New threats to our rivers

All river users benefit from a healthy aquatic environment. Anglers and other river users need to be aware of the dangers that they might inadvertently pose to indigenous flora and fauna, and what they should do about it.

Clothing and equipment (especially nets and waders) that have not been thoroughly dried or disinfected can carry parasites and other diseases and infect water bodies. These can have devastating effects as species that inhabit the newly infected water body have little or no immunity. Crayfish plague is just such a disease. It is carried by the American signal crayfish, which is widely prevalent and immune to the parasite whereas our native white clawed crayfish is not.

Another potentially damaging plague is Gyrodactylus salaris (GS) which affects salmon and this could and be brought in from the continent. It has devastated rivers in Norway.

A more recent threat has come from the killer shrimp Dikerogammarus villosus, a destructive species that has arrived in UK waters from Eastern Europe. If introduced into new rivers they too will have a devastating effect on native species of invertebrates, fish and other wildlife. For more information on killer shrimp please click here. Or see:

The risk of crayfish plague, GS and killer shrimp require precautions to be taken.

What You Must Do

Certain items of your clothing and equipment (especially nets, felt soles and waders) can be very effective means by which you could infect water. In addition to abiding by any rules restricting the use of keepnets, if your equipment or clothing has been used abroad or on any different UK river or still water in the 7 days prior to your fishing (or any tributary), you must ensure that it has been properly sterilized through one of the following methods before you arrive:

  • Method A: Drying to a minimum of 20 deg C for at least 2 days.
  • Method B: Heating to above 60 deg C for at least one hour.
  • Method C: Deep freezing for at least one day.