A Widely Spread Species is a species that is on the Species of Union Concern list and is considered established and widely spread in Northern Ireland.
Article 19 of EU Regulation (1143/2014) requires Member States to produce effective management measures for each of the selected Widely Spread Species. These measures will endeavour to minimise the potential negative impact upon biodiversity, related ecosystem services, human health and the economy that these 11 species could have.
The 11 Widely Spread Species in Northern Ireland and their associated management measures are listed below, they consist of 8 plants and 3 animals.
| Animals | |
| New Zealand Flatworm (Arthurdendyus triangulatus) |
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| Grey squirrel (Sciurus carolinensis) |
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| Slider terrapins (Trachemys scripta spp.) |
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