Blink and you may miss the fantastic kingfisher! It's often seen as a flash of blue flying low over a river.

The Atlantic salmon spends most of its life at sea, but makes an epic journey back to the river or stream in which it hatched to spawn. Look out for it in freshwater rivers in the north and west…

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 chocolate-brown, plump dipper can often be seen bobbing up and down on a stone in a fast-flowing river. It feeds on underwater insects by walking straight into, and under, the water.

The common clubtail is on the wing in spring and summer. It is an elusive dragonfly that is easiest to see when it first emerges. It can be found along rivers in Southern England and Wales.

Famously predatory, the long, slender pike will lurk among the vegetation of a river or lake, bursting out with ferocious speed to catch its prey. Look out for it across the UK.

The greylag goose can be easily spotted around parks, gravel pits and river valleys, but these populations tend to be semi-tame, having been reintroduced. Truly wild populations can be found in…