Introduced into the UK in the 19th century, the diminutive little owl can now be seen along hedgerows, on farmland and in parkland across England and Wales. It often perches on a pole or rock,…

Look for Water avens in damp habitats, such as riversides, wet woodlands and wet meadows. It has nodding, purple-and-orange flowers that hang on delicate, purple stems.

The white-clawed crayfish is a freshwater, bronze-coloured crustacean with pale undersides to its claws - hence the name. It is under threat from an invasive and introduced species of crayfish.…