Historic monitoring evidence · Environment Agency
Amwell Loop
Hertfordshire and North London · survey site
This page records ecological survey evidence. It is not proof of current fish presence, abundance, fishing quality, access, permission or safety at this location.
Observed taxa
What monitoring recorded here
Taxa are ordered by latest survey date. Counts and records reflect monitoring events, not an angling forecast.
Chub
Leuciscus cephalus- First record
- 12 Apr 1978
- Latest record
- 15 Jul 2025
- Survey events
- 21
Perch
Perca fluviatilis- First record
- 12 Apr 1978
- Latest record
- 15 Jul 2025
- Survey events
- 20
Dace
Leuciscus leuciscus- First record
- 12 Apr 1978
- Latest record
- 15 Jul 2025
- Survey events
- 19
Bullhead
Cottus gobio- First record
- 12 Apr 1978
- Latest record
- 15 Jul 2025
- Survey events
- 19
Minnow
Phoxinus phoxinus- First record
- 12 Apr 1978
- Latest record
- 15 Jul 2025
- Survey events
- 19
Roach
Rutilus rutilus- First record
- 12 Apr 1978
- Latest record
- 15 Jul 2025
- Survey events
- 17
Gudgeon
Gobio gobio- First record
- 12 Apr 1978
- Latest record
- 15 Jul 2025
- Survey events
- 16
Stone loach
Barbatula barbatula- First record
- 12 Apr 1978
- Latest record
- 15 Jul 2025
- Survey events
- 16
Pike
Esox lucius- First record
- 11 Oct 2002
- Latest record
- 15 Jul 2025
- Survey events
- 15
Brown / sea trout
Salmo trutta- First record
- 19 Sept 2003
- Latest record
- 15 Jul 2025
- Survey events
- 10
Grayling
Thymallus thymallus- First record
- 19 Sept 2003
- Latest record
- 15 Jul 2025
- Survey events
- 3
Tench
Tinca tinca- First record
- 13 Jul 2018
- Latest record
- 15 Jul 2025
- Survey events
- 2
Rainbow trout
Oncorhynchus mykiss- First record
- 6 Jul 2023
- Latest record
- 25 Jun 2024
- Survey events
- 2
Lamprey sp. > ammocoete
Petromyzontidae- First record
- 16 Aug 2007
- Latest record
- 27 Jul 2022
- Survey events
- 3
Ruffe
Gymnocephalus cernuus- First record
- 27 Jul 2022
- Latest record
- 27 Jul 2022
- Survey events
- 1
Brook lamprey
Lampetra planeri- First record
- 11 Oct 2002
- Latest record
- 10 Jul 2017
- Survey events
- 6
Bleak
Alburnus alburnus- First record
- 12 Apr 1978
- Latest record
- 5 Jul 2016
- Survey events
- 9
Pike varieties
Esox lucius- First record
- 12 Apr 1978
- Latest record
- 14 Jul 2010
- Survey events
- 5
Lamprey sp.
Petromyzontidae- First record
- 26 Aug 2005
- Latest record
- 15 Jul 2009
- Survey events
- 2
3-spined stickleback
Gasterosteus aculeatus- First record
- 12 Apr 1978
- Latest record
- 10 Sept 2008
- Survey events
- 6
Brook lamprey > ammocoete
Lampetra planeri- First record
- 22 Sept 2004
- Latest record
- 17 Jul 2007
- Survey events
- 2
Common bream
Abramis brama- First record
- 22 Sept 2004
- Latest record
- 11 Aug 2006
- Survey events
- 3
Brook lamprey ammocoetes
Lampetra planeri- First record
- 19 Sept 2003
- Latest record
- 22 Sept 2004
- Survey events
- 2
Tench varieties
Tinca tinca- First record
- 12 Apr 1978
- Latest record
- 12 Apr 1978
- Survey events
- 1
Rules and access
Check before you travel.
Environment Agency ecology records do not carry fishing-rights boundaries or live restrictions. Confirm the fishery owner, permission, local byelaws, seasonal rules, safety notices and current conditions before setting out.
Check live freshwater fishing rulesProvenance
Source, licence and boundary
- SourceEnvironment Agency Ecology & Fish Data
- LicenceOpen Government Licence v3.0
- Source copy retrieved23 Jul 2026
- Terms checked23 Jul 2026
- CoverageHistoric monitoring evidence, separately dated per record
- Not assertedCurrent presence, access, permission, fishing quality or safety