back
to science
Action
for Water Voles
Water
voles
Tales from the river bank: "Ratty" under threat
Water voles, perhaps best known as the water 'rat' of Kenneth Grahame's book
'The Wind in the Willows', used to be common sight on our canals.
However,
water vole populations have declined dramatically in canals and rivers over
the last 50 years.
The decline of water voles is mostly due to a loss of suitable habitat and
predation by introduced mink, which had escaped from fur farms.
Water voles are now a protected species and many projects have been set up
to try and reverse the trend.
Water voles are still found in our canals, but many of the populations are
now small and isolated. Because they live at the water's edge, many maintenance
and recreational activities can affect them.
What do water voles look like?
A water vole
Water voles are the largest species of vole. Although they are often called 'water rats' they are not in fact rats at all, and differ from them in many ways. Water voles have much darker fur than rats, they have a blunter head with small body, a shorter tail, more rounded and less obvious ears and smaller eyes.
A rat
Where do water voles live?
Tall, lush vegetation along canal banks is essential for water voles to successfully
feed and breed. Water voles create residential burrows and bolt holes.
Drystone
canal walls and rip-rap sometimes support colonies, but hard vertical bank
protection systems cannot support viable populations. Water voles feed on
the tall grasses, sedges and rushes found on the river bank. Mink and water
voles The decline of water voles is closely linked to the introduction of
predatory American mink. Control of the now naturalised mink would help water
voles but is difficult because mink readily re-colonise - successful local
control is usually followed by new arrivals from neighbouring territories.
On a positive note, the return of otters to some areas of the country seems
to be linked to mink reduction and so the situation may improve as they return.
What can be done to help water voles on canals?
Careful planning of bank protection work is the best way we can help water
voles. Most vertical systems of bank protection, such as trench-sheeting,
are not 'vole-friendly', as they prevent burrowing and discourage bankside
protection. 'softer' methods of bank protection, using geotextiles or hard
methods that incorporate soft banks and vegetation, have been successfully
installed on many canals in recent years. These systems can help conserve
remaining populations and encourage the return of water voles to other lengths.
Telling water voles from rats is important, because we need to verify that
sightings of water voles really are voles - and educating people about the
differences between the two species is important.