. Tackling the problem from source to sea will ensure that the project can look to effectively control the devastation caused by non native species. Nothing on this scale has been tried before.”

Joanne has already begun working in the Hampshire Avon valley, supporting landowners who have non-native plants on their land. “I have been delighted by the response of landowners on the river catchment. They have been very willing for me to survey their sections of the river catchment and have allowed me to organise contractors and volunteers to help remove non native plants, like balsam, where they have been found.”

Amanda Broom Conservation Officer at Dorset Wildlife Trust says: “Invasive alien plants are threatening our streams, rivers and their wildlife. We have been working to remove this threat in Dorset and we welcome this opportunity to take the fight to the very east of the county and one of its most iconic rivers.” Himalayan balsam is an annual plant that grows into bankside thickets, crowding out all native wildlife. Then when the stalks die back in winter it leaves bare river banks that are vulnerable to soil erosion.

The key to its control is to pull the plants up while it is flowering and before it releases it seeds, because if these get into a water system they very quickly spread and can colonise areas downstream. Japanese knotweed and giant hogweed cannot be tackled by the public – only by someone who has gained a certificate in herbicide application.

The Source to Sea Project builds on existing work to control invasive non-native plant species funded by Defra, Environment Agency and Natural England. The Project has full support from Natural England and Richard Cresswell, the Environment Agencies regional director for the South West. Previous work has targeted hotspots of non-native plants on the Avon and other rivers, but never has a whole catchment programme been attempted before.

If you are a land owner on the River Avon catchment and would like further advice on non-native invasive plants or would like to volunteer for the project to help carry out surveys or practical work this summer then please contact:
Sam Stork on (01380) 736066, email:
for Wiltshire.

Joanne Gore on (02380) 424205, email
for Hampshire and Dorset.