RiverFish

Flounder · Platichthys flesus

Flounder in the Main Avon Sites

Largest measured flounder: 13.5 cm

The largest flounder measured in Environment Agency surveys of the Main Avon Sites was 13.5 cm, recorded at A7R Royalty Gt.Weir to Clay Pool on 1 May 2007.

Across 16 measured flounder, the median measured length was 7 cm.

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

See flounder records across England →

Most recent observation15 August 2024Royalty Downstream Railway Bridge · 2 fish
Largest measured flounder
13.5 cm
Median length
7 cm
Fish measured
16
Survey locations
4

Individual EA measurements

Largest measured flounder

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

LengthSurvey dateSurvey locationSurvey ID
13.5 cm1 May 2007A7R Royalty Gt.Weir to Clay Pool105314
12.2 cm1 May 2007A7R Royalty Gt.Weir to Clay Pool105314
11.4 cm18 May 2005A7R Royalty Gt.Weir to Clay Pool84572
8.4 cm7 Sept 2022Hatchpool at Great Weir162077
8.3 cm7 Sept 2022Hatchpool at Great Weir162077
7.8 cm18 May 2004A7R Royalty Gt.Weir to Clay Pool79874
7.6 cm7 Sept 2022Hatchpool at Great Weir162077
7.1 cm16 Aug 2023Royalty Downstream Railway Bridge164394
7 cm16 Aug 2023Royalty Bottom Island164396
6.9 cm7 Sept 2022Hatchpool at Great Weir162077

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 surveyedFirst recordedLast recordedVisits finding flounder
Royalty Downstream Railway Bridge16 Aug 202315 Aug 20242
Royalty Bottom Island16 Aug 202315 Aug 20242
Hatchpool at Great Weir10 Aug 20047 Sept 20223
A7R Royalty Gt.Weir to Clay Pool18 May 200411 May 20114

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

2004–2024

Survey records by year

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

Fish measured by surveyors

Measured length distribution

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

Smallest
4.9 cm
Lower quarter
5.5 cm
Median
7.1 cm
Upper quarter
8.3 cm
Largest
13.5 cm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the Main Avon Sites

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

Bullhead Minnow Stone loach Brown / sea trout Atlantic salmon 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 →