Bullhead · Cottus gobio

Bullhead in the River Idle

Largest measured bullhead: 10 cm

The largest bullhead measured in Environment Agency surveys of the River Idle was 10 cm, recorded at Bawtry on 4 May 2011.

Across 65 measured bullhead, the median measured length was 7.1 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 Idle.

See bullhead records across England →

Most recent observation23 August 2024Bawtry

Largest measured bullhead: 10 cm
Median length: 7.1 cm
Fish measured: 65
Survey locations: 5

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
10 cm	4 May 2011	Bawtry	126161
9.3 cm	2 May 2014	Eaton	140863
9.2 cm	8 May 2014	Bawtry	140757
9 cm	13 Apr 2017	Chain Bridge Lane	150347
9 cm	11 Apr 2017	Eaton	150339
8.7 cm	8 May 2014	Bawtry	140757
8.5 cm	13 Apr 2017	Chain Bridge Lane	150347
8.5 cm	11 Apr 2017	Eaton	150339
8.5 cm	8 May 2014	Bawtry	140757
8 cm	13 Apr 2017	Chain Bridge Lane	150347

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
Bawtry	4 May 2011	23 Aug 2024	4
Chain Bridge Lane	20 Sept 2005	21 Aug 2024	5
Mattersey Priory	4 May 2011	13 Apr 2017	2
Tiln	19 Feb 1991	11 Apr 2017	3
Eaton	13 May 2009	11 Apr 2017	5

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

1991–2024

Survey records by year

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

191

092

093

094

095

096

097

098

099

000

001

002

003

004

105

006

007

008

309

210

311

012

013

214

015

016

517

018

019

020

021

022

023

224

Fish measured by surveyors

Measured length distribution

See how the 65 measured fish were spread across different length ranges.

Smallest: 3.5 cm
Lower quarter: 6.4 cm
Median: 7.1 cm
Upper quarter: 7.8 cm
Largest: 10 cm

0–99 mm

100–199 mm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the River Idle

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

European eel Roach Perch Pike Chub 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 →