Water vole reintroduction in the Lake District

To the Lake District now, and hundreds of water voles have been released at a secret location close to Haweswater. The move is part of an attempt to create a thriving population of the endangered species in Cumbria. Chris spoke with Lee Schofield, site manager for RSPB at Haweswater...

李-水鼠以前abundant and very widespread species. Sadly, due to predation by invasive American mink, and also habitat loss, they've declined by something like 90%. We've been working really hard around Haweswater to restore the habitats, to restore a whole kind of mosaic of habitats actually, and also to control those mink in order to bring the water voles back again. And we know that they were there quite recently, there were old burrows there suggesting that they were probably around in the area a few decades ago - 40, 50 years ago. And they were a really important species in their own right, of course, but they're also a really vital part of the whole ecosystem. They're a big prey item, so they feed lots and lots of other species. So it is really important to bring them back for their own sake, but also for the health of the whole ecosystem.

Chris - Where do you get them from in the first place when you want to do a reintroduction programme like that? Do you breed them up artificially as it were, and then transport them? Or do you go to an area where they're in relative abundance and trap some and bring them? What's involved in moving and then reestablishing a species like this?

Lee - So these ones came from a specialist conservation breeder, a chap called Derek Gow, and he has built up locally specific, captive bred populations. So because we're in the North of England, these are a sort of Northern clade. So they were taken from a site that, as you say, had sufficiently healthy populations from which some could be taken. They've been bred up to build up the numbers and their numbers can be built up very quickly. Like all rodents, they reproduce very rapidly. So each female water vole can have between two and five litters a year, and each of those litters can have between two and eight young per litter. So when the conditions are right, their populations can build up very rapidly. So Derek Gow provided these animals to us and we released 204 of them into the site that we're looking after up at Haweswater, and then a further 161 were released just down the valley.

Chris - And what is the marker of success? How would you know if they're actually establishing and doing well?

Lee - So we can survey for them. They leave quite distinctive signs. They're quite secretive creatures. A good quality habitat for water voles is very complex with lots of places for the animals to hide away in. But they do leave very conspicuous droppings. They have droppings, which are described as being about tic-tac sized and shaped, so they're relatively easy to find and they also leave tracks and slides and tunnels, quite distinctive burrows that have one opening on the surface and one near the water's edge. We'll be able to confirm that they're still present and what we want is for their population to expand. So the two populations, they're on the same catchment. So over the course of the next few years, we're going to be working with Eden Rivers Trust and a range of other partners to try and fill in that gap, so we hope that they will expand naturally as we continue to control the predatory mink. But also we can supplement with additional releases to get a connected landscape scale population reestablished again.