The water vole has been struggling to survive in Great Britain. They are currently considered one of the UK’s most endangered animals, with 94 percent of the local population disappearing in recent years. But there’s good news for this rodent: 150 of them are returning to the Holnicote Estate, a national park that lies along River Aller in Somerset.

According to The Guardian, a team of park rangers and volunteers will monitor the water voles to keep an eye on their numbers and behavior. This should be a relatively simple task, since water voles roam during the day.

Image: Wikicommons

The National Trust is releasing the first 150 water voles gradually into the estate this week, in either breeding pairs or groups of siblings. After the voles acclimate to the grounds, the National Trust will release another 150 in the spring.

The project is one piece of the National Trust’s £10 million riverlands restoration campaign, which was announced last month.

“Not only will it restore habitats for scores of wildlife, from the rare vendace fish in Derwent Water to otters and water voles, it aims to inspire people to value and care for our rivers. Motivating people to take responsibility and get involved will ensure this work is sustainable for years to come,” Hilary McGrady, director-general of the National Trust, said in a press release at the time.

The water voles are an especially welcome sight, since conservationists have been sounding alarm bells on their decline for several years now. This river-dwelling creature has faced severe habitat loss due to increased farming and urbanization since World War II.

But the American mink has also hunted local water voles relentlessly, adding a more recent wrinkle to their survival. As The Guardian explains, the mink problem began after the predator was released en masse from fur farms in the 1970s and 1980s.

The National Trust has high hopes for the water voles, which have received legal protection from the Wildlife and Countryside Act since 1981.

“I remember being enchanted by these creatures as a child,” Alex Raeder, the south-west conservation manager for The National Trust, told The Guardian.

Image: Flickr/Peter Trimming

“They were once a vital part of the Holnicote ecosystem and could be again. These voles should soon be busy burrowing into the muddy banks and creating more natural-looking edges to streams with shady pools that are great for so many other small creatures.”