Bringing Back Surrey’s Voles
Registered Charity No. 208123
Conservation Status
Water voles
have been lost
from 94% of
their former
sites in Britain
Water Voles are an important part of our riparian biodiversity and are legally
protected in the UK, yet recent evidence suggests these creatures have suffered a
catastrophic decline in Britain, disappearing from 94% of their former sites.
Water voles were last recorded in Surrey in 2009.
Habitat loss and degradation
Water voles generally prefer water courses with wide luxuriant
stretches of bankside vegetation.
A combination of intensive agricultural practices, urbanisation and
river engineering has lead to a significant reduction in suitable
water vole habitat throughout the UK, including Surrey.
Predation from American mink
The introduced non-native American mink is widespread in the
UK and are a serious threat to water voles.
They are adept swimmers and their body shape allows them to
enter water vole burrows.
Nursing female mink can wipe out whole colonies.
Pollution
Poor water quality has a major effect on water voles.
Pollution sources may include point source pollution from pipes
and other fixed objects, run-off and poaching from fields, sewage
as well as algal blooms.
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Water Vole Identification
Identifying Features
Water Vole (Arvicola amphibius)
Star-shaped foot
Brown Rat (Rattus norvegicus)
Blunt nose
Long heel
Small hidden ears
Grey-brown fur
Large ears
Pointed nose
Large orange teeth
Shorter, furry tail
Long, scaly, pink,
hairless tail
Silky, mid-brown fur
At a Glance:
Size: 140-220mm with a 100mm tail
Weight: 140-350g
Fur: Thick, ranging from chestnut
brown to black.
Appearance: Rounded body with a blunt nose.
Short ears barely visible through it’s thick fur.
General character: Swims in doggy paddle.
Makes a loud ‘plop’ sound on entering water.
Not to be confused with…
Rats: Slightly larger with a longer nose, large
pink ears and a long, hairless tail.
Field voles: Similar head and body shape but
much smaller (90-115 mm) with a short tail and
greyish fur.
Bank Voles: Similar body shape and fur colour,
larger ears and longer tail (90-110mm).
Habitat: Found along waterways with wide
swathes of vegetation on either side, steep
banks and slow flowing, deep water (over 1m).
Sometimes seen around ponds, reedbeds and
other wetland habitats.
Diet: Feeds mainly on grasses and bankside
vegetation. 227 plant species have been
identified in their diet!
Life Expectancy: 5 months on average.
Maximum life expectancy in captivity is 2.
Reproduction: Usually 3 or 4 litters a year,
depending on the weather. Usually 5 in a litter
and weaned within 14 days.
Territoriality: Water Voles live in colonies
which are spread along the water course,
usually forming linear territories . Breeding
females are territorial (although they may
allow female offspring to share their territory),
whereas males have overlapping ranges.
Water vole, Elliott Neep; Brown rat, Gillian Day, Margaret Holland; Illustrations, Alex Learmont
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Know your Vole Signs
Learn how to find evidence of voles
1. The Tic Tac Test!
Water vole droppings are 8-12mm long and
4-5mm wide (very similar in shape and size to
a tic tac). They are blunt and symmetrical but
vary greatly in colour. Rat droppings are usually
larger and have an unpleasant odour.
Droppings are deposited in piles (known as
latrines) along water vole range boundaries,
near the nest and where they enter and leave
the water. A scent is secreted from glands
along the vole’s flanks and this is deposited
on the latrines by stomping its hind-feet. This
often leaves a flattened shelf of old droppings
topped with fresher ones.
2. Feeding Stations
Water voles often carry food items to favoured
feeding stations along runways where stems
are discarded in neat piles, usually up to 10cm
long. The stems are usually cut at a 45° angle
and may show the marks made by 2 incisors.
Feeding stations are also found adjacent to
burrow entrances. But beware the field and
bank vole! Both leave similar feeding stations
although the strands of vegetation tend to be
much smaller.
3. Burrows, lawns and runways
Burrows are found in steep bank sides, usually
wider than they are high, with a diameter
between 4-8cm. These will appear at varying
levels in the bank, with some at the waters
edge or even completely submerged. These
waterside burrows may appear larger due to
erosion but will always contract down to the
size of 2 fingers. Kingfishers and Sand martins
nest in holes higher up in the bank, other voles
and mice make much smaller burrows (2-3cm)
whereas rat holes are much larger (8-10cm)
and may have a fan-shaped spoil heaps outside
the entrances.
Water vole burrows will sometimes have a
small ‘lawn’ outside where breeding females
have been grazing the near by vegetation in
order to minimize the amount of time spent
away from her young.
Water voles will utilize the same routes from
the waters edge, through bankside vegetation
to the burrow. This creates clear pathways
through the vegetation which is often
surprisingly visible. They are usually 5-9cm in
width.
Footprints
These are only found in soft substrates,
usually in mud or sand along the margin on
the water course. Water voles are said to
have ‘star-shaped’ feet but are very similar
to juvenile rat prints. One distinguishing
feature is the brown rat has longer heels on
the back foot than water voles and leave a
deeper imprint. As rats are nocturnal they
also spend more time in the open under
the cover of darkness whereas water voles
tend to stick to the waters edge or use
vegetation as cover during the day.
Water vole foot
Rat foot
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Otter or Notter?
Learn how to identify a mink from an otter
Mink At a Glance:
Size: 56cm with a 29cm tail
Weight: Adult males, 5kg, adult females 4kg
Fur: Dark brown, looking black when wet. Small white patch on chin, sometimes on throat
and chest as well.
Appearance: Very sleek animal, long, thin with a short, fluffy tail. Pointed muzzle. Similar size
to a ferret.
General character: Fast swimmers, carrying their heads high above the water.
Habitat: Mink are amphibious and are typically found along rivers, in wetlands and coastal
areas. Fairly common across Surrey’s waterways.
Diet: Mink have a varied diet including small mammals, fish, birds and will occasionally take
crayfish and other invertebrates.
Life Expectancy: 10-12 years in the wild.
Reproduction: Females have one litter of 4-6 kittens a year in May. They reach adult size by
the autumn and can breed at one year old.
Otter At a Glance:
Size: 60-80cm with a 32-56cm tail.
Weight: Adult males 8.2kg, females 6kg
Fur: Brown fur, often pale on underside.
Appearance: Long yet muscular body with a long thick tail and webbed feet. Broad, dog-like
muzzle with a wide head.
General character: Powerful swimmers low in the water with only head and tail visible.
Habitat: Otters are amphibious and so are found along rivers, in wetlands and coastal areas.
Although still extremely rare in Surrey, otters have been recorded on both the river Wey and
Mole.
Diet: Mainly fish but will also take crayfish, frogs and occasionally water birds such as coots.
Life Expectancy: Can live up to 10 but rarely survive more than 5 years in the wild.
Reproduction: Usually two or three otter cubs are born in a litter and this can be at any time
of the year. Cubs stay underground in holts until they are 10 weeks old.
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