RiverFish

Brown / sea trout · Salmo trutta

Brown / sea trout in the River Colne

Largest measured brown / sea trout: 67 cm

The largest brown / sea trout measured in Environment Agency surveys of the River Colne was 67 cm, recorded at Springwell Lane on 20 June 2024.

Across 88 measured brown / sea trout, the median measured length was 27.2 cm.

Surveyors recorded weights for 9 brown / sea trout. The median was 8.5 oz (0.24 kg) and the largest recorded weight was 5 lb 5.7 oz (2.43 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 Colne.

See brown / sea trout records across England →

Most recent observation15 June 2026Springwell Lane · 5 fish
Largest measured brown / sea trout
67 cm
Median length
27.2 cm
Fish measured
88
Survey locations
10

Individual EA measurements

Largest measured brown / sea trout

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

LengthSurvey dateSurvey locationSurvey ID
67 cm20 Jun 2024Springwell Lane165362
65.9 cm12 Jun 2025Springwell Lane176871
62.4 cm19 Feb 1986Denham Court116043
55.7 cm20 Jun 2024Springwell Lane165362
53 cm18 Feb 1986Troy House116046
49.4 cm26 May 2009Springwell Lane117316
48.2 cm12 Jun 2025Springwell Lane176871
48.1 cm19 Jul 2018Denham 2.0152939
42 cm22 Jun 2023Springwell Lane163149
42 cm25 Jun 2008Springwell Lane111527

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

Explore the river

Where brown / sea trout were found

Each point marks a survey location with at least one brown / sea trout 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 brown / sea trout
Springwell Lane18 Oct 200115 Jun 202618
Wall Hall19 May 201120 May 20254
Denham 2.019 Jul 201819 Jul 20181
Drop Lane23 May 201227 May 20152
The Withey Beds20 May 201520 May 20151
Denham5 Oct 20063 Aug 20102
Watford M1 link road25 Jul 200825 Jul 20081
Denham Court19 Feb 198619 Feb 19861
Troy House18 Feb 198618 Feb 19861
Maple Cross12 Feb 198612 Feb 19861

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

1986–2026

Survey records by year

Each bar shows how many survey visits recorded brown / sea trout that year.

Fish measured by surveyors

Measured length distribution

See how the 88 measured fish were spread across different length ranges.

Smallest
5.5 cm
Lower quarter
22.3 cm
Median
27.3 cm
Upper quarter
34.7 cm
Largest
67 cm

Lengths are direct survey measurements rather than anglers’ catches.

Fish weighed by surveyors

Measured weight summary

Recorded weights were available for 9 brown / sea trout. This is a subset of the measured fish and may not represent the whole population.

Lightest
1.3 oz (0.036 kg)
Lower quarter
2.8 oz (0.079 kg)
Median
8.5 oz (0.24 kg)
Upper quarter
2 lb 0.8 oz (0.93 kg)
Heaviest
5 lb 5.7 oz (2.43 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 Colne

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

Chub Perch Roach Pike Dace Gudgeon

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 →