Look for the wood warbler singing from the canopy of oak woodlands in the north and west of the UK. Green above, it has a distinctive, bright yellow throat and eyestripe.

Beavers are the engineers of the animal world, creating wetlands where wildlife can thrive. After a 400-year absence, beavers are back in Britain!

You're more likely to see the attractive, brightly coloured caterpillars than the mullein moth itself.

The marsh hair moss is the largest moss in the UK. Look out for it in damp woodland and on boggy heathlands where it forms large, green and spikey 'cushions'.

The river lamprey is a primitive, jawless fish, with a round, sucker-mouth which it uses to attach to other fish to feed from them. Adults live in the sea and return to freshwater to spawn.

These winter visitors are close relatives of the chaffinch and can often be found in the same flocks, where their white rump and nasal calls give them away.

Barnacles are so common on our rocky shores that you've probably never really noticed them. They're the little grey bumps covering the rocks that hurt your feet when you're…

Sea potatoes may have a funny name, but they are perfectly adapted for life in the sand. They are a type of sea urchin that live in a burrow in the sand, feeding on dead animals and plants using…

The common green lacewing is a lime green, delicate insect, with translucent, intricately veined wings. It is common in gardens and parks, where it helps to control aphid pests.

These little critters are related to the woodlice you find in your garden and play a very important role on rocky shores.

A scarce tree of England and Wales, the large-leaved lime is the rarest of our native limes. It is tall and broad, and can be found in forests and parks, where it is frequently planted.