Rona Charles – Senior Ecology Officer and Laura Winter – Aquatic Mammal Specialist and National Park Volunteer
There is often a gloomy tone to reports on Britain’s water vole (Arvicola amphibious) populations. For example, an Environment Agency spokesman has said that numbers in the UK are thought to have fallen by over 95% since the 1970s and a further 20% since 2011. But recent work by University of Aberdeen researchers shows that water voles can move from further from place to place than had been thought previously. This behaviour could give them a better chance to adapt to changing conditions, but only if there is still suitable habitat to act as corridors for them to travel through.
Despite difficult weather conditions over the last few years, and the presence of predatory mink, we believe that the North York Moors water voles are hanging on here in the uplands more successfully than in some other parts of the country. The best area here is in the east of the North York Moors, centred on Fylingdales Moor and Langdale Forest. The nature of this area means that the water voles are able to move and recolonize other sites when environmental and predation pressures render their usual habitats inhospitable. This is because
- there is a large number of tributaries, ditches and headwaters connecting two river systems in the area;
- there are large expanses of heather and forest providing cover for movement as well as pockets of water vole favoured habitat;
- and importantly, the major landowners in the area, are sympathetic to the needs of the animal and try to manage their land accordingly.
Water voles need lightly-grazed wetland habitat extending beyond the immediate banks of slow flowing becks and rivers. Legal mink control can give the water vole a better chance of survival, although good wetland habitats provide better cover for the voles to escape the attentions of all potential predators.
We’re definitely not complacent though.
The habitat connectivity programme we’re rolling out in the North York Moors will help to reconnect fragmented areas of valuable habitat and should give the water vole more chance to safely relocate and hopefully spread out. Peatland restoration on a number of moors over the last few years, plus the ‘Slowing the Flow’ project above Pickering, is resulting in water being held back for longer on the higher ground and the run off during heavy rain slowed. This is an advantage for water voles (slower-flowing watercourses and less flash flooding of their burrows), as well as hopefully for people living further downstream.