Bullhead · Cottus gobio

Bullhead in the Wraysbury River

Largest measured bullhead: 6.4 cm

The largest bullhead measured in Environment Agency surveys of the Wraysbury River was 6.4 cm, recorded at Harmondsworth Moor on 4 August 2004.

Across 6 measured bullhead, the median measured length was 5 cm.

RiverFish uses Environment Agency survey measurements rather than rod-and-line angling records. These figures show fish measured during EA surveys of the Wraysbury River.

See bullhead records across England →

Most recent observation15 May 2024Harmondsworth Moor

Largest measured bullhead: 6.4 cm
Median length: 5 cm
Fish measured: 6
Survey locations: 3

Individual EA measurements

Largest measured bullhead

The largest individual measurements in this river and species dataset. Equal measurements are retained as separate surveyed fish.

Length	Survey date	Survey location	Survey ID
6.4 cm	4 Aug 2004	Harmondsworth Moor	80906
5.4 cm	4 Aug 2004	Harmondsworth Moor	80906
5.4 cm	4 Aug 2004	Harmondsworth Moor	80906
4.5 cm	4 Aug 2004	Harmondsworth Moor	80906
3.5 cm	4 Aug 2004	Harmondsworth Moor	80906
3.4 cm	4 Aug 2004	Harmondsworth Moor	80906

Lengths are direct survey measurements. RiverFish does not estimate fish weights from length.

Explore the river

Where bullhead were found

Each point marks a survey location with at least one bullhead record.

Choose a point on the map to see what was recorded there.

Map points are approximate and don’t show fishing access. Check local permissions before visiting.

Place surveyed	First recorded	Last recorded	Visits finding bullhead
Harmondsworth Moor	3 Sept 2003	15 May 2024	14
Heathrow Wraysbury River Zone H	22 Oct 2019	22 Oct 2019	1
Heathrow Wraysbury River Zone F	22 Oct 2019	22 Oct 2019	1

Choose a point or table row to see the location. More survey visits can mean more records, but not necessarily more fish.

2003–2024

Survey records by year

Each bar shows how many survey visits recorded bullhead that year.

103

104

005

106

107

008

109

110

111

112

113

114

115

016

017

118

219

020

021

022

123

124

Fish measured by surveyors

Measured length distribution

See how the 6 measured fish were spread across different length ranges.

Smallest: 3.4 cm
Lower quarter: 3.8 cm
Median: 5 cm
Upper quarter: 5.4 cm
Largest: 6.4 cm

0–99 mm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the Wraysbury River

Compare other species with enough survey and measurement data for a detailed page.

Chub Dace Gudgeon Minnow Perch Pike

Before you fish

Good to know

These are past survey records, so the fish present today may be different. Map points are approximate—check local access, permissions and fishing rules before visiting.

Learn how RiverFish uses the data →