Watervoles are becoming scarce on Isle of Wight river banks.
"RATTY" is becoming scarcer on Isle of Wight river banks — its most important stronghold in the country.
Surveys have shown the water vole — "Ratty" in The Wind in the Willows — to be in decline on the Island.
Conservationists have pinned the blame of the decline of a nationally significant Island population on the invasive Himalayan balsam, which is crowding out native water vole food-plants.
Last summer, the Hampshire and Isle of Wight Wildlife Trust carried out water vole surveys on the Western Yar, Eastern Yar and Gunville Stream.
The trust said, worryingly, these and previous surveys carried out in 2003 and 2008, showed declining numbers.
Conservationists recognise the water vole as one of the Island’s most important wetland species. The Island is seen as a sanctuary, because there is no American mink population. The predatory mink has contributed to the water vole becoming the fastest declining mammal in Britain.
The Himalayan balsam is a non-native invasive wetland plant, which grows in tall, dense, patches, where it prevents the native food plants of the water vole from growing.
In partnership with Bournemouth University and the Environment Agency, the wildlife trust has found numbers of water vole decrease where Himalayan balsam plants have spread to cover more than ten metres of river bank.
In partnership with the Non-native Species Local Action Group, work began last year to pull up Himalayan balsam at sites along the Eastern Yar.
More work is planned for spring and summer, where volunteers can help to improve habitat for water voles at Sandown Meadows Nature Reserve, which has recently been acquired by the Wildlife Trust, thanks to a generous legacy donation.
• Volunteers can contact Nicola Wheeler at the Wildlife Trust on firstname.lastname@example.org or by calling 01983 760016.