Brook lamprey · Lampetra planeri

Brook lamprey in the River Brett (Main Reaches)

Largest measured brook lamprey: 19.3 cm

The largest brook lamprey measured in Environment Agency surveys of the River Brett (Main Reaches) was 19.3 cm, recorded at Higham FGS on 24 April 2018.

Across 18 measured brook lamprey, the median measured length was 17.1 cm.

Surveyors recorded weights for 18 brook lamprey. The median was 0.3 oz (0.009 kg) and the largest recorded weight was 0.6 oz (0.018 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 Brett (Main Reaches).

See brook lamprey records across England →

Most recent observation27 April 2022Higham FGS · 5 fish

Largest measured brook lamprey: 19.3 cm
Median length: 17.1 cm
Fish measured: 18
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
19.3 cm	24 Apr 2018	Higham FGS	152541
18.4 cm	24 Apr 2018	Higham FGS	152541
18.3 cm	24 Apr 2018	Higham FGS	152541
18 cm	27 Apr 2022	Higham FGS	162217
17.9 cm	24 Apr 2018	Higham FGS	152541
17.5 cm	27 Apr 2022	Higham FGS	162217
17.5 cm	22 Apr 2016	Higham FGS	148015
17.3 cm	24 Apr 2018	Higham FGS	152541
17.2 cm	24 Apr 2018	Higham FGS	152541
17.1 cm	24 Apr 2018	Higham FGS	152541

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
Higham FGS	22 Apr 2016	27 Apr 2022	3
Downstream Mill Farm	25 Mar 1982	8 Mar 1985	2

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

1982–2022

Survey records by year

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

182

083

084

185

086

087

088

089

090

091

092

093

094

095

096

097

098

099

000

001

002

003

004

005

006

007

008

009

010

011

012

013

014

015

116

017

118

019

020

021

122

Fish measured by surveyors

Measured length distribution

See how the 18 measured fish were spread across different length ranges.

Smallest: 14.1 cm
Lower quarter: 16.4 cm
Median: 17.2 cm
Upper quarter: 17.8 cm
Largest: 19.3 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 18 brook lamprey. This is a subset of the measured fish and may not represent the whole population.

Lightest: 0.1 oz (0.004 kg)
Lower quarter: 0.3 oz (0.008 kg)
Median: 0.3 oz (0.009 kg)
Upper quarter: 0.4 oz (0.01 kg)
Heaviest: 0.6 oz (0.018 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 Brett (Main Reaches)

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

European eel Pike Roach Gudgeon Dace 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 →