Water Voles – an endangered species

The June meeting of the Alston Moor Historical Society welcomed Ruth Dalton and John Webster of the Cumbrian Water Vole Project who gave a joint presentation entitled ‘Water Voles – an endangered species’. Ruth is the water vole project officer for Cumbria and John has had many years experience of the subject as a member of the Mammal Group. Most people associate the water vole with Ratty of Wind in the Willows fame. Unfortunately this has also resulted in many people referring to the vole as a water rat – which it is not. It is a docile, endearing and timid creature which causes no offence to anyone, unlike the rat.

There has been an upsurge of interest in the creature in recent years after there was a realisation that there had been a serious decline in numbers since the early 1980’s with a crash of some 88% in the seven years between 1989 and 1996. It is estimated that throughout the North West, 96% of the population was lost.

The situation in Cumbria is that there is evidence of a significant presence until 1980, at which time the decline commenced and in a survey throughout Cumbria in the 1990’s no evidence of the vole was found. Subsequently it was ‘discovered’ on Alston Moor and has a good foothold in this area. The Society was particularly interested to learn more of what is happening in it’s own catchment area as the situation is both remarkable and unique. Ruth gave background details of the voles diet and preferred living environment, including clues to identify their presence. They are normally to be found within 2/3 metre of a watercourse and the abundance of gills and streams in the area suits them very well. The mortality rate is high and not many reach maturity although this is balanced to a certain extent by the fact that a female can breed up to 5 times per annum.

It is difficult to categorically specify the reason that they prosper on Alston Moor, particularly in view the generally harsh climate that is a feature of the area. Similarly, the factors contributing to the decline elsewhere cannot be definitively identified. A combination of the erosion of river banks by cattle, water extraction from waterways and pollution has played a part. However the vole’s major enemy is the North American mink. These creatures were farmed for their pelts but some escaped into the wild and even more were illegally released by animal activists. Presumably these people did not realise the devastation their action would cause to the indigenous population of small mammals. Following its release in 1956 the mink spread rapidly throughout the UK. The vole had hitherto been able to escape from predators in the water by going on to land, and on land by going underground. Unfortunately the mink is a strong swimmer and can also get down the holes on land, unlike other land based predators, so that the vole has no defence against them.

John Webster displayed a map of Alston Moor and highlighted the many confirmed sites of vole presence. An appeal to landowners in the area produced a very encouraging 50 invitations to carry out detailed surveys.

Why the water vole has survived in Alston Moor is not due to any one particular reason. The problems which operate elsewhere are perhaps not so pronounced with less cattle farming, lots of waterways, less pollution and, most importantly, it could be that the presence of valuable shooting moors produces more effective pest control of the mink which is a threat to young birds. The Society is delighted that the Moor supports this endangered species and invites anyone throughout Cumbria, and particularly in the Alston area, who thinks that they may have water voles on their land, to contact the Trust on 01539 816300. They will be very interested in carrying out a survey and would be very happy to find evidence of the water vole elsewhere in Cumbria.

The next event on the Society’s calendar is the outing to Alnwick Castle on the 9 th July. This is open to non-members and anyone interested should contact Alistair Robertson on 01434 381769