RiverFish

Bullhead · Cottus gobio

Bullhead in the River Main Plym

Largest measured bullhead: 8.7 cm

The largest bullhead measured in Environment Agency surveys of the River Main Plym was 8.7 cm, recorded at Ham on 25 July 2017.

Across 450 measured bullhead, the median measured length was 5.8 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 Main Plym.

See bullhead records across England →

Most recent observation7 August 2025Ham · 18 fish
Largest measured bullhead
8.7 cm
Median length
5.8 cm
Fish measured
450
Survey locations
7

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
8.7 cm25 Jul 2017Ham151203
8.7 cm14 Jun 2013Plym Bridge136402
8.3 cm17 Jul 2015Ham145495
8.2 cm17 Jul 2015Ham145495
8 cm25 Jul 2017Ham151203
8 cm25 Jul 2017Ham151203
8 cm17 Jul 2015Ham145495
7.9 cm1 Aug 2019Ham155401
7.9 cm1 Aug 2019Ham155401
7.9 cm17 Jul 2015Ham145495

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
Ham23 Jan 19827 Aug 202518
Great Shaugh Wood7 Jul 19824 Jul 20259
Plym Bridge29 Jul 198220 Jun 20259
Carne Wood21 Jul 202321 Jul 20231
Upstream Ham13 Jul 202313 Jul 20231
Colwill Wood28 Jun 202328 Jun 20231
Bickleigh30 Jun 200630 Jun 20061

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

1982–2025

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 450 measured fish were spread across different length ranges.

Smallest
1.5 cm
Lower quarter
4.2 cm
Median
5.8 cm
Upper quarter
6.5 cm
Largest
8.7 cm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the River Main Plym

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

European eel Brown / sea trout Atlantic salmon Minnow Flounder

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 →