Freshwater pearl mussels spend their adult lives anchored to the river bed, filtering water through their gills and improving the quality of the water for other species.

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.

Once widespread, this attractive plant has declined as a result of modern agricultural practices and is now only found in four sites in South East England.

The markings of the peacock are unmistakeable - big, blue 'eyes' just like a peacock's tail feathers. It can be seen feeding on flowers all year-round during warm spells, and…

Large scale drainage in the UK has seen a massive reduction in the range of this sensitive aquatic plant which now only occurs in around 50 sites in England.

Bladder campion is so-called for the bladder-like bulge that sites just behind the five-petalled flower - this is actually the fused sepals. Look for it on grasslands, farmland and along hedgerows…

The rare heath fritillary was on the brink of extinction in the 1970s, but conservation action turned its fortunes around. It is still confined to a small number of sites in the south of England,…

A true wildlife 'hotel', Honeysuckle is a climbing plant that caters for all kinds of wildlife: it provides nectar for insects, prey for bats, nest sites for birds and food for small…

The rare smooth snake can only be found at a few heathland sites in the UK. It looks a bit like an adder, but lacks the distinctive zig-zag pattern along its back.

The English oak is, perhaps, our most iconic tree: the one that almost every child and adult alike could draw the lobed leaf of, or describe the acorn fruits of. A widespread tree, it is prized…

Unsurprisingly, the chalkhill blue can be found on sunny, chalk grassland sites in southern England. Clouds of this beautiful blue butterfly may be seen fluttering around low-growing flowers.