UK Bats: Species, Habitats, and Conservation

Bats are the world’s only mammals capable of true flight, and they represent nearly a quarter of all native mammal species in the UK. These nocturnal animals are a varied group, playing a part in the ecosystem that often goes unnoticed. Understanding the lives of these creatures offers a glimpse into the health of our shared environment, from remote woodlands to bustling urban gardens.

Discovering UK Bat Species

The UK has 17 resident bat species that vary in size and appearance. Among the most frequently seen is the common pipistrelle, a tiny bat weighing about the same as a twenty-pence piece with a wingspan of around 22cm. Its erratic flight pattern shortly after sunset makes it one of the more recognizable bats, accounting for a majority of UK sightings.

Another common species is the brown long-eared bat, distinguished by ears nearly the length of its body. This medium-sized bat has a slow, fluttering flight and forages close to vegetation. Near water, Daubenton’s bat is a common sight, skimming low over rivers and lakes to catch insects from the surface. The noctule is one of the UK’s largest bats, with a wingspan up to 36cm, and often flies high in the open before sunset.

Where UK Bats Make Their Homes

Bats across the UK inhabit various environments, from natural woodlands to man-made structures. Woodlands are a primary habitat, as most British bat species evolved to live in trees. Mature trees with cavities, woodpecker holes, and loose bark provide roosts for species like the noctule and Bechstein’s bat. Hedgerows and waterways act as corridors, allowing bats to travel between roosts and feeding grounds.

Bats require different roosts throughout the year. In summer, female bats use warm, sheltered maternity roosts like tree hollows or building roof voids to give birth and raise their pup. For winter hibernation, they seek locations with cool, stable temperatures and high humidity, such as caves or mines. Many species have also adapted to using buildings, finding shelter in crevices behind tiles, in cavity walls, or under barge boards.

The Nightly Feast: What UK Bats Eat

All UK bat species are insectivores, helping manage local insect populations. A single common pipistrelle can eat up to 3,000 small insects in one evening. They prey on nocturnal invertebrates like midges, moths, and beetles. Different species have their own preferred prey and hunting styles; for example, the brown long-eared bat often picks moths and spiders directly from foliage.

To navigate and hunt in darkness, bats use echolocation. They emit high-frequency calls and interpret the returning echoes to build a “sound map” of their surroundings, allowing them to detect an insect’s size, shape, and movement. While their eyesight is good, their hearing is what allows them to pursue and capture prey with remarkable precision at night.

Protecting UK Bats and Ways to Help

UK bat populations face several threats from human activity. A primary threat is the loss of habitat, including roosting sites in old trees and buildings and foraging areas like hedgerows. A decline in insect numbers, driven by pesticide use and agriculture, directly impacts their food supply. Other risks include roost disturbance, attacks from domestic cats, and light pollution that disrupts their feeding and commuting habits.

All UK bat species and their roosts are legally protected. It is a criminal offense to deliberately capture, injure, or kill a bat, or to damage or destroy its roost. Therefore, homeowners and developers must check for bats before undertaking any work that could affect them. If you find a grounded or injured bat, contact the Bat Conservation Trust or a local bat group for assistance.

Individuals can contribute to bat conservation in several ways:

• Plant a bat-friendly garden with night-scented flowers like evening primrose or honeysuckle to attract moths and other insects.
• Reduce or eliminate the use of pesticides to help maintain a healthy insect population.
• Install a bat box to provide an alternative roosting site.
• Build a small pond to create a habitat for insects with aquatic larvae, which provides a food source for species like Daubenton’s bat.