RiverFish

Brook lamprey · Lampetra planeri

Brook lamprey in the River Main Lynher

Largest measured brook lamprey: 15 cm

The largest brook lamprey measured in Environment Agency surveys of the River Main Lynher was 15 cm, recorded at Bicton Bridge on 2 August 2018.

Across 199 measured brook lamprey, the median measured length was 10.2 cm.

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

See brook lamprey records across England →

Most recent observation1 July 2025Knighton · 2 fish
Largest measured brook lamprey
15 cm
Median length
10.2 cm
Fish measured
199
Survey locations
9

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
15 cm2 Aug 2018Bicton Bridge153073
13.6 cm13 Sept 2012Bicton Bridge133500
13.3 cm23 Jun 2011Knighton126644
13.1 cm13 Sept 2018Trebartha153717
13 cm2 Aug 2018Bicton Bridge153073
13 cm13 Sept 2012Bicton Bridge133500
13 cm23 Jun 2011Knighton126644
13 cm8 Aug 2007Knighton106413
12.9 cm12 Sept 2012Plusha Bridge133478
12.8 cm23 Jun 2011Knighton126644

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
Knighton8 Aug 20071 Jul 202512
Rilla Mill12 Sept 201810 Sept 20242
Plusha Bridge12 Sept 20125 Sept 20243
Berriowbridge22 Aug 20063 Sept 20244
Trebartha3 Sept 201229 Aug 20243
Bathpool8 Aug 200727 Aug 20247
Bicton Bridge13 Sept 201222 Aug 20243
Kerney Mill14 Sept 200731 Jul 20249
Pillaton Mill27 Sept 201227 Sept 20121

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

2006–2025

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 199 measured fish were spread across different length ranges.

Smallest
5.4 cm
Lower quarter
8.6 cm
Median
10.2 cm
Upper quarter
11.3 cm
Largest
15 cm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the River Main Lynher

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

Brown / sea trout Bullhead Atlantic salmon European eel Minnow

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 →