Water Voles are, unfortunately, one of the most endangered species of British mammals and have special protection under the Wildlife & Countryside Act 1981, with the protection extended in April 2008. Here at St Nicks, therefore, we have a serious responsibility to try to protect the few Water Voles which frequent the two becks running through the reserve.
In 2012, nearly all the Water Vole sightings at St Nicks were in Tang Hall Beck, being recorded on 12 visits. However, after the two Autumn floods, which covered their two-level burrows, sightings declined. But in the past two months, they have been seen on several occasions, mainly in Tang Hall Beck, near the Sluice Bridge, on the Northern edge of the reserve, but with one or two sightings on Osbaldwick Beck.
How are we helping Water Voles at St Nicks? Water Voles are very dependent on healthy vegetation growing next to waterways. They are exclusively herbivores, eating a wide range of plants (more than 200 species of plants have been recorded as food items in the UK alone). They also need stable beck-side banks, because they burrow into the banks, with burrows at two levels to accommodate different water levels. The main threat to their habitat at St Nicks is the alien and intrusive plant, Himalayan Balsam, which can take over stream banks, destroy native vegetation and cause erosion of the stream banks. So, once a year, a team of St Nicks volunteers try to clear as much of this plant species as possible from the banks of the two becks, Tang Hall Beck in particular.
How to recognise this species: Most sightings at St Nicks are of Water Voles swimming across the becks, although they have also been seen feeding on beckside vegetation.
The main species with which it can be confused is Brown Rat, which is also present at St
Nicks, and can also be seen swimming. The key features to look for are (1) the nose: Water Voles have a “kinder” looking blunt nose compared with the Brown Rat’s pointed nose; (2) the tail: Brown Rat has a pink, bare-looking tail whilst the Water Vole has a brown tail; and (3) the ears: Brown Rat’s ears are pink and exposed. The Water Vole has short, furry ears, almost hidden by its long fur. The Water Vole is the UK’s largest vole, growing up to 25 cm, with another 15 cm of tail – about the same size as Brown Rat.
North Yorkshire: Populations have declined from whole catchments in North Yorkshire, possibly due to predation (from Mink), habitat loss and water pollution. Hopefully, the cleaning up of North Yorkshire’s rivers (which has resulted in a boost to Otter populations), will help the recovery of Water Voles.
St Nicks: Possibly bred in 2012. A sighting of two Water Voles, with one being smaller (suggesting a juvenile), leads us to believe that they might have bred on the reserve. Recent sightings could be wandering voles looking for a mate (they can travel several kilometres to do this), or it might be a sign that they are returning after last autumn’s floods. The Wildwatch team have seen a number of new beck-side holes which might be Water Vole burrows.
Trivia: “Ratty”, in “Wind in the Willows”, was a Water Vole, not a rat! Water Voles are often called “water rats”, but are only distantly related to rats.