The Status of Ireland’s Breeding Seabirds: Birds Directive Article 12 Reporting 2013 - 2018

Abstract

Every summer approximately one half to three-quarters of a million seabirds congregate in colonies across Ireland to start their breeding season. Their preferred breeding habitats are principally found on mainland cliffs and on offshore marine islands. These breeding sites are often in close proximity to the rich foraging habitat of continental shelf waters. Ireland is particularly important for its breeding populations of Manx Shearwater, Storm Petrel and Roseate Tern. This Irish Wildlife Manual describes our contemporary knowledge of the twenty-four species of seabirds that regularly breed in Ireland. Data collected under the National Seabird Monitoring Programme over the period 2013 –2018 inclusive allowed for the production of robust contemporary population estimates for the majority of species. The fieldwork to collect such data was accomplished largely by National Parks and Wildlife Service staff and by way of procured contracts to BirdWatch Ireland. This database was further enhanced by the gracious contributions of skilled volunteers.In 2017 the co-ordination and compilation of the data was undertaken by Alan Lauder Consulting under contract to NPWS. Our national species population estimates were compared to those derived from previous surveys over the short-and long-term (usually circa 16 and 32 year periods). Over the short-term it was estimated that 85% of those 20 species assessed were considered to be increasing with only two species (i.e. 10%) showing stable trends and one species (Kittiwake) showing a negative trend since the turn of the century. When this analysis was repeated over the long-term on 19 species approximately 68% were estimated to have increased, 21% decreased and 11% showing morestable trends. With regard to the largely positive trends over the short-and long-term, it is difficult to rule out with precision how much the estimated greater contemporary survey effort,compared to previous surveys,has influenced these assessments but certainly some species have shown spectacular long-term increases (e.g. Roseate Tern, 579%; Common Tern, 201%; Lesser Black-backed Gull, 145%; Gannet,94%; and Fulmar, 68%). Additionally, two seabird species have successfully colonised Ireland since approximately the turn of the century (i.e. Mediterranean Gull and Great Skua). Of the four species that were deemed to have decreased over the long-term (Black-headed Gull, 11%; Common Gull, 25%; Herring Gull, up to 33%; and Kittiwake,35%) only Kittiwake, our most abundant breeding gull species, is also declining over the short-term and thus is of particular cause for concern. Active and targeted conservation work occurs at several tern colonies in Ireland especially along the east and southeast coasts. The analysis set out here shows that effectively managed projects can deliver conservation dividends with strong positive population growth recorded for several tern species at sites including Lady’s Island Lake SPA and Rockabill SPA. These protected site population increases have occurred in concert with decreases in these populations’ breeding ranges at the national level. Thus highlighting the necessity of such interventions. The species assessments set out here in this IWM directly inform Ireland’s reporting on the implementation of EU Birds Directive under Article 12 for the period 2013 –2018 inclusive. Part of this reporting process requires the identification of pressures and threats acting or are likely to act on Ireland’sbreeding seabirds in the coming years. On a per species basis the most frequently identified threats included: off shore wind energy developments; the potential impacts of climate changes on our seabirds foraging habitats; the fishing industry via overfishing or by way of incidental seabird bycatch; mammalian predation; recreational disturbance; and the blight of plastic waste in our oceans whose detrimental impacts on marine life we are now only beginning to quantify in earnest. Further work is required on deriving contemporary population estimates of our burrow nesting seabirds including Puffin, Manx Shearwater and Storm Petrel but historical accounts and the preliminary work thus far has highlighted the acute negative impact that some invasive mammals can have on these breeding species. Eradication projects in tandem with the advancement of biosecurity measures on our most sensitivesites need to be progressed in the near term. The power and efficacy of conservation management can be increasedthrough collaboration. The data collected here through the National Seabird Monitoring Programme is to be combined with the data of our partners and colleagues in the Seabird Monitoring Programme of Britain and Ireland in order to produce an update of the status of Ireland and Britain’s seabird species under the Seabirds Count Project.