Brook lamprey · Lampetra planeri

Brook lamprey in the River Ouse

Largest measured brook lamprey: 18 cm

The largest brook lamprey measured in Environment Agency surveys of the River Ouse was 18 cm, recorded at Sheffield Bridge on 25 July 2024.

Across 112 measured brook lamprey, the median measured length was 14 cm.

Surveyors recorded weights for 26 brook lamprey. The median was 0.2 oz (0.007 kg) and the largest recorded weight was 0.8 oz (0.022 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 Ouse.

See brook lamprey records across England →

Most recent observation25 July 2024Fletching Mill Upstream · 1 fish

Largest measured brook lamprey: 18 cm
Median length: 14 cm
Fish measured: 112
Survey locations: 8

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 cm	25 Jul 2024	Sheffield Bridge	165939
18 cm	29 Oct 2010	Newick	125033
18 cm	29 Oct 2010	Newick	125033
17.5 cm	25 Jul 2024	Sheffield Bridge	165939
17.5 cm	24 Jul 2024	Sloop	165937
17.5 cm	24 Aug 2006	Sloop	102370
17 cm	29 Oct 2010	Newick	125033
17 cm	25 Aug 2005	Sloop	87584
17 cm	1 Aug 2003	Sloop	76612
16.6 cm	24 Jul 2024	Sloop	165937

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
Sheffield Bridge	13 Aug 2003	25 Jul 2024	6
Fletching Mill Upstream	11 Jul 2011	25 Jul 2024	5
Sloop	13 Aug 2002	24 Jul 2024	10
East Mascalls Bridge	21 Aug 2007	24 Jul 2024	8
Isfield Church	27 Sept 2023	27 Sept 2023	1
Upper Ryelands	19 Nov 2009	1 Oct 2013	2
Newick	9 Oct 2003	18 Jul 2013	3
Sharpsbridge	29 Oct 2009	29 Oct 2009	1

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

2002–2024

Survey records by year

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

102

303

104

105

106

107

108

509

310

111

012

613

014

215

016

417

018

019

020

021

022

223

424

Fish measured by surveyors

Measured length distribution

See how the 112 measured fish were spread across different length ranges.

Smallest: 7 cm
Lower quarter: 13 cm
Median: 14 cm
Upper quarter: 15.5 cm
Largest: 18 cm

0–99 mm

100–199 mm

109

Lengths are direct survey measurements rather than anglers’ catches.

Fish weighed by surveyors

Measured weight summary

Recorded weights were available for 26 brook lamprey. This is a subset of the measured fish and may not represent the whole population.

Lightest: 0.1 oz (0.003 kg)
Lower quarter: 0.2 oz (0.005 kg)
Median: 0.2 oz (0.007 kg)
Upper quarter: 0.3 oz (0.0088 kg)
Heaviest: 0.8 oz (0.022 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 Ouse

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

European eel Perch Roach Dace Gudgeon Stone loach

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 →