It's easy to see where the blue shark got its name from. These sleek, elegant sharks have beautiful metallic blue backs which provide brilliant camouflage out in the open ocean.

The rare Adonis blue can be spotted on sunny chalk grasslands throughout summer. Males are a dazzling sky-blue in colour, while females are duller brown.

Often confused with the larger but similarly shaped lion’s mane jellyfish, the blue jellyfish can be colourless when young and develop a striking blue-purple bell as it matures.

Despite its name, the large blue is a fairly small butterfly, but the largest of our blues. It was declared extinct in 1979, but reintroduced in the 1980s and now survives in southern England.

Native oysters are a staple of our seas and our plates - but our love of their taste has lead to a sharp decline all around the UK.

The dazzling silver-studded blue is a rare butterfly of heathland habitats, mainly in southern England. It has undergone severe population declines in recent years.

Living up to its name, the common blue damselfly is both very common and very blue. It regularly visits gardens - try digging a wildlife-friendly pond to attract damselflies and dragonflies.

Oyster mushrooms are shell shaped fungi that grow in tiers or fabulous clusters on dead trees or stumps. Unlike many fungi, these mushrooms are not seasonal and can be found all year round,…

This is a predominantly subtidal species but can be found on the lowest parts of a sheltered rocky shore in summer.

The kingfisher blue stripes of a blue-rayed limpet are a magical sight whilst rockpooling - you'll need to go on a very low tide though as their favourite home is on kelp.