There are 101 mammal species in the UK, 12 of which have been added to the UK ‘red list’. One in five of British mammals are at risk of extinction, due to factors such as climate change, destruction of wild habitat, spread of disease and the use of pesticides.


Birds are a class of vertebrate animals (class Mammalia). Shared features include mammary glands in females, fur or hair and three middle ear bones. Worldwide the largest orders are the rodents, the bats and the shrews. Other large groups include the primates, the cetaceans and the carnivores.

  • Two dolphins swimming

Mammal Identification

Great Britain and Ireland have a relatively small number of mammals, with around 55 native and naturalised land mammals (including16 bats) and around 25 cetaceans and seals. Other free-living but introduced mammals may be seen, including feral goats, cats and ponies.

It’s generally easy to decide which order the mammal belongs to, but identifying to species level is more difficult. Easily confusable groups include the mice, voles and shrews, the deer and of course the bats.

Many mammals are shy or nocturnal, which makes them difficult to see. However mammals often leave signs to show that they have live in or have visited an area. Field evidence includes tracks, droppings, burrows, nests and feeding signs. With practice it is possible to identify the species from these signs.

(a) Tracks: Footprints and tracks are very useful for recording a broad range of species. But it can be rare to find a perfect print. The best conditions for finding tracks occur in fresh snow or in shallow mud after rain. Of course, most tracks in the countryside are made by domestic mammals, like dogs, cats, sheep and cows, so it is important to be able to recognise these.

(b) Droppings: Both the look and smell of droppings can be distinctive.

(c) Feeding signs: Gnawed hazelnuts, chopped grass and stripped fir cones can all be useful evidence of the presence of a range of small mammals.

(d) Bat identification: Using a bat detector, the ultrasonic calls made by hunting bats can be heard and plotted on a sonogram. The habitat, time of emergence and flight pattern all provide further clues.

Mammal Identification Courses

Each Eco-Skills course is part of a learning framework.. You can see the course level descriptions here

FSC run regular Mammals Identification Courses throughout spring and summer. Each course specialises in a group of mammals, such as bats, deer, badgers, dormice or the mammals of the riverside.For details of mammal courses, and to learn more about Mammal Identification, click the button above.

The Mammal Society and Bat Conservation Trust are associated with many courses at FSC centres.

Know your Bats!

In Britain we have 18 species of bat, all of which are insectivores, but 1300 species exist worldwide. Many of our native bats are under threat, due to loss of food supply and the loss of roosts and habitats. Bats are fascinating animals, but elusive because they are invisible and inaudible to us most of the time. On FSC Bat Identification courses you will learn how bat detectors can be used to identify bats in flight, using their echolocation calls

Hedgehog Action 

Our hedgehog population has been declining drastically in the UK, one of the main reasons behind this decline being our fences and walls are becoming more secure, restricting their movement and reducing the amount of land available to them.
We have already lost a third of our hedgehogs since the millennium. FSC Rhyd-y-creuau  in Snowdonia has recently introduced a hedgehog highway, and the UK now has a road sign featuring a hedgehog, warning drivers to keep a look out for small animals on the road.

FSC Biodiversity Newsletter

Sign up to the FSC Biodiversity Newsletter to hear about:

  • Subsidised BioLinks courses and events before we advertise them publicly.
  • News and blogs from our BioLinks and Generation Green projects.
  • Exciting new natural history courses from the FSC, including exclusive discount codes for subscribers.
  • Our extensive (and growing) range of natural history publications, including details of sales and earlybird offers.

Identification resources:

FSC Land mammals chart

FSC Mammal tracks and signs chart

FSC Bats chart

FSC Cetaceans and seals chart

The Mammal Society are encouraging people to download and use the mammal mapper to enable you to record signs and sightings of mammals in the UK.