RiverFish

Brook lamprey · Lampetra planeri

Brook lamprey in the River Main Fowey

Largest measured brook lamprey: 14.1 cm

The largest brook lamprey measured in Environment Agency surveys of the River Main Fowey was 14.1 cm, recorded at Ashford Bridge on 6 September 2016.

Across 190 measured brook lamprey, the median measured length was 10.9 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 Fowey.

See brook lamprey records across England →

Most recent observation19 September 2024Ashford Bridge · 4 fish
Largest measured brook lamprey
14.1 cm
Median length
10.9 cm
Fish measured
190
Survey locations
5

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
14.1 cm6 Sept 2016Ashford Bridge149334
14 cm10 Aug 2022Upstream Doublebois Bridge161620
14 cm1 Sept 2021Upstream Doublebois Bridge160534
13.8 cm1 Sept 2011Respryn Bridge127651
13.6 cm6 Aug 2024Upstream Doublebois Bridge166928
13.5 cm6 Sept 2019Halfway155681
13.5 cm16 Sept 2012Doublebois133745
13.3 cm6 Aug 2024Upstream Doublebois Bridge166928
13.3 cm6 Aug 2024Upstream Doublebois Bridge166928
13.1 cm16 Sept 2012Doublebois133745

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
Ashford Bridge20 Sept 201219 Sept 20246
Halfway31 Aug 201815 Aug 20243
Upstream Doublebois Bridge13 Sept 20166 Aug 20245
Doublebois22 Aug 200621 Aug 20144
Respryn Bridge1 Sept 20111 Sept 20111

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

2006–2024

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 190 measured fish were spread across different length ranges.

Smallest
5.6 cm
Lower quarter
9.9 cm
Median
10.9 cm
Upper quarter
12 cm
Largest
14.1 cm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the River Main Fowey

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

Brown / sea trout Bullhead European eel Atlantic salmon Minnow 3-spined stickleback

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 →