This slim fish is usually found on gravelly parts of the seabed, close to shore, but can turn up in rockpools.

The Marsh helleborine is a beautiful orchid of fens, wet grassland and dune slacks. Growing in profusion in places, look for reddish stems and white-and-pink flowers.

Red squirrels are native to the UK but are a lot rarer than their grey cousins. They live in a few special places across the UK thanks to reintroduction projects.

The delicate, tube-like, violet-blue flowers of Skullcap bloom from June to September in damp places, such as marshes, fens, riverbanks and pond margins.

Ground-elder was likely introduced into the UK by the Romans and has since become naturalised. A medium-sized umbellifer, it is an invasive weed of shady places, gardens and roadsides.

This dainty white butterfly is now only found in a few parts of Britain, where it flutters slowly through woodland clearings.