(Myotis daubentonii)
Daubenton’s bat is a medium-sized British bat often seen flying just above the surface of ponds, lakes and rivers. Known as the water bat, it has a remarkable way of hunting, using its large feet and tail membrane to catch insects from the water. Look for its low, steady flight on a calm evening and you may discover one of the most fascinating sights in your local wildlife.
Meet the water bat
As dusk settles beside a river, the water can appear almost empty. Then a small shape begins to skim across its surface, turning and sweeping back and forth, sometimes passing so close that its reflection seems to follow beneath it.
This is the Daubenton’s bat, a species particularly well adapted to hunting over water. Unlike bats that weave through trees or chase insects high above a garden, it often keeps to a remarkably low flight, picking small insects from the surface as it goes.
You don't need specialist equipment to enjoy watching one. A pond, lake, canal or slow-moving river can provide a good place to look, especially on a calm evening. Identifying the species from its flight and hunting behaviour is often easier than identifying it from its appearance alone.
How to identify a Daubenton’s bat
Daubenton’s bat is medium-sized, with a relatively pale underside, reddish-brown fur on its back and a pinkish face. Its large feet are an important adaptation for catching prey close to the water.
At a glance:
- Head and body length: 4.5–5.5cm
- Wingspan: 24–27.5cm
- Weight: 7–12g
- Fur: Red-brown above, paler underneath
- Face: Pinkish, with relatively bare skin around the eyes
- Most useful field clue: A steady, low flight just above open water
These measurements are useful for comparison, but a bat flying past in poor light is unlikely to offer a clear view of its size or colouring.
How is it different from other bats?
Daubenton’s bat is most readily recognised by its hunting behaviour. It commonly flies in repeated passes over water, often only a few centimetres above the surface, while other species may hunt higher over the banks or among nearby trees.
Other bats also feed over water, so this behaviour is a strong clue rather than a guarantee. Its large feet can be difficult to see without a close view, and reliable identification may require a good observation or help from someone experienced with bats.
A bat detector can add another clue. Daubenton’s bat produces echolocation calls across a broad range of frequencies, with the strongest energy typically around 45–50 kHz. Its calls can sound like rapid, regular bursts of clicks on a detector. However, calls overlap with those of other species, so a detector reading alone does not always provide a definitive identification.
Where do Daubenton’s bats live?
Daubenton’s bats are widespread across much of Great Britain and Ireland, although they are scarce in some northern and mountainous areas. They are particularly associated with freshwater habitats, including lakes, ponds, canals and rivers.
Water is central to their feeding habits, but they also need safe places to roost during the day. In England and Wales, known summer colonies are often found in underground or sheltered structures close to water, such as bridges, tunnels, caves, mines and cellars. Old stone buildings can also be used, while tree holes are likely to be more important than records alone suggest.
Roosting habits vary around the UK. In Scotland, colonies are more frequently recorded in buildings. Daubenton’s bats have also been found using bat boxes, sometimes alongside other bat species.
Individuals may use several roosts through the year, and a bat seen feeding over a pond does not necessarily roost in the nearest tree or building. They can travel several kilometres between a roost and feeding grounds, and some have been recorded following canals for much longer distances.
When do Daubenton’s bats emerge?
Daubenton’s bats are active after dark, with the warmer months offering the best chance of watching them hunt. Visit a suitable stretch of water around dusk and look for a small bat making repeated, low passes across the surface.
Their flight is often steady and purposeful, with quick turns as they follow concentrations of insects. If you watch for a little while, you may notice the same stretch of water being crossed repeatedly.
Calm conditions can make their hunting behaviour easier to observe. Avoid shining bright lights directly over the water, as artificial lighting can disrupt bats and their movement through the landscape.
What do Daubenton’s bats eat?
Daubenton’s bats feed mainly on small insects associated with freshwater habitats. Midges are important prey, alongside caddisflies, mayflies and other small flies.
Their hunting technique is what makes them so distinctive. Flying low over the water, they can catch insects in their mouths or use their large feet and tail membrane to scoop prey from the surface. Larger insects may be carried to a perch to be eaten.
This close relationship with water means that a healthy pond, lake or river can provide both a feeding ground and part of a wider route through the landscape. The insect life around the water matters, too: pollution, changes to aquatic habitats and the loss of waterside vegetation can affect the supply of prey.
How do Daubenton’s bats breed?
Daubenton’s bats mate in autumn, and males may continue to seek out females during winter. From late spring, females gather in maternity roosts to give birth and raise their young.
Colonies commonly contain around 20–50 bats, although larger groups have been recorded. Young bats are suckled for several weeks and become independent at around six to eight weeks of age.
Maternity roosts can remain occupied through the summer and sometimes into October. Males and females that are not breeding may use separate communal roosts, although they can sometimes join maternity colonies.
Roost sites are particularly important during this period. Disturbing a colony can put adult bats and their young at risk, so any suspected roost in a building, bridge or tree should be left alone.
Where do Daubenton’s bats go in winter?
As temperatures fall and flying insects become scarce, Daubenton’s bats become less active and spend the winter hibernating.
They often choose underground places such as caves, mines and tunnels, where conditions are sheltered and relatively stable. Bats may squeeze into narrow cracks and crevices, sometimes leaving very little of their bodies visible.
Some individuals arrive at hibernation sites in autumn, while numbers at particular underground sites can increase later in winter. They may use different locations at different times of year, so the place where you watch a bat feeding in summer may be quite separate from its winter refuge.
Hibernating bats must be left undisturbed. Waking from torpor uses valuable energy reserves, and underground sites can be especially sensitive to disturbance.
Daubenton’s bat population and conservation in the UK
Daubenton’s bat is classified as Least Concern in Great Britain. The UK population is estimated around 1 million, although counting bat populations is difficult.
The species has adapted to a landscape shaped by people. Britain's historic canal network, with its bridges and sheltered waterways, has provided both feeding habitat and potential roost sites. Artificial water bodies, including reservoirs and flooded quarries, can also provide useful habitat.
That does not mean water habitats are secure. A decline in aquatic insects, pollution, the removal of waterside trees and vegetation, and disturbance or loss of roosts can all affect bats. Protecting connected waterways and their surrounding habitats helps maintain both food supplies and safe routes between roosts and feeding grounds.
How can you help Daubenton’s bats?
You can support this species by looking after the places it relies on, rather than trying to attract it with food.
- Protect ponds and waterways. Keep freshwater habitats clean and avoid introducing pollutants, pesticides or garden chemicals into drains and watercourses.
- Retain waterside trees and vegetation. Mature trees, hedges and natural banks provide shelter, insect habitat and routes for bats to navigate.
- Reduce unnecessary lighting. Keep lights away from ponds, tree lines and likely bat routes wherever possible.
- Protect potential roosts. Do not block gaps in bridges or buildings, fell a tree with a suspected roost, or carry out work that could disturb bats without first obtaining appropriate professional advice.
- Watch quietly at dusk. Choose a suitable waterway, stand back from the bank and give bats space to hunt undisturbed.
Would a bat box help?
Daubenton’s bats have been recorded using bat boxes such as the Schwegler 2F DFP and the Schwegler 1FD, but a box is not a substitute for a suitable natural roost or a guarantee that bats will move in. If you have a suitable location, choose a well-made, untreated box and position it high up, sheltered from strong winds, away from artificial lighting and close to trees or hedgerows that bats can follow.
Several boxes facing different directions can offer a range of temperatures. Being close to water may be useful where the species is already present, but the surrounding habitat and availability of suitable roosts matter too. It can take months or years for bats to discover a new box.
Daubenton’s bat FAQs
Where is the best place to see a Daubenton’s bat?
Look beside a pond, lake, canal or slow-moving river at dusk during the warmer months. Watch for bats flying repeatedly just above the water’s surface.
Can Daubenton’s bats live in gardens?
Yes, if a garden is close to suitable water and forms part of the wider landscape they use. A garden pond may attract insects, but seeing a bat over the water does not prove that it is a Daubenton’s bat.
Do Daubenton’s bats really catch insects with their feet?
Yes. Their large feet and tail membrane help them take insects from the water’s surface, although they also catch prey directly in their mouths.
Do Daubenton’s bats use bat boxes?
They have been recorded using bat boxes, but occupation depends on the location, design and availability of other roosts. A box should never be opened to check whether bats are inside.
Are Daubenton’s bats protected?
Yes. All UK bat species and their roosts are legally protected. Do not handle bats or disturb a suspected roost. If you find an injured bat or need advice about a possible roost, contact the Bat Conservation Trust or a local bat group.
