Brook lamprey · Lampetra planeri

Brook lamprey in the Tadburn Lake

Largest measured brook lamprey: 18.5 cm

The largest brook lamprey measured in Environment Agency surveys of the Tadburn Lake was 18.5 cm, recorded at Crampmoor Ford on 20 July 2018.

Across 39 measured brook lamprey, the median measured length was 15.5 cm.

Surveyors recorded weights for 2 brook lamprey. The median was 0.3 oz (0.0095 kg) and the largest recorded weight was 0.4 oz (0.01 kg).

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

See brook lamprey records across England →

Most recent observation18 September 2025Crampmoor Ford · 17 fish

Largest measured brook lamprey: 18.5 cm
Median length: 15.5 cm
Fish measured: 39
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.

Length	Survey date	Survey location	Survey ID
18.5 cm	20 Jul 2018	Crampmoor Ford	153119
17.2 cm	21 Sept 2022	Crampmoor Ford	161554
17 cm	21 Sept 2022	Crampmoor Ford	161554
17 cm	21 Sept 2022	Crampmoor Ford	161554
17 cm	21 Sept 2022	Crampmoor Ford	161554
16.9 cm	12 Aug 2005	Ashdown Way	86394
16.8 cm	21 Sept 2022	Crampmoor Ford	161554
16.8 cm	21 Sept 2022	Crampmoor Ford	161554
16.7 cm	12 Aug 2005	Ashdown Way	86394
16.5 cm	21 Sept 2022	Crampmoor Ford	161554

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 surveyed	First recorded	Last recorded	Visits finding brook lamprey
Crampmoor Ford	3 Apr 2012	18 Sept 2025	9
Ashdown Way	12 Aug 2005	9 Sept 2025	8

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.

105

006

007

008

009

010

011

112

013

014

015

016

017

218

219

220

221

222

223

124

225

Fish measured by surveyors

Measured length distribution

See how the 39 measured fish were spread across different length ranges.

Smallest: 11 cm
Lower quarter: 14.3 cm
Median: 15.5 cm
Upper quarter: 16.5 cm
Largest: 18.5 cm

100–199 mm

Lengths are direct survey measurements rather than anglers’ catches.

Fish weighed by surveyors

Measured weight summary

Recorded weights were available for 2 brook lamprey. This is a subset of the measured fish and may not represent the whole population.

Lightest: 0.3 oz (0.009 kg)
Lower quarter: 0.3 oz (0.0092 kg)
Median: 0.3 oz (0.0095 kg)
Upper quarter: 0.3 oz (0.0098 kg)
Heaviest: 0.4 oz (0.01 kg)

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

More fish in this river

Explore the Tadburn Lake

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

Brown / sea trout Bullhead Stone loach 3-spined stickleback European eel Topmouth 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 →