This striking duck was introduced to the UK and is now established as a breeding bird in England.

The tightly packed, thistle-like purple flower heads of common knapweed bloom on all kinds of grasslands. Also regularly called black knapweed, this plant attracts clouds of butterflies.

The harvest mouse is tiny - an adult can weigh as little as a 2p piece! It prefers habitats with long grass, but you are most likely to spot its round, woven-grass nests.

The oak marble gall wasp produces brown, marble-shaped growths, or 'galls', on oak twigs. Inside the gall, the larvae of the wasp feed on the host tissues, but cause little damage.

Traditionally a small finch of woodland and scrub, it appears that the redpoll is now moving into our gardens. It has a streaky brown body, red forehead and black bib, and mostly feeds on seeds.…

A familiar garden bird, the blue tit can be seen around bird tables and feeders, as well as in woodlands and parks. Listen out for its trilling, 'tsee-tsee-tsee' song. It is smaller than…

A tall orchid of woodland and scrub, the broad-leaved helleborine has greenish, purple-tinged flowers that look a little 'drooping'. Strongly veined, oval leaves spiral around its stem…

Looking like a short dandelion, but with a much rounder middle, colt's-foot is a 'weed' of waste ground and field edges that brightens up early spring with its sunshine-yellow…

The common spangle gall wasp produces a small, disc-shaped growth, or 'gall', on the undersides of oak leaves. Inside the gall, the larvae of the wasp feed on the host tissues, but cause…

The common carp is a very large fish that is popular with anglers due to its size and fighting spirit. It frequents ponds, gravel pits and lakes, but is not native to the UK, being introduced in…

The grey plover is similar to the golden plover, but as its name suggests, has a silver- and black-speckled back, rather than a gold one. It is only found at the coast and is mostly a winter…

The UK's smallest hawker, the Hairy dragonfly is mostly black in colour, but has a distinctively hairy thorax. It can be found in grazing marshes and flooded gravel pits, and along canals…