Historic monitoring evidence · Environment Agency
River Aln at Bolton Mill
North East · 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.
Brown / sea trout
Salmo trutta- First record
- 23 Sept 1993
- Latest record
- 23 Jun 2026
- Survey events
- 23
Atlantic salmon
Salmo salar- First record
- 28 Sept 1995
- Latest record
- 23 Jun 2026
- Survey events
- 21
Stone loach
Barbatula barbatula- First record
- 23 Sept 1993
- Latest record
- 23 Jun 2026
- Survey events
- 20
Minnow
Phoxinus phoxinus- First record
- 23 Sept 1993
- Latest record
- 23 Jun 2026
- Survey events
- 19
3-spined stickleback
Gasterosteus aculeatus- First record
- 23 Sept 1993
- Latest record
- 23 Jun 2026
- Survey events
- 16
European eels > elvers
Anguilla anguilla- First record
- 8 Aug 2001
- Latest record
- 23 Jun 2026
- Survey events
- 8
Lampetra sp.
Lampetra- First record
- 19 Jul 2010
- Latest record
- 23 Jun 2026
- Survey events
- 2
Lamprey sp.
Petromyzontidae- First record
- 23 Sept 1993
- Latest record
- 17 Jun 2025
- Survey events
- 12
European eel
Anguilla anguilla- First record
- 23 Sept 1993
- Latest record
- 17 Jun 2025
- Survey events
- 8
River lamprey > ammocoete
Lampetra fluviatilis- First record
- 27 Jul 2009
- Latest record
- 1 Jul 2013
- Survey events
- 2
River lamprey
Lampetra fluviatilis- First record
- 17 Sept 2012
- Latest record
- 17 Sept 2012
- 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