Guide to small river fish: where to see and how to identify

The finned dwellers, lurkers and sprinters of our rivers and streams are as varied and fascinating as any wildlife on dry land – our guide on small river fish looks common species found in British rivers, where to see and how to identify.


Here is our guide on small river fish found in British rivers, including best places to see and how to identify.

What species of fish are found in UK rivers?

Freshwater fish are found in rivers in the UK. Common species include small fish such as grayling, dace and brown trout. See more species below.



The ‘lady of the stream’ is one of our most beautiful fish. With a sail-like dorsal edged in red and shimmering spotted flanks, the grayling is believed in some cultures to feed on gold.

Grayling (Getty)




A sleek silver fish that thrives between beds of water crowfoot over fast gravel runs, the dace is a close relative of the chub but has a smaller mouth and concave edges to its fins. 

Dace (Getty)

Brook Lamprey

Having spent most of its life as a larva in the silt of the stream bed, the brook lamprey only develops into adult form to breed. The short-lived mature fish have mouth-parts but no digestive system.

Brook Lamprey
Brook Lamprey (Getty)

Brown Trout

The brown trout is often at its most beautiful in small streams where its delicate ink-dropped flanks glisten in the clear water. Much sought by anglers who use artificial flies to attract them.  

Brown trout
Brown trout (Getty)

Stone Loach

Widespread in clear water streams with sand or gravel beds, the eel-shaped stone loach is largely nocturnal and uses three pairs of barbels that surround an underslung mouth to search for food.

Stone loach
Stone loach (Getty)


In deeper, slower-moving streams, the brassy-flanked chub will grow surprisingly large. It is an unfussy eater with a large mouth and fearsome teeth that it uses to break down food.



Often abundant in well-oxygenated streams and rivers, they are a favoured food of kingfishers, herons and other fish. In late spring the males develop striking red bellies before breeding.   

Minnow (Getty)

Britain’s most beautiful river walks

The British countryside is filled with charming rivers, rich in wildlife and history. Discover a waterway walk near you with our round-up of the UK’s best riverside rambles.

Allan Water
Born from the Devonian rock of the Ochil Hills, the Allan Water spills for 22 miles through Stirlingshire and Perthshire, eventually joining the River Forth ©Alamy