This striking duck was introduced to the UK and is now established as a breeding bird in England.

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 muntjac deer was introduced into the UK from China in the 20th century. It has gained a stronghold in southeast England, where it can cause damage to our woods through browsing.

The whooper swan is a very rare breeding bird in the UK, but has much larger populations that spend winter here after a long journey from Iceland. It has more yellow on its yellow-and-black bill…

These distinctive beetles are often found around dead birds and small mammals.

Also known as the two-coloured mason bee, this beautiful bee is famous for nesting in old snail shells.

The common rosefinch is a rare visitor to the UK, usually passing through in autumn.

This charming little warbler is an increasingly common sight in autumn, when migrants pass through the UK.