Narrow-clawed crayfish
Pontastacus leptodactylus
Status:
Potential
Habitat:
Freshwater
Threats:
Can impact habitat structure and outcompete native crayfish
New Guinea flatworm
Platydemus manokwari
Status:
Potential
Habitat:
Terrestrial
Threats:
Can cause declines of native snail species, with cascading impacts on food webs, decomposition, and nutrient cycling.
Noble crayfish
Astacus astacus
Status:
Potential
Habitat:
Freshwater
Threats:
Negatively impact habitat structure with burrows, reduce native species, competition with native crayfish
North American Beaver
Castor canadensis
Status:
Potential
Habitat:
Terrestrial
Threats:
Drastically reshape ecosystems by altering water flow, vegetation, and chemistry, which can increase flooding and productivity.
North American signal crayfish
Pacifastacus leniusculus
Status:
Potential
Habitat:
Freshwater
Threats:
Detrimental impacts on white clawed crayfish. Human health impacts.
Northern giant hornet
Vespa mandarinia
Status:
Potential
Habitat:
Terrestrial
Threats:
Canrapidly destroy beehives, poses a serious human health risk through painful and potentially lethal stings.
Northern Pacific seastar
Asterias amurensis
Status:
Potential
Habitat:
Marine
Threats:
Causes major ecological and economical damage by preying heavily on native and farmed bivalves.
Northern Snakehead
Channa argus
Status:
Potential
Habitat:
Freshwater
Threats:
Predation of native fish stocks, vector for disease and parasites
Northern weatherfish
Misgurnus bipartitus
Status:
Potential
Habitat:
Freshwater
Threats:
The species threatens native wetland fish by spreading quickly and outcompeting them for food and habitat.

Invasive Species Northern Ireland