RiverFish

Brook lamprey · Lampetra planeri

Brook lamprey in the Bucklesham Mill River

Largest measured brook lamprey: 17 cm

The largest brook lamprey measured in Environment Agency surveys of the Bucklesham Mill River was 17 cm, recorded at Water Works Bend (Mill River) on 18 May 2004.

Across 303 measured brook lamprey, the median measured length was 11.7 cm.

Surveyors recorded weights for 240 brook lamprey. The median was 0.1 oz (0.0021 kg) and the largest recorded weight was 0.3 oz (0.0072 kg).

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

See brook lamprey records across England →

Most recent observation24 May 2022Dairy Farm (Mill River) · 89 fish
Largest measured brook lamprey
17 cm
Median length
11.7 cm
Fish measured
303
Survey locations
2

Individual EA measurements

Largest measured brook lamprey

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

LengthSurvey dateSurvey locationSurvey ID
17 cm18 May 2004Water Works Bend (Mill River)84174
16.9 cm18 May 2004Water Works Bend (Mill River)84174
16.3 cm18 May 2004Water Works Bend (Mill River)84174
16 cm18 May 2004Water Works Bend (Mill River)84174
15.9 cm24 May 2010Dairy Farm (Mill River)121727
15.7 cm24 May 2022Dairy Farm (Mill River)162216
15.5 cm24 May 2022Dairy Farm (Mill River)162216
15.5 cm24 May 2022Dairy Farm (Mill River)162216
15.5 cm19 May 2004Dairy Farm (Mill River)84166
15.1 cm24 May 2022Dairy Farm (Mill River)162216

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

Explore the river

Where brook lamprey were found

Each point marks a survey location with at least one brook lamprey 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 brook lamprey
Dairy Farm (Mill River)18 May 198924 May 20227
Water Works Bend (Mill River)3 Mar 199327 May 20165

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

1989–2022

Survey records by year

Each bar shows how many survey visits recorded brook lamprey that year.

Fish measured by surveyors

Measured length distribution

See how the 303 measured fish were spread across different length ranges.

Smallest
4 cm
Lower quarter
9.7 cm
Median
11.7 cm
Upper quarter
13 cm
Largest
17 cm

Lengths are direct survey measurements rather than anglers’ catches.

Fish weighed by surveyors

Measured weight summary

Recorded weights were available for 240 brook lamprey. This is a subset of the measured fish and may not represent the whole population.

Lightest
0 oz (0.0001 kg)
Lower quarter
0 oz (0.0013 kg)
Median
0.1 oz (0.0021 kg)
Upper quarter
0.1 oz (0.0032 kg)
Heaviest
0.3 oz (0.0072 kg)

These are direct individual weights recorded by Environment Agency surveyors. Combined bulk weights are not included.

More fish in this river

Explore the Bucklesham Mill River

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

Brown / sea trout European eel 3-spined stickleback Flounder Perch

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 →