ARAnglerRadar evidence & rules

Hertfordshire and North London · Environment Agency surveys

What fish are in the Alleviation of Low Flow (ALF) study?

Monitoring has recorded 11 species across 4 surveyed sites on this water, between 1999 and 2000. These are survey records with dates. They do not establish what is present today, that the water is fishable, or that you have permission to fish it.

Recorded species

What monitoring has found here

Ordered by how many sites on this water recorded the species. A species not listed has not been recorded by these surveys — which is not the same as being absent.

  1. 3-spined sticklebackGasterosteus aculeatus3 siteslatest 7 Nov 2000
  2. BullheadCottus gobio3 siteslatest 7 Nov 2000
  3. Stone loachBarbatula barbatula3 siteslatest 7 Nov 2000
  4. Pike varietiesEsox lucius2 siteslatest 27 Jun 2000
  5. 10-spined sticklebackPungitius pungitius1 sitelatest 12 May 1999
  6. ChubLeuciscus cephalus1 sitelatest 7 Nov 2000
  7. DaceLeuciscus leuciscus1 sitelatest 7 Nov 2000
  8. European eelAnguilla anguilla1 sitelatest 27 Jun 2000
  9. MinnowPhoxinus phoxinus1 sitelatest 7 Nov 2000
  10. PerchPerca fluviatilis1 sitelatest 7 Nov 2000
  11. Rainbow troutOncorhynchus mykiss1 sitelatest 14 May 1999

Surveyed sites on this water

4 shown, newest survey first

Provenance

Source and licence

  • SourceEnvironment Agency Ecology & Fish Data
  • LicenceOpen Government Licence v3.0
  • Source copy retrieved23 Jul 2026
  • Waterbody nameAs published by the Environment Agency
  • Not assertedCurrent presence, access, permission, fishing quality or safety
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