Brook lamprey · Lampetra planeri

Brook lamprey in the River Glen Downstream Confluence

Largest measured brook lamprey: 14.4 cm

The largest brook lamprey measured in Environment Agency surveys of the River Glen Downstream Confluence was 14.4 cm, recorded at Upstream Kates Bridge on 3 September 2024.

Across 5 measured brook lamprey, the median measured length was 13.2 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 Glen Downstream Confluence.

See brook lamprey records across England →

Most recent observation28 October 2025Downstream Kates Bridge · 1 fish

Largest measured brook lamprey: 14.4 cm
Median length: 13.2 cm
Fish measured: 5
Survey locations: 4

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
14.4 cm	3 Sept 2024	Upstream Kates Bridge	167151
13.7 cm	3 Sept 2024	Upstream Kates Bridge	167151
13.2 cm	3 Sept 2024	Upstream Kates Bridge	167151
12.7 cm	28 Oct 2025	Downstream Kates Bridge	179993
12 cm	7 Jul 2005	Downstream Kates Bridge	86220

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
Downstream Kates Bridge	7 Jul 2005	28 Oct 2025	5
Upstream Kates Bridge	5 May 2010	3 Sept 2024	2
Downstream Fletland Mill	23 Mar 2016	23 Mar 2016	1
Wilsthorpe	16 Oct 2006	13 Aug 2009	2

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

206

107

008

109

110

011

012

013

014

015

116

117

018

019

020

021

022

023

124

125

Fish measured by surveyors

Measured length distribution

See how the 5 measured fish were spread across different length ranges.

Smallest: 12 cm
Lower quarter: 12.7 cm
Median: 13.2 cm
Upper quarter: 13.7 cm
Largest: 14.4 cm

100–199 mm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the River Glen Downstream Confluence

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

Pike European eel Minnow Bullhead Chub Dace

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 →