RiverFish

Bullhead · Cottus gobio

Bullhead in the River Tas

Largest measured bullhead: 10.9 cm

The largest bullhead measured in Environment Agency surveys of the River Tas was 10.9 cm, recorded at Tasburgh Mill Farm on 5 April 2005.

Across 3,017 measured bullhead, the median measured length was 5.8 cm.

Surveyors recorded weights for 2 bullhead. The median was 0.3 oz (0.0075 kg) and the largest recorded weight was 0.3 oz (0.008 kg).

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

See bullhead records across England →

Most recent observation2 April 2026Tasburgh Mill Farm · 43 fish
Largest measured bullhead
10.9 cm
Median length
5.8 cm
Fish measured
3,017
Survey locations
10

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
10.9 cm5 Apr 2005Tasburgh Mill Farm84419
10.7 cm15 May 2000Upstream Tasburgh Hall18712
10.6 cm13 Apr 2010Flordon Common121364
10 cm2 May 2024Downstream Stoke Mill166211
10 cm19 Apr 2022Downstream Forncett Street160991
10 cm22 Apr 2005Upstream Hempnall Beck84614
10 cm27 Apr 1987Tasburgh Mill Farm17407
9.9 cm5 Apr 2005Tasburgh Mill Farm84419
9.9 cm17 May 2000Markshall Bridge18718
9.9 cm27 Apr 1987Tasburgh Mill Farm17407

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
Tasburgh Mill Farm27 Apr 19872 Apr 202615
Flordon Common15 May 20031 Apr 202614
Downstream Stoke Mill7 Apr 19872 May 20249
Upstream Shotesham Park14 Apr 200530 Apr 20246
Markshall Bridge6 Apr 198725 Apr 20249
Downstream Forncett Street11 Apr 200519 Apr 20225
CEGB Trowse17 Sept 199227 Apr 20052
Upstream Hempnall Beck22 Apr 200522 Apr 20051
Upstream Tasburgh Hall24 Apr 19877 Apr 20055
Rainthorpe Hall16 Apr 198716 Apr 19871

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 3,017 measured fish were spread across different length ranges.

Smallest
1.1 cm
Lower quarter
4.9 cm
Median
5.8 cm
Upper quarter
6.8 cm
Largest
10.9 cm

Lengths are direct survey measurements rather than anglers’ catches.

Fish weighed by surveyors

Measured weight summary

Recorded weights were available for 2 bullhead. This is a subset of the measured fish and may not represent the whole population.

Lightest
0.2 oz (0.007 kg)
Lower quarter
0.3 oz (0.0072 kg)
Median
0.3 oz (0.0075 kg)
Upper quarter
0.3 oz (0.0078 kg)
Heaviest
0.3 oz (0.008 kg)

These are direct individual weights recorded by Environment Agency surveyors. Combined bulk weights are not included.

More fish in this river

Explore the River Tas

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

European eel Stone loach Roach Dace Pike Gudgeon

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 →