Dace · Leuciscus leuciscus

Dace in the River Colne

Largest measured dace: 31 cm

The largest dace measured in Environment Agency surveys of the River Colne was 31 cm, recorded at Stanwell Moor on 6 March 1986.

Across 2,768 measured dace, the median measured length was 14.2 cm.

Surveyors recorded weights for 630 dace. The median was 1.6 oz (0.0445 kg) and the largest recorded weight was 1 lb 12.6 oz (0.81 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 Colne.

See dace records across England →

Most recent observation21 July 2026Uxbridge · 4 fish

Largest measured dace: 31 cm
Median length: 14.2 cm
Fish measured: 2,768
Survey locations: 29

Individual EA measurements

Largest measured dace

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
31 cm	6 Mar 1986	Stanwell Moor	116014
28.9 cm	6 Mar 1986	Stanwell Moor	116014
27.2 cm	11 Feb 1986	Springwell Lane	115940
25.9 cm	12 Mar 1986	Moor roundabout 2	116074
25.6 cm	19 Feb 1986	Denham Court	116043
25.5 cm	11 Mar 1986	Staines	116013
25.4 cm	5 Jul 2017	Springwell Lane	150795
25.3 cm	26 Jun 2012	Denham	133912
25.3 cm	12 Mar 1986	Moor roundabout 2	116074
24.7 cm	24 Jul 2018	Springwell Lane	152908

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

Explore the river

Where dace were found

Each point marks a survey location with at least one dace 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 dace
Uxbridge	29 Mar 1999	21 Jul 2026	16
Watford M1 link road	21 Sept 2000	16 Jul 2026	20
Springwell Lane	11 Feb 1986	15 Jun 2026	24
Stanwell Moor	6 Mar 1986	28 May 2026	18
Wall Hall	11 Jul 2003	14 May 2026	21
Drop Lane	8 Jul 2003	23 May 2023	12
Watford Tesco Extra	26 Jul 2022	26 Jul 2022	1
Lairage Land	26 Jul 2022	26 Jul 2022	1
Heathrow EP: Little Britain	31 Oct 2019	31 Oct 2019	1
Heathrow EP: Poyle Channel	28 Oct 2019	28 Oct 2019	1
The Withey Beds	20 May 2015	20 May 2015	1
u/s West Drayton Mill	24 Sept 2013	30 Sept 2014	2
Denham	20 Oct 1998	26 Jun 2012	5
Longbridge Way, Uxbridge	29 May 2012	29 May 2012	1
Elms Lake	19 Feb 2004	19 Feb 2004	1
Harefield Road	17 Jun 1986	17 Jun 1986	1
Old Mill Lane	12 Jun 1986	12 Jun 1986	1
Cricketfield Lane	16 May 1986	16 May 1986	1
Stanwell Road	8 May 1986	8 May 1986	1
Poyle Channel	7 May 1986	7 May 1986	1
Staines Moor	13 Mar 1986	13 Mar 1986	1
Moor roundabout 2	12 Mar 1986	12 Mar 1986	1
Staines	11 Mar 1986	11 Mar 1986	1
Packetboat Lane	27 Feb 1986	27 Feb 1986	1
Uxbridge Moor	26 Feb 1986	26 Feb 1986	1
Milupa Factory	20 Feb 1986	20 Feb 1986	1
Denham Court	19 Feb 1986	19 Feb 1986	1
Maple Cross	12 Feb 1986	12 Feb 1986	1
Mill End	11 Feb 1986	11 Feb 1986	1

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

1986–2026

Survey records by year

Each bar shows how many survey visits recorded dace that year.

1686

087

088

089

090

091

092

093

094

095

096

097

198

199

100

201

202

603

604

605

606

707

608

609

610

311

812

413

314

715

416

417

518

719

020

021

522

423

424

425

526

Fish measured by surveyors

Measured length distribution

See how the 2,768 measured fish were spread across different length ranges.

Smallest: 0.6 cm
Lower quarter: 10.3 cm
Median: 14.2 cm
Upper quarter: 17.7 cm
Largest: 31 cm

0–99 mm

652

100–199 mm

1810

200–299 mm

305

300–399 mm

Lengths are direct survey measurements rather than anglers’ catches.

Fish weighed by surveyors

Measured weight summary

Recorded weights were available for 630 dace. This is a subset of the measured fish and may not represent the whole population.

Lightest: 0 oz (0.0003 kg)
Lower quarter: 0.7 oz (0.021 kg)
Median: 1.6 oz (0.0445 kg)
Upper quarter: 3.4 oz (0.097 kg)
Heaviest: 1 lb 12.6 oz (0.81 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 Colne

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

Chub Perch Roach Pike Gudgeon Bullhead

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 →