Flounder · Platichthys flesus

Flounder in the River Holbrook

Largest measured flounder: 32.9 cm

The largest flounder measured in Environment Agency surveys of the River Holbrook was 32.9 cm, recorded at Holbrook Sluice on 24 January 1991.

Across 69 measured flounder, the median measured length was 9.8 cm.

Surveyors recorded weights for 46 flounder. The median was 0.4 oz (0.01 kg) and the largest recorded weight was 12.3 oz (0.35 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 Holbrook.

See flounder records across England →

Most recent observation25 June 2003Holbrook Sluice · 16 fish

Largest measured flounder: 32.9 cm
Median length: 9.8 cm
Fish measured: 69
Survey locations: 1

Individual EA measurements

Largest measured flounder

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
32.9 cm	24 Jan 1991	Holbrook Sluice	14734
32.5 cm	10 Dec 1999	Holbrook Sluice	14737
32.2 cm	25 Jun 2003	Holbrook Sluice	79275
26.2 cm	25 Jun 2003	Holbrook Sluice	79275
25.2 cm	25 Jun 2003	Holbrook Sluice	79275
24.6 cm	25 Jun 2003	Holbrook Sluice	79275
24.2 cm	25 Jun 2003	Holbrook Sluice	79275
23 cm	25 Jun 2003	Holbrook Sluice	79275
21.2 cm	10 Dec 1999	Holbrook Sluice	14737
20.2 cm	25 Jun 2003	Holbrook Sluice	79275

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

Explore the river

Where flounder were found

Each point marks a survey location with at least one flounder 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 flounder
Holbrook Sluice	1 Dec 1987	25 Jun 2003	5

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

1987–2003

Survey records by year

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

187

088

089

090

191

092

193

094

095

096

097

098

199

000

001

002

103

Fish measured by surveyors

Measured length distribution

See how the 69 measured fish were spread across different length ranges.

Smallest: 5 cm
Lower quarter: 7.9 cm
Median: 9.8 cm
Upper quarter: 14.5 cm
Largest: 32.9 cm

0–99 mm

100–199 mm

200–299 mm

300–399 mm

Lengths are direct survey measurements rather than anglers’ catches.

Fish weighed by surveyors

Measured weight summary

Recorded weights were available for 46 flounder. This is a subset of the measured fish and may not represent the whole population.

Lightest: 0.4 oz (0.01 kg)
Lower quarter: 0.4 oz (0.01 kg)
Median: 0.4 oz (0.01 kg)
Upper quarter: 0.4 oz (0.01 kg)
Heaviest: 12.3 oz (0.35 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 Holbrook

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

European eel

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 →