The gudgeon is a bottom-dwelling fish, similar to the stone loach, but with only two whisker-like barbels near its mouth. These sensory organs help it to find its prey in the sand and gravel of…

The stone loach is notoriously hard to spot - not only is it mostly nocturnal, it is also well camouflaged and can partially bury itself in the riverbed. It uses its whisker-like barbels to find…

A very rare species, this moth is now limited to one site in the UK. Males can be a striking reddish buff in colour.

A delicate wader, Red-necked phalaropes are as comfortable swimming as they are on land. Unusually for birds, the females are more brightly coloured than the males.

A streaky brown bird, the reed bunting can be found in wetlands, reedbeds and on farmland across the UK. Males sport black heads and a white 'moustache'.

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.

The bearded tit is an unmistakable cinnamon-coloured bird of reedbeds in the south, east and north-west of England. Males actually sport a black 'moustache', rather than a beard!

The house sparrow is a familiar, streaky brown bird of towns, parks and gardens. Males sport a grey cap and black bib, the size of which indicates their status.

An attractive, green-and-yellow bird, the siskin regularly visits birdtables and feeders in gardens. Look for the bright yellow barring on its black wings, and the black crown of the males.

The bar-tailed godwit winters in the UK in the thousands; look for it around estuaries like the Thames and Humber. In spring, the males display arresting breeding plumage, with brick-red heads,…