Brook lamprey · Lampetra planeri

Brook lamprey in the Knee Brook

Largest measured brook lamprey: 17.5 cm

The largest brook lamprey measured in Environment Agency surveys of the Knee Brook was 17.5 cm, recorded at High Furze on 16 October 1990.

Across 8 measured brook lamprey, the median measured length was 15.2 cm.

RiverFish uses Environment Agency survey measurements rather than rod-and-line angling records. These figures show fish measured during EA surveys of the Knee Brook.

See brook lamprey records across England →

Most recent observation8 September 1999Neighbrook House · 1 fish

Largest measured brook lamprey: 17.5 cm
Median length: 15.2 cm
Fish measured: 8
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
17.5 cm	16 Oct 1990	High Furze	80669
17 cm	17 Oct 1990	Neighbrook House	80686
17 cm	16 Oct 1990	u/s confl Paddle Br Ditchford Frary	80671
15.5 cm	17 Oct 1990	Neighbrook House	80686
15 cm	8 Sept 1999	Neighbrook House	72891
14 cm	8 Sept 1999	u/s & d/s confl. Blockley Brook	72887
11.4 cm	8 Sept 1999	u/s & d/s confl. Blockley Brook	72887
3.3 cm	17 Oct 1990	Neighbrook House	80686

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
u/s & d/s confl. Blockley Brook	8 Sept 1999	8 Sept 1999	1
Neighbrook House	17 Oct 1990	8 Sept 1999	2
u/s confl Paddle Br Ditchford Frary	16 Oct 1990	16 Oct 1990	1
High Furze	16 Oct 1990	16 Oct 1990	1

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

1990–1999

Survey records by year

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

390

091

092

093

094

095

096

097

098

299

Fish measured by surveyors

Measured length distribution

See how the 8 measured fish were spread across different length ranges.

Smallest: 3.3 cm
Lower quarter: 13.4 cm
Median: 15.3 cm
Upper quarter: 17 cm
Largest: 17.5 cm

0–99 mm

100–199 mm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the Knee Brook

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

Brown / sea trout Bullhead Minnow 3-spined stickleback 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 →