Horizon scan of invasive alien species for the island of Ireland

Frances E. Lucy*, Eithne Davis, Roy Anderson, Olaf Booy, Ken Bradley, J. Robert Britton, Colin Byrne, Joseph M. Caffrey, Neil E. Coughlan, Kate Crane, Ross N. Cuthbert, Jaimie T.A. Dick, James W.E. Dickey, Jeffrey Fisher, Cathal Gallagher, Simon Harrison, Matthew Jebb, Mark Johnson, Colin Lawton, Dave LyonsTim Mackie, Christine Maggs, Ferdia Marnell, Tom McLoughlin, Dan Minchin, Oonagh Monaghan, Ian Montgomery, Niall Moore, Liam Morrison, Rose Muir, Brian Nelson, Art Niven, Colette O’Flynn, Bruce Osborne, Ruth M. O’Riordan, Neil Reid, Helen Roy, Rory Sheehan, Dorothy Stewart, Monica Sullivan, Paula Tierney, Paula Treacy, Elena Tricarico, Wayne Trodd

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)
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Ireland, being an island situated on Europe’s western seaboard, has a fewer number of native species than mainland European Union Member States (MS). Increased numbers of vectors and pathways have reduced the island’s biotic isolation, increasing the risk of new introductions and their associated impacts on native biodiversity. It is likely that these risks are greater here than they are in continental MSs, where the native biodiversity is richer. A horizon scanning approach was used to identify the most likely invasive alien species (IAS) (with the potential to impact biodiversity) to arrive on the island of Ireland within the next ten years. To achieve this, we used a consensus-based approach, whereby expert opinion and discussion groups were utilised to establish and rank a list of 40 species of the most likely terrestrial, freshwater and marine IAS to arrive on the island of Ireland within the decade 2017–2027. The list of 40 included 18 freshwater, 15 terrestrial and seven marine IAS. Crustacean species (freshwater and marine) were taxonomically dominant (11 out of 40); this reflects their multiple pathways of introduction, their ability to act as ecosystem engineers and their resulting high impacts on biodiversity. Freshwater species dominated the top ten IAS (seven species out of ten), with the signal crayfish (Pacifastacus leniusculus) highlighted as the most likely species to arrive and establish in freshwaters, while roe deer (Capreolus capreolus) (second) and the warm-water barnacle (Hesperibalanus fallax) (fifth), were the most likely terrestrial and marine invaders. This evidence-based list provides important information to the relevant statutory agencies in both the Republic of Ireland and Northern Ireland to prioritise the prevention of the most likely invaders and aid in compliance with legislation, in particular the EU Regulation on Invasive Alien Species (EU 1143/2014). Targeted biosecurity in both jurisdictions is urgently required in order to manage the pathways and vectors of arrival, and is vital to maintaining native biodiversity on the island of Ireland.

Original languageEnglish
Pages (from-to)155-177
Number of pages23
JournalManagement of Biological Invasions
Issue number2
Publication statusPublished - 27 Apr 2020

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Ecology
  • Management, Monitoring, Policy and Law


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