When it comes to choosing a home, we all have some fundamental questions to ask. Will my family be safe here? Will my home fall apart in bad weather? Do I have access to food and other essentials? Although water voles don’t have to consider things as complicated as mortgage rates and frequency of the local bus, the basic considerations are largely the same.  

The first important thing that we look at when considering whether a given area provides adequate habitat for a breeding water vole is the presence of water. While this isn’t an absolute necessity for their survival it is almost always present in occupied water vole habitat. This is because water plays a vital role in predator evasion. When any threat is detected, water voles will dive below the surface with a distinctive ‘plop’ and swim to the safety of their underwater or water-level burrows, where their natural predators are unable to follow. Water voles are not particularly strong swimmers, however, so the water in their habitat needs to either be still or run with a slow to medium flow. While their flowing water habitats (streams and ditches) are rarely more than two metres wide, they will happily occupy ponds and small lakes. This is probably more to do with the likelihood of flooding and fast water in a wider watercourse than the distance to swim between banks. 

Once we have established the presence of suitable water in an area, we will then look at the vegetation structure immediately surrounding that water, usually within 1-2m from the edge of the water. The vegetation on the bank serves two functions for them, cover from predators and food. Water voles are known to eat 227 different plant species so, while not picky eaters by any means, they need a good variety of palatable plants within their feeding zones. If there are trees on the water’s edge, they can shade out the ground resulting in homogenous and sparse vegetation at ground level. Invasive non-native plant species such as Himalayan balsam also cause problems for voles as they homogenise the banks over time, leading to ‘dead’ banks in the winter and spring when balsam recedes, and degrade the soil structure causing bank collapses.  

The best water vole habitat is open with few to no trees and scrub species like bracken which reduce sward height and diversity. High quality vegetation does not have to be continuous along a watercourse as water voles can leap-frog small stretches of unsuitable habitat within their territory as long as they can traverse the unsuitable sections safely. 

Water voles are burrowing creatures, and they rely on a sustainable burrow structure to survive winters and floods, rear their young and keep safe from predators. Typical burrow systems will have several entrances that sit underwater and at various heights on the bank as well as on top of the bank within the vegetation. This allows the voles to always be nearby an escape route regardless of the water height. However, if a watercourse doesn’t have much of a bank on either side or floods regularly above the bank height this could pose an issue for water voles, particularly when breeding. Similarly, if the bank is mostly made up of sand or stones it will be hard for voles to maintain a burrow. Ideal water vole habitat will have high and steep sided banks to the waters’ edge and the watercourse won’t flood above the bank height. They particularly favour undercut banks where the cover from aerial predators is even greater. 

These features are what we look at to determine ‘good quality’ water vole habitat. They are by no means a strict blueprint and water voles often surprise us with the areas in which they seem to thrive. They have been known to show up in habitat with wide and fast flowing watercourses or no water at all, areas with no burrowable banks to areas where they burrow between the stones of a retaining wall – they truly are not aware of the rules of the water vole handbook. What we do know however is the closer an environment is to the ‘optimal’ conditions, the more likely that water voles will be able to survive and thrive within it. 

Naturally Native is committed to improving ten kilometres of water vole habitat in the North East over the course of the project, working with partner organisations, local land managers and farmers, volunteers and young rangers groups to restore existing habitat as well as creating new features for water voles.  

These works will include 

• Restoring degraded and damaged habitat that could support water voles or improving existing water vole habitat that could do with some help in the future e.g. removing invasive plants like Himalayan balsam, removing scrub encroachment, fencing watercourses to stop stock grazing to the waters edge 

• Creating new habitat to connect populations, provide refuge during flooding or droughts, and encourage water voles to expand into nearby good quality habitat. 

• Educating landowners on how to accommodate for and improve things for water voles on their land. 

To find out more, get in touch with one of our Project Officers and watch for updates on our Facebook page https://www.facebook.com/NaturallyNative/