Look out for this tiny crab under rocks and boulders on rocky shores - you'll have to look closely though, they're pretty well camouflaged!

A small and delicate plant of chalk grasslands, Fairy flax can be seen in bloom from May to September - look out for its nodding, white flowers.

Although introduced by humans, the fallow deer has been here so long that it is considered naturalised. Look out for groups of white-spotted deer in woodland glades.

With club-shaped leaflets on its fronds, wall-rue is easy to spot as it grows out of crevices in walls. Plant it in your garden rockery to provide cover for insects.

The alder fly is a blackish invertebrate, with delicately veined wings that it folds over its body like a tent. It can be found near ponds and slow-flowing rivers; the larvae living in the silt at…

In early spring, listen out for the 'chiff chaff chiff chaff' song of the appropriately named chiffchaff. It can be heard in woodland, scrub, parks and gardens across the UK.

In spring and summer, look out for 'cuckoo-spit' - the frothy mass of bubbles that appears on plant stems everywhere. This is actually the protective covering for the nymphs of the tiny…

The lesser spotted woodpecker is the smallest of the UK's woodpeckers. Listen out for its drumming, which is quieter than that of the great spotted woodpecker, in woodland, parks , orchards…

The striking black-and-white checks of the marbled white are unmistakeable. Watch out for it alighting on purple flowers, such as field scabious, on chalk and limestone grasslands and along…

A dark, stocky warbler, the Cetti's warbler is most likely to be heard, rather than seen - listen out for its bubbling song among willow, marsh and nettles.