1. Pied wagtails wag their tails almost constantly, but no one is certain why this is. However, it is thought to be a behaviour developed for social signalling.

2. Pied wagtails are insectivores and opportunists. They feed on flying insects and those that live on the ground, but will search for easy pickings - insects caught in car radiator grills, for example.

3. During the winter, pied wagtails form large roosts to keep warm at night. The largest roosts may hold as many as 4,000 individuals!

4. Pied wagtails have a reputation for choosing unusual nest sites, including cars, greenhouses and abandoned machinery.

5. During the winter months, adult males have feeding territories, which they defend fiercely when food is scarce.

6. Pied wagtails can be seen in a wide variety of habitats, and are just as comfortable in urban environments as they are beside streams and reedbeds.

7. During a particularly cold winter, pied wagtails living in northern upland areas will leave and fly south, sometimes as far as North Africa.

8. In courtship, two or more males will chase a female in a dancing, undulating flight.

9. Pied wagtails build their nests out of twigs, grass, dead leaves and moss with a lining of hair, wool and feathers.

10. Female pied wagtails build their nests with no assistance from males, but both parents feed their young once they have hatched.