Brook lamprey · Lampetra planeri

Brook lamprey in the River Arrow

Largest measured brook lamprey: 15 cm

The largest brook lamprey measured in Environment Agency surveys of the River Arrow was 15 cm, recorded at The Forge on 12 August 2024.

Across 9 measured brook lamprey, the median measured length was 12.7 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 Arrow.

See brook lamprey records across England →

Most recent observation12 August 2024The Forge · 2 fish

Largest measured brook lamprey: 15 cm
Median length: 12.7 cm
Fish measured: 9
Survey locations: 6

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
15 cm	12 Aug 2024	The Forge	166330
13.5 cm	12 Aug 2024	The Forge	166330
13.1 cm	24 Jul 2019	Ivington	154976
12.8 cm	24 Jul 2019	Ivington	154976
12.7 cm	24 Jul 2019	Ivington	154976
11 cm	24 Jul 2019	Ivington	154976
10 cm	24 Jul 2019	Ivington	154976
9.5 cm	24 Jul 2019	Ivington	154976
7.4 cm	24 Jul 2019	Ivington	154976

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
The Forge	12 Aug 2024	12 Aug 2024	1
Ivington	24 Jul 2019	24 Jul 2019	1
W053p	18 Sept 2006	18 Sept 2006	1
Monkland	28 Jul 2004	28 Jul 2004	1
W017	4 Aug 1994	4 Aug 1994	1
Pembridge	28 Jul 1989	28 Jul 1989	1

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

1989–2024

Survey records by year

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

189

090

091

092

093

194

095

096

097

098

099

000

001

002

003

104

005

106

007

008

009

010

011

012

013

014

015

016

017

018

119

020

021

022

023

124

Fish measured by surveyors

Measured length distribution

See how the 9 measured fish were spread across different length ranges.

Smallest: 7.4 cm
Lower quarter: 10 cm
Median: 12.7 cm
Upper quarter: 13.1 cm
Largest: 15 cm

0–99 mm

100–199 mm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the River Arrow

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

Brown / sea trout Bullhead Minnow Stone loach Atlantic salmon European eel

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 →