This small, white heron is an increasingly common sight in parts of the UK as it spreads north from continental Europe.

This small, round sea urchin is (unsurprisingly!) green in colour and can be found on rocky shores around the UK.

Despite its dazzling colouration, this fabulous nudibranch can be easily missed, due to its small size!

This large shrike visits the UK in small numbers each year, passing through on migration or spending the winter here.

This small finch nests on moorlands and coastal crofts, spending the winter on the coast. The UK population has declined dramatically.

This small duck is an uncommon winter visitor to the UK, where they're usually found on lakes, reservoirs and gravel pits.

The brown hairstreak is an elusive butterfly that spends much of its time in the treetops feeding on aphid honeydew.

Look for the small, pink, pea-shaped flowers of Common restharrow on chalk and limestone grasslands, and in coastal areas, during summer.

Enchanter's nightshade is a hairy plant, with rounded leaves that taper to a fine tip, and clusters of small, pinky-white flowers in summer.