A CONSERVATION group last night warned the well-loved water vole is facing extinction in Suffolk.Unless action is taken, Suffolk Wildlife Trust believes the creature will no longer inhabit the county's waterways.

By Sarah Chambers

A CONSERVATION group last night warned the well-loved water vole is facing extinction in Suffolk.

Unless action is taken, Suffolk Wildlife Trust believes the creature will no longer inhabit the county's waterways.

It is linking its devastating decline in two Suffolk rivers over the past six years to the introduction of American mink, which prey on the creatures.

Mink were originally brought to the UK in the 1920s and 30s, but by the mid 1950s were breeding in the wild following escapes from fur farms.

The Trust also believes habitat loss has taken its toll, but in places like the River Deben, habitat for water voles is still very good.

It plans to continue and expand a mink trapping programme on the rivers as it tries to halt the dramatic fall in numbers.

The Trust has just completed a study on the Deben and Alde Rivers funded by the Environment Agency.

It found that despite having plenty of suitable habitat for the creatures, the River Deben main channel has shown a 55% decline in water voles occupying sites. In 1997, nine out of 10 sites were occupied, but last year that fell to four.

The main channel of the River Alde has fared even worse – suffering a 100% decline. In 1997 there were four our of nine sites occupied, but last year there were none.

Since 1997, the Deben area overall has suffered a devastating 29% decline, while the Alde area witnessed a 75% drop.

SWT Water for Wildlife adviser Penny Hemphill, who organised the study, said there were other factors, but they alone did not account for the decline.

“What I found was that 90% of the main channel of the Deben was good habitat for the water vole,” she said.

There had been a loss of habitat or sedge cover along sections of the River Deben, and general habitat degradation, especially on the River Alde, she said.

“This is partly due to low water levels after the recent long hot summer, resulting in the drying up of many tributaries but these factors alone don't account for the decline.

“There is considerable evidence to suggest that mink might be responsible.

“The remaining water vole populations on the main channel of the River Deben have become isolated, making them increasingly vulnerable to predation,” she said.

The Trust predicted the fate of Suffolk's water vole in its 1997 survey, when numbers appeared much healthier, particularly on the Deben.

It warned that if mink numbers were to rise on the Deben and Alde, there was likely to be “an adverse effect” on existing water vole populations.

A mink trapping initiative started in 2001 by the Trust with the co-operation and support of local landowners shows that mink have become widespread on the two rivers, with more trapped in 2002/03 than in 2001/02.

Ms Hemphill said: “The Trust have initiated an action plan which involves improving water vole habitat, conducting more research, training and publicity.

“Targeted mink trapping initiatives will continue and expand and we shall be looking into using Game Conservancy Trust mink rafts on the Deben main channel,” she explained.

“We will also be offering mink trapping training days for staff of water companies, landowners, DEFRA and the Farming and Wildlife Advisory Group.”

The Trust's plan will also focus on encouraging landowners to manager freshwater habitats for water vole, and training volunteers interested in water vole survey work.

Anyone wanting more information should phone 01473 890089.

* Penny Hemphill is pictured by the River Deben at Kettleburgh, near Framlingham. In 1997, it was a breeding site for water vole, but they can no longer be found there.