Between the 15th and 21st of May 2023 it is Invasive Non-Native Species Week. A wide range of organisations come together during this week, aiming to raise awareness of invasive non-native species (INNS) and the impact they have on people, wildlife, and the environment.
What are INNS?
Invasive non-native species are those which have been introduced into areas outside their natural habitat range through human actions and are posing a threat to native wildlife.
Some of the most common INNS you may have heard of include:
From left to right: Grey squirrel (Sciurus carolinensis), Japanese Knotweed (Reynoutria japonica), and Asian hornet (Vespa velutina)
INNS threaten our native species in a number of ways:
Predation - native species cannot adapt quickly enough to new predators.
Competition for resources – INNS monopolise food, breeding sites, and space forcing out native species.
Disease – native species don’t have the same immunity to new diseases and populations can be decimated.
Hybridisation – when native and non-native species breed, they create hybrids and unique genetic diversity can be lost over time.
Invasive non-native species don’t just threaten biodiversity, they can also damage economic interests such as agriculture, forestry, and fisheries. The estimated cost of dealing with INNS in Britain is several billion pounds annually.
What INNS impact our rivers?
Our rivers are threatened by a number of species including Himalayan balsam (Impatiens glandulifera), North American Signal crayfish (Pacifastacus leniusculus), Floating pennywort (Hydrocotyle ranunculoides) and Prussian carp (Carassius gibelio).
Part of our work at Essex and Suffolk Rivers Trust involves identifying, removing, and preventing the return of invasive species. We have worked on projects involving Himalayan balsam control, and investigating the status of native and non-native crayfish in Essex.
What can you do to help?
There are five simple things that you can do to help prevent the spread of invasive non-native species.
Keep any boats, clothing, footwear and equipment used in water free of invasive non-native species – remember to Check Clean Dry after use.
Be Plant Wise and don't let your garden, pond, or aquarium plants enter the wild.
Take care of your pets, never release them or allow them to escape into the wild. It’s cruel and could harm other wildlife.
Look out for Asian hornet and other alert species and record your sightings.
Volunteer to help control and remove invasive species - keep an eye on our social media pages for INNS volunteer opportunities!