Bullhead - Cottus gobio

Alternative names
Miller's Thumb
Description

The European Bullhead is a small fish, with a large mouth, large pectoral fins, prominent eyes and a wide flattened head; hence the common names 'Bullhead' and 'Miller's Thumb'. They are brownish in colour with mottling or barring, and pale undersides. During the spawning period males become black in colour with a white-tipped dorsal fin, and females become plump. They rarely grow to more than 10 cm long. 

Identification difficulty
Habitat

Occurs in freshwater streams, rivers and lakes with hard stony substrates and shows a preference for fast flowing, shallow water bodies. The large pectoral fins enable Bullheads to hold their position in fast flowing water. 

When to see it

All year round but most readily seen around dusk. 

Life History

They lay their eggs in March and April, and the male guards the eggs until they hatch (although once they hatch he may eat a few of the youngsters if they come close enough). 

UK Status

The Bullhead is widely distributed in England and Wales but in Scotland is only known from the Forth and Clyde catchments.  It is less common in the rest of Europe. Red Data Book species.

VC55 Status

Fairly common in Leicestershire and Rutland where it is widely distributed in both smaller and larger rivers; found especially in the Soar, Gwash, Chater, Swift, Charnwood streams including Black Brook, Rothley Brook, Wreake, Eye, Langham Brook, eastern and western Sence, Mease/Gilwiskaw, Hooborough Brook, Gaddesby Brook and Sibson Brook.

Leicestershire & Rutland Map

MAP KEY:

Yellow squares = NBN records (all known data)
Coloured circles = NatureSpot records: 2020+ | 2015-2019 | pre-2015

UK Map

Species profile

Common names
Miller's Thumb, Bullhead
Species group:
Fish
Kingdom:
Animalia
Order:
Scorpaeniformes
Family:
Cottidae
Records on NatureSpot:
22
First record:
11/09/1997 (Environment Agency)
Last record:
09/04/2023 (Bell, Melinda)

Total records by month

% of records within its species group

10km squares with records

The latest images and records displayed below include those awaiting verification checks so we cannot guarantee that every identification is correct. Once accepted, the record displays a green tick.

In the Latest Records section, click on the header to sort A-Z, and again to sort Z-A. Use the header boxes to filter the list.

Latest images

Latest records