RiverFish

Bleak · Alburnus alburnus

Bleak in the River Old Windsor

Largest measured bleak: 14.1 cm

The largest bleak measured in Environment Agency surveys of the River Old Windsor was 14.1 cm, recorded at Old Windsor Upstream Fry on 21 August 2007.

Across 1,103 measured bleak, the median measured length was 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 River Old Windsor.

See bleak records across England →

Most recent observation3 September 2025Old Windsor Upstream Fry · 98 fish
Largest measured bleak
14.1 cm
Median length
3 cm
Fish measured
1,103
Survey locations
2

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
14.1 cm21 Aug 2007Old Windsor Upstream Fry108618
13.4 cm21 Aug 2007Old Windsor Upstream Fry108618
12.2 cm21 Aug 2007Old Windsor Upstream Fry108618
11.6 cm21 Aug 2007Old Windsor Upstream Fry108618
11.2 cm21 Aug 2007Old Windsor Upstream Fry108618
8.2 cm20 Sept 2006Old Windsor Downstream Fry111934
7.5 cm3 Sept 2025Old Windsor Upstream Fry178527
6.4 cm20 Sept 2006Old Windsor Downstream Fry111934
6.3 cm21 Aug 2012Old Windsor Downstream Fry135279
6.1 cm3 Sept 2025Old Windsor Upstream Fry178527

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
Old Windsor Upstream Fry9 Sept 20043 Sept 202511
Old Windsor Downstream Fry9 Sept 20043 Sept 202513

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

2004–2025

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 1,103 measured fish were spread across different length ranges.

Smallest
1.4 cm
Lower quarter
2.6 cm
Median
3 cm
Upper quarter
3.6 cm
Largest
14.1 cm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the River Old Windsor

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

Dace Gudgeon Chub Roach Minnow 3-spined stickleback

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 →