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.