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

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.

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.

As its name suggests, the scarlet elfcup is a bright red, cup-shaped fungus. It is widespread, but scarce, and can be found on fallen twigs and branches, in shady, damp places.

A great way to get up close and personal with the magnificent osprey is via one of the many nestcams set-up in the places that it breeds: Scotland, Cumbria, Wales and the East Midlands.

With a silvery body, and purple, pink and bluish streaks down its flanks, the rainbow trout lives up to its name. Popular with anglers, it is actually an introduced species in the UK.

A handsome fish, the tench has olive-green flanks, powerful fins and distinctive red eyes. It can be found in lowland lakes and slow-flowing rivers around the UK.