Freshwater Invasive Non-Native Species (INNS)

Invasive non-native species also pose a major threat to freshwater habitats and species on the Isle of Man, e.g. by outcompeting native species, spreading diseases or altering aquatic habitats. Their introduction could also have severe economic consequences via closure or reducing the quality of fisheries or damaging infrastructure. Some of these organisms can live for many days on damp surfaces or in crevices, or in the bilges and hatches of boats, and so anglers and water sports enthusiasts are urged to follow the ‘Check, Clean, Dry’ procedure to minimise the risk of transferring INNS to the island and to reduce the spread of those that are already present. This procedure can be found in the following leaflets along with further details on some of the invasive species that could cause problems in our inland waters:

Biosecurity Recreational Anglers

Biosecurity Recreational Boats and equipment

Some non-native terrestrial plants, such as Japanese knotweed and Himalayan balsam, can easily become dominant along river banks causing issues for the aquatic environment e.g. by accelerating bank erosion or hampering habitat management and maintenance of infrastructure. For further information and advice on control measures of terrestrial plants, see the Terrestrial INNS page

Contact Details (Freshwater INNS)

DEFA (Inland Fisheries)

Telephone: +44 1624 685857
Email: fisheries@gov.im

Manx Wildlife Trust (Marine and Freshwater Officer)

Telephone: +44 1624 844432
 Email: enquiries@mwt.im