RiverFish

3-spined stickleback · Gasterosteus aculeatus

3-spined stickleback in the River Medway

Largest measured 3-spined stickleback: 10.7 cm

The largest 3-spined stickleback measured in Environment Agency surveys of the River Medway was 10.7 cm, recorded at Hartfield on 29 May 2007.

Across 54 measured 3-spined stickleback, the median measured length was 3 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 Medway.

See 3-spined stickleback records across England →

Most recent observation28 May 2025Tonbridge Juvenile Fish Seine Netting Survey · 1 fish
Largest measured 3-spined stickleback
10.7 cm
Median length
3 cm
Fish measured
54
Survey locations
9

Individual EA measurements

Largest measured 3-spined stickleback

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

LengthSurvey dateSurvey locationSurvey ID
10.7 cm29 May 2007Hartfield106462
10.5 cm29 May 2007Hartfield106462
7.9 cm29 May 2007Hartfield106462
6.8 cm29 May 2007Hartfield106462
5.2 cm21 Jun 2013Tonbridge Juvenile Fish Seine Netting Survey138065
4.5 cm3 Sept 2014Penshurst142593
4.4 cm28 May 2025Tonbridge Juvenile Fish Seine Netting Survey177057
3.8 cm15 Aug 2012Hartfield132882
3.8 cm14 Nov 2001Fordcombe22486
3.7 cm1 Sept 2016Hartfield149137

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

Explore the river

Where 3-spined stickleback were found

Each point marks a survey location with at least one 3-spined stickleback 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 3-spined stickleback
Tonbridge Juvenile Fish Seine Netting Survey30 Aug 201228 May 20255
Maidstone Juvenile Fish Seine Netting Survey2 Jul 201514 Jul 20234
Tonbridge Juvenile Fish Kick Sampling Survey20 Jul 201228 Jul 20175
D/s Ashurst Road Bridge15 Jul 200513 Sept 20162
Hartfield29 May 20071 Sept 20164
Maidstone Juvenile Fish Kick Sampling Survey8 Aug 20168 Aug 20161
Penshurst3 Sept 20143 Sept 20141
Fordcombe14 Nov 200125 Sept 20132
Sovereign Way Tonbridge11 Sept 201311 Sept 20131

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

2001–2025

Survey records by year

Each bar shows how many survey visits recorded 3-spined stickleback that year.

Fish measured by surveyors

Measured length distribution

See how the 54 measured fish were spread across different length ranges.

Smallest
1.6 cm
Lower quarter
2.6 cm
Median
3 cm
Upper quarter
3.4 cm
Largest
10.7 cm

Lengths are direct survey measurements rather than anglers’ catches.

More fish in this river

Explore the River Medway

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

Chub Gudgeon Roach Perch Bleak 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 →