RiverFish

Brook lamprey · Lampetra planeri

Brook lamprey in the River Anton

Largest measured brook lamprey: 13 cm

The largest brook lamprey measured in Environment Agency surveys of the River Anton was 13 cm, recorded at Rooksbury Mill on 9 September 2010.

Across 10 measured brook lamprey, the median measured length was 9.9 cm.

Surveyors recorded one individual weight: 0.1 oz (0.003 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 Anton.

See brook lamprey records across England →

Most recent observation8 September 2025Cottonworth · 4 fish
Largest measured brook lamprey
13 cm
Median length
9.9 cm
Fish measured
10
Survey locations
3

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
13 cm9 Sept 2010Rooksbury Mill123791
12.5 cm9 Sept 2010Rooksbury Mill123791
12.4 cm1 Sept 2005Artists Way86371
11 cm8 Sept 2025Cottonworth178941
10 cm14 Sept 2023Cottonworth163428
9.8 cm14 Sept 2023Cottonworth163428
7.4 cm14 Sept 2023Cottonworth163428
6.5 cm8 Sept 2025Cottonworth178941
6 cm8 Sept 2025Cottonworth178941
6 cm8 Sept 2025Cottonworth178941

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
Cottonworth14 Sept 20238 Sept 20252
Artists Way1 Sept 20052 May 20132
Rooksbury Mill9 Sept 20109 Sept 20101

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

2005–2025

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 10 measured fish were spread across different length ranges.

Smallest
6 cm
Lower quarter
6.7 cm
Median
9.9 cm
Upper quarter
12.1 cm
Largest
13 cm

Lengths are direct survey measurements rather than anglers’ catches.

Fish weighed by surveyors

Measured weight summary

One individual weight was recorded for this fish and river. This is a subset of the measured fish and may not represent the whole population.

Recorded weight
0.1 oz (0.003 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 Anton

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

Brown / sea trout Bullhead Grayling European eel 3-spined stickleback Pike

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 →