INVASIVE SPECIES/BIOSECURITY

For many years now the Eden catchment has suffered from the effects of himalayan balsam, and in some areas Japanese knot weed. These species of invasive plants cause a great deal of damage to the riverbanks by leaving them devoid of any vegetation throughout the winter months; which ultimately results in erosion of the banks when flooding occurs.
The initial rapid spread of these invasive plants was uncontrolled, and by the time we realised the problems they were causing, it was too vast a job to be able to eradicate them. In reflection we might not have been able to fully wipe out these invasive plans, but with a little effort we may well have kept them under control.

We all hoped that no other invasive species would reach the Eden system, however, very little was done to prevent this happening, then in 2013 the Signal crayfish, another invasive species, was identified in one of the tributaries of the lower R.Eden. We need now to make sure that this species does not spread into the whole system.

We are also aware of two other invasive species, the Killer shrimp, Dikerogammarus villosus and the Daemon shrimp Dikerogammarus haemobaphes which have been identified in certain parts of the country, in 2010 and in 2012 respectively. Dikerogammarus villosus is particularly voracious and an aggressive predator which preys on a range of invertebrates and young fish, sometimes causing their extinction. It tends to dominate its habitat, killing and maiming unselectively. In rivers in other parts of the world it has been damaging to smaller species and ruined ecological chains.

Once established, invasive species are extremely difficult and costly to eradicate. Prevention and early intervention are far more successful and cost-effective.

We therefore ask you to help ‘Stop the Spread’ of these invasive species by cleaning and drying your fishing tackle, such as waders, wading boots and landing nets before every outing to the Associations waters.

Alternatively, if you cannot get your gear dry for a long enough period before your next outing, soak them in water that is around 45 degree centigrade, or just slightly above this temperature, for several minutes. You can also check out the link below….

NNSS – Non-Native Species Secretariat