RiverFish

Bleak · Alburnus alburnus

Bleak in the River Medway

Largest measured bleak: 19.2 cm

The largest bleak measured in Environment Agency surveys of the River Medway was 19.2 cm, recorded at Bewleys Weir on 23 September 2002.

Across 4,444 measured bleak, the median measured length was 7.1 cm.

Surveyors recorded weights for 95 bleak. The median was 0.4 oz (0.01 kg) and the largest recorded weight was 1.3 oz (0.037 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 Medway.

See bleak records across England →

Most recent observation21 July 2026Sovereign Way Tonbridge · 72 fish
Largest measured bleak
19.2 cm
Median length
7.1 cm
Fish measured
4,444
Survey locations
17

Individual EA measurements

Largest measured bleak

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

LengthSurvey dateSurvey locationSurvey ID
19.2 cm23 Sept 2002Bewleys Weir72757
16.7 cm24 Jun 2010Yalding Leas122461
16 cm28 Aug 2025Yalding Leas178703
15.8 cm28 Aug 2025Yalding Leas178703
15.6 cm14 Oct 2024Fordcombe168470
15.5 cm27 Sept 2004Yalding Leas83137
15.4 cm15 Aug 2003Fordcombe77770
15.3 cm17 Aug 2004Bewleys Weir82942
15.2 cm5 Jun 2007Bewleys Weir106456
15.1 cm28 Aug 2025Yalding Leas178703

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

Explore the river

Where bleak were found

Each point marks a survey location with at least one bleak 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 bleak
Sovereign Way Tonbridge1 Sept 201021 Jul 202614
Golden Green7 Sept 200516 Jul 202617
Tovil21 Jul 200815 Jul 202613
Teston21 Jul 200815 Jul 202614
Yalding Leas27 Sept 200418 Jun 202617
Penshurst22 Nov 200116 Oct 202518
Fordcombe15 Aug 200315 Oct 202512
D/s Ashurst Road Bridge13 Aug 200718 Sept 20257
Tonbridge Juvenile Fish Seine Netting Survey20 Jul 201228 May 20255
Maidstone Juvenile Fish Seine Netting Survey2 Jul 201520 Aug 20244
Hampstead Lock Juvenile Fish Seine Netting Survey17 Aug 201814 Jul 20233
Yalding Juvenile Fish Seine Netting Survey31 Aug 20128 Aug 201610
East Farleigh29 Jul 201429 Jul 20141
Tonbridge Juvenile Fish Kick Sampling Survey20 Jul 201220 Jul 20121
Maidstone Juvenile Fish Kick Sampling Survey20 Jul 201220 Jul 20121
Bewleys Weir23 Sept 20023 Sept 20098
Hartfield29 May 200729 May 20071

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

2001–2026

Survey records by year

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

Fish measured by surveyors

Measured length distribution

See how the 4,444 measured fish were spread across different length ranges.

Smallest
1.3 cm
Lower quarter
5.4 cm
Median
7.1 cm
Upper quarter
9.2 cm
Largest
19.2 cm

Lengths are direct survey measurements rather than anglers’ catches.

Fish weighed by surveyors

Measured weight summary

Recorded weights were available for 95 bleak. This is a subset of the measured fish and may not represent the whole population.

Lightest
0 oz (0.001 kg)
Lower quarter
0.2 oz (0.0065 kg)
Median
0.4 oz (0.01 kg)
Upper quarter
0.6 oz (0.017 kg)
Heaviest
1.3 oz (0.037 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 Medway

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

Chub Gudgeon Roach Perch Dace Minnow

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 →