One of the UK's most endangered species could soon be making a comeback in a corner of Cheshire.
More water voles could be released in 2008
Water Voles, although once common, are declining in numbers and figures suggest they could eventually disappear from 94% of their former sites.
Staff at Chester Zoo are releasing 48 voles - bred as part of a conservation programme - into the grounds.
All of the mammals have been fitted with tiny 4g radio collars to track their dispersal and survival.
The water vole is thought to have been driven to the brink of extinction in some areas as a result of being preyed on by the American mink.
Mike Jordan, curator of higher vertebrates, said: "By releasing these voles within zoo grounds, we will essentially be providing a safe haven for them from the American mink.
"We hope to establish a key population safe from mink predation, and monitor them to check their survival.
"It will be particularly interesting to see how the voles colonise the zoo site."
It is the first reintroduction of water voles at the zoo and more are expected to be released into the grounds in 2008.