Water voles hold an unenviable record: they are thought to be Britain’s fastest declining mammal.

Hunted and devoured by the voracious American mink, which were introduced for the fur farming industry, they have also got loss of habitat, pollution of their waterways and population fragmentation to worry about, all of which have had a devastating effect on their numbers.

Listed as a priority species in the UK Biodiversity Action Plan , a recent estimate suggests a population drop from 7 million to 1 million. It is predicted water voles may eventually disappear from 94 per cent of their former sites.

But it’s not all bad news. Concerted efforts to reverse the water voles’ long-term decline are occurring across the country. In April this year, 64 water voles were released at a secret location near Bristol. The voles were captive-bred at Bristol Zoo Gardens and Wildwood Discovery Park in Kent. Fifteen of the rodents were radio-collared, enabling scientists to monitor their welfare. The colony has settled in well, and the voles have set up their territories as expected. The first wild-born offspring have already been seen.

As well as the Essex Mammal Group , whose work is featured in this month's video, four other LHI projects are also working to conserve the vole. 'Friends of Riverway' are surveying a site that is the only remaining breeding area for water voles in Stafford. They will also be producing a management plan. The Hurst Water Meadow Trust has worked to improve the habitat of water voles in meadowland in Oxfordshire. The Holy Brook Heritage Project aims to increase awareness of a waterway in Reading that is a habitat to water voles and otters and the Researching Ratty project in Northumberland are raising awareness of both the water vole and the water shrew.

Water voles are the largest of the British voles and range across Europe and east to Siberia and Mongolia. They are widespread across Britain, but are less common on higher ground and are absent from most of north Scotland and all of Ireland. They tend to inhabit the banks of ditches, slow-moving rivers and streams. Next time you are in such a habitat, look out for the signs that give away the presence of water voles: cylindrical droppings, often piled up in latrines; chewed lengths of grass and other plant material, often left at specific feeding areas; and burrow holes both above and below the water line, often with grazed areas surrounding the entrance. Water voles also leave characteristic tracks in the mud. The forefoot has four toes, which leave a star-shaped pattern, while the hind foot has five toes.

Unfortunately for the harmless water vole, people sometimes mistake them for brown rats, and persecute them as a pest species. Voles have smaller ears, blunter noses, shorter and furrier tails, and a more rounded shape. Even more confusingly, they are sometimes called water rats, and the famous ‘Ratty’ in Kenneth Grahame’s The Wind in the Willows was actually a water vole!

The animals themselves are not currently protected, although it is illegal to damage their place of shelter. The Joint Nature Conservation Committee (the Government’s wildlife advisor) has recommended that their status be upgraded, so it would also be illegal to intentionally kill, injure or remove water voles.

The combination of habitat restoration, reintroduction and protection should help to restore numbers of these charming mammals, and make them a more familiar sight along British waterways.