RiverFish

Bullhead · Cottus gobio

Bullhead in the River Colne

Largest measured bullhead: 9.9 cm

The largest bullhead measured in Environment Agency surveys of the River Colne was 9.9 cm, recorded at Earls Colne FGS on 24 May 1999.

Across 1,229 measured bullhead, the median measured length was 6.3 cm.

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

See bullhead records across England →

Most recent observation16 June 2026Blue Bridge · 9 fish
Largest measured bullhead
9.9 cm
Median length
6.3 cm
Fish measured
1,229
Survey locations
23

Individual EA measurements

Largest measured bullhead

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

LengthSurvey dateSurvey locationSurvey ID
9.9 cm24 May 1999Earls Colne FGS14014
9.9 cm1 Sept 1987Box Mill13916
9.7 cm24 May 2011Chalkney Mill126323
9.6 cm29 Jun 2011Downstream New Bridge126782
9.5 cm8 Jun 2023Downstream New Bridge162726
9.5 cm26 Apr 2017Spring Lane150419
9.5 cm12 Jun 2008Maplestead Mill111319
9.3 cm6 Jun 2014Brook Street Farm141592
9.3 cm2 May 2014Broom House140743
9.3 cm4 May 2010Wakes Colne Viaduct121659

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 surveyedFirst recordedLast recordedVisits finding bullhead
Blue Bridge1 Jun 200516 Jun 20263
Nunnery Bridge14 Jun 201111 Jun 20264
Brook Street Farm10 Sept 198710 Jun 20269
Box Mill1 Sept 19873 Jun 202611
Wakes Colne Viaduct30 Apr 19992 Jun 202615
Fordstreet13 Aug 198714 May 20268
Spring Lane27 Jul 19877 May 202615
Earls Colne FGS19 Aug 19876 May 202612
Cooks Mill13 May 201428 Apr 20264
Downstream New Bridge1 Aug 19908 Jun 20239
Broom House21 May 20087 Jun 20234
Chalkney Mill19 May 19992 Jun 20234
Cricket Ground24 Jul 199024 May 20236
The Hedinghams15 Jun 201115 Jun 20111
Maplestead Mill8 Sept 19878 Jun 20117
Swanscombe Farm3 May 199618 Jun 20082
Halstead28 May 199910 Jun 20083
Elms Hall2 Jun 20055 Jun 20082
Fiddlers Mill17 May 20052 Jun 20082
Upstream A12 Bridge23 Apr 199613 May 20083
Castle Park29 Apr 200529 Apr 20051
Bathing Pool13 May 200213 May 20021
Does Corner19 Sept 199019 Sept 19901

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

1987–2026

Survey records by year

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

Fish measured by surveyors

Measured length distribution

See how the 1,229 measured fish were spread across different length ranges.

Smallest
2.5 cm
Lower quarter
5.6 cm
Median
6.3 cm
Upper quarter
7.2 cm
Largest
9.9 cm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the River Colne

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

Roach European eel Gudgeon Dace Pike Perch

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 →