The gadwall is a dabbling duck, feeding at the surface of shallow water by 'upending' - putting its head down and its bottom up! Only a small number of gadwall nest in the UK, but large…

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 Land caddis is the only caddisfly in the UK to spend its entire time on land, with no stage in water. Look in oak leaf litter over winter to see the grainy cases of the larvae, in which they…

Also known as the brown crab, this large crab is found around all UK shores and is identifiable by the distinctive pie-crust edge to its brown shell.

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.

A scarce and declining bird, the tree sparrow can be spotted on farmland and in woodlands; it is not an urban bird in the UK. It has a brown cap and black cheek-spots, unlike the similar house…

A pretty and distinctive little waterbird, the mandarin duck was introduced from the Far East as its name suggests. Oddly for a duck, it nests in trees, sometimes high above the water.

This well-camouflaged wader is a winter visitor to the UK, where it can be seen feeding on wetlands with a distinctive bobbing motion.