Why do water voles need your help?

Once a common sight along our waterways, water voles have rapidly disappeared from much of the landscape, experiencing the most serious decline of any British mammal over the last century.

Until last year, when 100 water voles were released by the National Trust at Malham Tarn, water voles were believed to have vanished from much of the Yorkshire Dales but it’s important to confirm whether this is the case with systematic surveys and also monitor to see if these reintroduced individuals successfully spread across the area.

The shocking drop in numbers nationally has been due to habitat loss and destruction along many of our waterways over the last century, as well as the release and spread of non-native American mink across the countryside since the 1920s. Water voles are particularly vulnerable to predation by mink as their usual tactics of diving underwater and kicking up a screen of dirt, or running into their burrow, sadly aren’t effective defences. The impact of mink has been particularly devastating; national surveys conducted between 1989-1998 found the water vole population crashed by nearly 90% during that period alone.

Immortalised as Ratty in The Wind in the Willows, water voles are a key part of our natural heritage. They have been in Britain since the last Ice Age and play an important ecological role along our waterways, as an indicator of a healthy environment, providing food for a range of native predators and even affecting the bankside plant diversity through the creation of their burrow networks. While they can be confused with rats, they are distinctly different. They are the largest of the British voles and are about the size of a guinea pig, with a round, chubby body, blunt nose and small ears hidden in thick fur. Usually they are dark brown, but black water voles can also be found - especially in Scotland.

Over the last couple of decades, conservation groups have been working hard to improve habitats and control mink numbers to try and save the much loved water vole, but it’s important to monitor how populations have responded and find out what the current national picture is, which is where the National Water Vole Monitoring Programme comes in…

The People’s Trust for Endangered Species (PTES) launched the first National Water Vole Monitoring Programme (NWVMP) across England, Scotland and Wales in 2015. The NWVMP aims to bring together all current monitoring, as well as resurvey sites from the previous national surveys, so we can find out what the current situation is and detect any future changes.

Following two successful years, this May PTES is once again asking existing volunteers and new recruits to survey sites for signs and sightings of water voles, to find out how populations are faring across the UK. As with many mammals, it is not always possible to see water voles even if they are present, so often the best way of confirming their presence is to keep an eye out for signs left behind. These include their droppings (usually left in piles called latrines), feeding signs/remains and burrows in the bankside (or in certain habitats, nests).

Last year over 400 sites were surveyed across the country and just over 40% had water voles present. The distribution of positive sites was skewed towards Scotland, partly due to a large number of sites being surveyed there last year, but encouragingly there were occupied sites across the UK from Cornwall to the Highlands. Sadly, last year PTES didn’t have any sites surveyed in the Yorkshire Dales area, but hopefully this year we can start to find out how they are faring.

Whilst this is overall good news, we still need more volunteers , so we can detect both national and regional trends in the water vole population in the future. New volunteers are being asked to register online and select a site to monitor annually. There are still available sites in the Yorkshire Dales to select, though if there aren’t any near where you live you can register your own site.

You will then need to survey one 500m length of bank at your site once during May, recording all signs of water voles, otters and mink. You don’t need to be an expert to take part in the NWVMP, though you will need to learn how to identify water vole field signs.

To find out more and sign up to take part, please visit www.ptes.org/watervoles