Bullhead · Cottus gobio

Bullhead in England's Rivers

The largest recorded measurement is 64.6 cm (25.4 in), from Warmans Industrial Estate in River Calder on 22 August 2003.

Median length: 5.6 cm (2.2 in)
Fish measured: 257,715
Named waterways: 1,953
Latest observation: 30 Jul 2026

Direct individual measurements

Largest bullhead by waterway

Ranked by the largest individual measured in EA surveys. The sample size shows how many valid length measurements underpin each waterway's figures.

Rank	River or waterway	Largest	Median	Measured	Measured at
1	River CalderYorkshire and North East	64.6 cm (25.4 in)	6.5 cm (2.6 in)	1,281	22 Aug 2003Warmans Industrial Estate
2	River RodingSouth East	22 cm (8.7 in)	3.9 cm (1.5 in)	1,422	2 Aug 2005Crowther Nurseries
3	Morton BrookMidlands	17.5 cm (6.9 in)	5.7 cm (2.2 in)	21	11 Jul 1991Morton Brook
4	River ItchenSouth East	16.9 cm (6.7 in)	6.1 cm (2.4 in)	737	3 Sept 2008Bishopstoke Barge
5	River WallingtonSouth East	16.7 cm (6.6 in)	4.7 cm (1.9 in)	195	25 Jun 2001Whitedell Farm
6	Great Eau FMUAnglian	15.2 cm (6 in)	7.4 cm (2.9 in)	159	7 Apr 1992Claythorpe Gauging Station
7	River WithamAnglian	14.1 cm (5.6 in)	6.9 cm (2.7 in)	3,565	6 Sept 1985Sleeper Bridge (Witham)
8	River UckSouth East	13.6 cm (5.4 in)	5.7 cm (2.2 in)	835	18 Aug 2021Uckfield
9	River HolmeYorkshire and North East	13.2 cm (5.2 in)	7.5 cm (3 in)	2,665	27 Aug 2004Sands Recreation Ground
10	River GowyNorth West	13.1 cm (5.2 in)	8 cm (3.1 in)	206	22 Apr 2002Gwgo05

Equal maximum lengths are ordered by sample size. Measurements are shown as recorded and are not converted into estimated weights.

257,715 fish measured

Measured bullhead lengths

The median divides the measured sample in half. This distribution describes surveyed fish, not every bullhead living in England.

0–19 mm

729

20–39 mm

48875

40–59 mm

98089

60–79 mm

87493

80–99 mm

20813

100–119 mm

1659

120–139 mm

140–159 mm

160–179 mm

220–239 mm

640–659 mm

Only positive individual lengths that pass RiverFish's general measurement checks are included. Each bar covers a 20 mm range.

Latest EA evidence

Latest bullhead observations

The ten most recent survey visits that recorded bullhead in named waterways.

Date	River or waterway	Survey location	Fish recorded
30 Jul 2026	River Quin	Upstream Griggs Bridge	Not supplied
28 Jul 2026	River North Tyne	North Tyne at Riverhill farm	Not supplied
27 Jul 2026	River Swale	Great Langton DS of midbar	Not supplied
27 Jul 2026	River Swale	Great Langton RH of midbar	Not supplied
24 Jul 2026	Long Whatton Brook	Long Whatton	Not supplied
23 Jul 2026	River Weaver	Wewe25	Not supplied
23 Jul 2026	River Lee	Amwell Loop	Not supplied
22 Jul 2026	River Darent	Twitton Brook	7
21 Jul 2026	River Colne	Uxbridge	Not supplied
16 Jul 2026	River Colne	Watford M1 link road	Not supplied

A survey record confirms bullhead at that place and time. It does not show present-day abundance or fishing access.

30,719 positive survey visits

Survey distribution

EA surveys recorded bullhead at 8,482 locations across 1,953 named waterways represented on RiverFish.

Region	Waterways	Locations	Survey visits	Latest record
South West	518	1,864	7,991	10 Jul 2026
Midlands	360	1,537	4,677	24 Jul 2026
North West	329	1,304	4,444	23 Jul 2026
South East	309	1,489	5,022	30 Jul 2026
Yorkshire and North East	228	1,167	4,481	28 Jul 2026
Anglian	209	1,121	4,104	2 Jul 2026

908 detailed pages

Bullhead by river

Open any river-specific page for its measured lengths, largest surveyed individuals, locations and observation history.

Anglian 147 pages

Midlands 152 pages

North West 31 pages

South East 131 pages

South West 302 pages

Yorkshire and North East 145 pages

How to read this page

Survey measurements, not angling records

Environment Agency surveys are designed to monitor fish populations. Their largest measurement is not equivalent to a verified rod-and-line record, and the survey sample does not include every river or every bullhead.

Waterway groups with administrative or mixed-river labels are excluded from the headline national totals and rankings. Their eligible river-specific pages remain available in the directory so no published destination is hidden.

The fish records use the Environment Agency source snapshot dated 10 August 2026.

How RiverFish handles the data →