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Water voles are to be given protection from persecution and accidental disturbance to try to stem the decline in their population.

The species, popularised as Ratty in Wind in the Willows, has suffered a fall in numbers of more than 90 per cent in less than 20 years.

Joan Ruddock, Minister for Biodiversity, announced today that the creatures are to be afforded the same legal protection as otters. From April 6 it will become an offence to kill or disturb water voles, and devlopers trying to build on their habitat will have to catch every specimen in the area and provide them with a new home.

Angel sharks, Roman snails, spiny seahorses, and short-snouted seahorses joined the water voles on the list of creatures to be given extra protection from under the Wildlife and Countryside Act 1981.

The two species of seahorse given protection from being caught or having their shelters disturbed have been used by the traditional medicine and aquarium industries. Numbers are thought to have slumped to the point where the species are at risk.

Roman snails, found mainly in central England, are a favourite among amateur cooks and the angel shark, which from April 6 has full protection up to six miles from the coast, is hunted by sports fishermen.

Mrs Ruddock announced the names of the animals while on a visit to the Wildfowl and Wetlands Trust's London Wetlands Centre in Barnes, southwest London, which has helped to provide habitat for the endangered mammals.

“It is in all our interests that England's valuable wildlife is protected, and a lot of work has been done to ensure that the list of species being protected is comprehensive,” she said. “The additional protection we are providing for these creatures will ensure a more secure future for their species."

The measures will apply initially only to England but officials from the Department for Environment Food and Rural Affairs are in negotiations with the devolved authorities for similar protection to be introduced in Scotland and Wales.

Habitat loss and predation by American mink are thought to have been the most serious threats posed to the water vole, but trapping and persecution are also thought to have played a role. Stephanie Hilborne, chief executive of The Wildlife Trusts, said “this life line” for the water vole was well overdue.

“Water voles have been lost from many parts of the UK, including significant areas such as Cornwall, but this excellent news will undoubtedly help our efforts to bring the water vole back from the brink,” she said.

“Full legal protection should ensure remaining water vole populations are not compromised during development works and that incidents of trapping and persecution do not go unpunished.”

Alastair Driver, of the Envivironment Agency, at which he oversees water vole conservation, described the measures as “great news” for the species. “It not only serves to minimise deliberate persecution and accidental poisoning, but also clarifies the law for planners and developers,” he said.

“Water vole populations have declined by 90 per cent since 1990 and this added protection will make a real difference to the work being done to conserve this charismatic species.”

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