The Arctic tern is famed for its aggression towards any that would disturb its nest - it will dive-bomb intruders with its sharp beak. Large, noisy colonies can be found on the Farne Islands and…

A scarce but distinctive brown seaweed with curved, funnel-shaped fronds. It is a warmer water species at the northern edge of its range on the south coast of England.

The Leisler's bat flies fast and high near the treetops, but you might also spot it flying around lamp posts, looking for insects attracted to the light.

The blackbird of the mountains, ring ouzels can be found breeding on upland moors and rocky crags in summer.

A delicate, small plant of woodlands and hedgerows, wood-sorrel has distinctive, trefoil leaves and white flowers with purple veins; both fold up at night.

As the only crow with a red bill and red legs, the all-black chough is easy to identify. But it's harder to spot: there are only small, coastal populations in Scotland, Ireland, Wales,…

The common pipistrelle is so small, it can fit into a matchbox! Despite its size, it can easily eat 3,000 insects a night: look for it flitting around the garden or a lit lamp post as it chases…

Traditionally a coastal species, Lesser sea-spurrey has spread inland, taking advantage of the winter-salting of our roads. Its pink-and-white flowers bloom in summer.

Large scale drainage in the UK has seen a massive reduction in the range of this sensitive aquatic plant which now only occurs in around 50 sites in England.