RiverFish

River lamprey · Lampetra fluviatilis

River lamprey in the River Derwent

Largest measured river lamprey: 18.5 cm

The largest river lamprey measured in Environment Agency surveys of the River Derwent was 18.5 cm, recorded at River Derwent at Shotley Bridge on 31 July 2013.

Across 15 measured river lamprey, the median measured length was 13 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 Derwent.

See river lamprey records across England →

Most recent observation31 July 2013River Derwent at Shotley Bridge · 4 fish
Largest measured river lamprey
18.5 cm
Median length
13 cm
Fish measured
15
Survey locations
3

Individual EA measurements

Largest measured river lamprey

The largest individual measurements in this river and species dataset. Equal measurements are retained as separate surveyed fish.

LengthSurvey dateSurvey locationSurvey ID
18.5 cm31 Jul 2013River Derwent at Shotley Bridge137577
16.8 cm13 Sept 2009River Derwent at Eddy's Bridge119120
16.1 cm31 Jul 2013River Derwent at Shotley Bridge137577
14 cm31 Jul 2013River Derwent at Shotley Bridge137577
14 cm13 Sept 2009River Derwent at Eddy's Bridge119120
13.5 cm9 Oct 2012River Derwent at Eddy's Bridge134855
13 cm31 Jul 2013River Derwent at Shotley Bridge137577
13 cm9 Oct 2012River Derwent at Eddy's Bridge134855
12.8 cm9 Aug 2009River Derwent at Allensford120337
12.5 cm9 Oct 2012River Derwent at Eddy's Bridge134855

Lengths are direct survey measurements. RiverFish does not estimate fish weights from length.

Explore the river

Where river lamprey were found

Each point marks a survey location with at least one river 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 river lamprey
River Derwent at Shotley Bridge31 Jul 201331 Jul 20131
River Derwent at Eddy's Bridge13 Sept 200930 Jul 20133
River Derwent at Allensford9 Aug 20099 Aug 20091

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

2009–2013

Survey records by year

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

Fish measured by surveyors

Measured length distribution

See how the 15 measured fish were spread across different length ranges.

Smallest
6 cm
Lower quarter
11.3 cm
Median
13 cm
Upper quarter
14 cm
Largest
18.5 cm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the River Derwent

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

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

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 →