RiverFish

Bullhead · Cottus gobio

Bullhead in the Main River Tone

Largest measured bullhead: 10.7 cm

The largest bullhead measured in Environment Agency surveys of the Main River Tone was 10.7 cm, recorded at Bulland Lodge on 1 July 2010.

Across 2,720 measured bullhead, the median measured length was 5.6 cm.

Surveyors recorded weights for 105 bullhead. The median was 0.2 oz (0.005 kg) and the largest recorded weight was 0.4 oz (0.012 kg).

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

See bullhead records across England →

Most recent observation30 September 2025Roughmoor (Te)
Largest measured bullhead
10.7 cm
Median length
5.6 cm
Fish measured
2,720
Survey locations
17

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
10.7 cm1 Jul 2010Bulland Lodge122566
9.1 cm25 Aug 1992Bulland Lodge79991
9 cm8 May 2014Bulland Lodge140740
8.7 cm2 Sept 2021Upstream Tracebridge160170
8.7 cm16 Aug 2018Ash Farm (Salmon Project)153061
8.7 cm7 May 2015Bulland Lodge144656
8.7 cm11 Jun 2014Upstream Tracebridge141078
8.7 cm11 Jun 2014Upstream Tracebridge141078
8.7 cm4 Sept 1992Upstream Tracebridge80016
8.7 cm26 Aug 1992Waterrow79992

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
Roughmoor (Te)9 Oct 200330 Sept 202512
Bulland Lodge25 Aug 199229 Aug 202515
Bathpool12 Sept 200619 Sept 20249
Upstream Tracebridge4 Sept 19922 Sept 20214
Greenham (Se-03)16 Apr 200329 Jul 20214
Ash Farm (Salmon Project)1 Jun 200616 Aug 20188
Bradford on Tone21 May 200818 Jun 20142
Harpford Bridge11 Apr 20003 Jun 20144
Waterrow26 Aug 19928 May 20144
Priorswood (Te)11 Sept 200313 Sept 20074
Hornshay Farm at Nynehead (Se-03)9 Sept 19947 Jun 20074
Parsonage Farm (Te)22 Sept 20034 Aug 20064
Downstream Nynehead Weir (Salmon Project)1 Jun 20061 Jun 20061
Marshes Farm7 Sept 20017 Sept 20011
Incline Cottages8 Sept 19948 Sept 19941
Trefusis Farm1 Sept 19941 Sept 19941
Winkleigh3 Sept 19923 Sept 19921

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

1992–2025

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 2,720 measured fish were spread across different length ranges.

Smallest
1.9 cm
Lower quarter
4.7 cm
Median
5.6 cm
Upper quarter
6.5 cm
Largest
10.7 cm

Lengths are direct survey measurements rather than anglers’ catches.

Fish weighed by surveyors

Measured weight summary

Recorded weights were available for 105 bullhead. This is a subset of the measured fish and may not represent the whole population.

Lightest
0 oz (0.001 kg)
Lower quarter
0.1 oz (0.003 kg)
Median
0.2 oz (0.005 kg)
Upper quarter
0.2 oz (0.007 kg)
Heaviest
0.4 oz (0.012 kg)

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

More fish in this river

Explore the Main River Tone

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

Brown / sea trout European eel Stone loach Minnow Atlantic salmon Grayling

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 →