RiverFish

Roach · Rutilus rutilus

Roach in the Grand Union Canal

Largest measured roach: 29.8 cm

The largest roach measured in Environment Agency surveys of the Grand Union Canal was 29.8 cm, recorded at Cosgrove on 4 April 1990.

Across 16,882 measured roach, the median measured length was 9.3 cm.

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

See roach records across England →

Most recent observation1 February 1994Cosgrove · 720 fish
Largest measured roach
29.8 cm
Median length
9.3 cm
Fish measured
16,882
Survey locations
16

Individual EA measurements

Largest measured roach

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

LengthSurvey dateSurvey locationSurvey ID
29.8 cm4 Apr 1990Cosgrove28793
29.3 cm24 Nov 1993Ivinghoe Lock28797
28.8 cm1 Feb 1994Cosgrove28809
28.8 cm22 Dec 1993Wolverton28808
26.8 cm24 Nov 1993Ivinghoe Lock28797
26.3 cm24 Nov 1993Ivinghoe Lock28797
26.3 cm28 Mar 1990Wolverton28792
25.8 cm13 Dec 1993Three Locks28801
25.8 cm24 Nov 1993Ivinghoe Lock28797
25.8 cm4 Apr 1990Cosgrove28793

Lengths are direct survey measurements. RiverFish does not estimate fish weights from length.

Explore the river

Where roach were found

Each point marks a survey location with at least one roach 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 roach
Cosgrove4 Apr 19901 Feb 19942
Stoke Bruerne23 Mar 199031 Jan 19942
Grafton Regis3 Apr 199028 Jan 19942
Yardley Gobion GUC2 Apr 199023 Dec 19932
Wolverton28 Mar 199022 Dec 19932
Bradwell Waste Tip27 Mar 199020 Dec 19932
Linford Manor Park25 Mar 199017 Dec 19932
Woolstone30 Mar 199016 Dec 19932
Simpson22 Mar 199015 Dec 19932
Water Eaton21 Mar 199014 Dec 19932
Three Locks19 Mar 199013 Dec 19932
Old Linslade7 Dec 19937 Dec 19931
Grove Lock14 Mar 19902 Dec 19932
Stoke Hammond20 Mar 199030 Nov 19932
Ivinghoe Lock13 Mar 199024 Nov 19932
Leighton Buzzard Canal15 Mar 199015 Mar 19901

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

1990–1994

Survey records by year

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

Fish measured by surveyors

Measured length distribution

See how the 16,882 measured fish were spread across different length ranges.

Smallest
3.8 cm
Lower quarter
7.3 cm
Median
9.3 cm
Upper quarter
11.8 cm
Largest
29.8 cm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the Grand Union Canal

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

Perch Common bream Gudgeon Ruffe Pike Bullhead

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 →