The report includes detailed information about the population trends and breeding success of seabirds in Northern Ireland, over the 2023 breeding season. Notably, Fulmar and Kittiwake populations are reported to be experiencing continued declines, while Guillemot, Common Gull and Herring Gull populations show increases at most breeding sites. Low productivity was reported in Black-headed Gulls, Sandwich Terns and Common Terns, likely due to the impacts of highly pathogenic avian influenza (HPAI). Although Black-headed Gulls make up the majority of confirmed HPAI mortality cases in Northern Ireland in 2023, other birds significantly affected include terns, Kittiwakes and auks. A contributor report about HPAI in Northern Ireland by Ronan Owens (Higher Scientific Officer, DAERA, NIEA) details developments in environmental organisations’ responses to HPAI in 2023, including cross-sector communication, improved surveillance and monitoring of HPAI impacts, and improved online systems for the public to report dead birds. Monitoring reports for Strangford Lough and the Outer Ards are included, as well as several additional contributor articles: Copeland gull censuses, by Roisin Kearney (Assistant Conservation Officer, RSPB). The Copeland Islands host one of the largest mixed gull colonies in Northern Ireland, with significant numbers of Lesser Black-backed Gulls and Herring Gulls. The annual gull census was established in 2018; the article details the refinement of the methodology to date as well as the census results so far. Manx Shearwater tracking, by Patrick Lewin (DPhil Student, OxNav, Dept. of Biology, University of Oxford). Tracking the Manx Shearwaters that breed on Lighthouse Island (one of the three Copeland Islands) began in 2007. The article describes the history of tracking Manx Shearwaters from Copeland, including recent advances in technology that have allowed the tracking of fledgling birds as well as adults of breeding age, and the impact of this research on the conservation of shearwaters. Puffin surveys on Rathlin, by Ric Else (Life RAFT Senior Research Assistant, RSPB). Rathlin Island hosts Northern Ireland’s largest seabird colony. The response of seabirds to the removal of introduced Ferrets and Brown Rats from Rathlin is currently being monitored, with a particular focus on Puffins. These birds are especially vulnerable to mammalian predators because of their burrow nests. The article describes the challenges associated with calculating a population estimate, monitoring productivity and mapping the distribution of this species, and how these are being addressed in seabird surveys on Rathlin.

The 10th NI Seabird Report charts the fortunes of Northern Ireland's breeding seabird species and sheds light on the initial impact of avian influenza. The report highlights that Fulmars continue to be at a low ebb in Northern Ireland, with numbers at most sites monitored in 2022 mostly stable or declining slightly. Kittiwake numbers continue to increase at monitored sites, while the numbers of Common Terns appear to have recovered after a bad year in 2020, when the total coastal Northern Irish population (including Belfast Lough RSPB, Carlingford Lough, Cockle Island, Larne Lough and Strangford Lough) more than halved from 2019 levels due to losses at Larne and Belfast Loughs. The report also documents the impacts of highly pathogenic avian influenza on Northern Ireland's seabirds, reveals how detection dogs are being used to monitor burrow-nesting species, explores the foraging behaviour of Black Guillemots, and highlights the monitoring work being done in Strangford Lough.

There was a significant survey effort by volunteers, NGOs and NIEA around Northern Ireland’s coastline for the last year of the Seabirds Count census period, finding that fortunes were mixed for the 20 breeding species of seabird in Northern Ireland. Fulmars continue to decline across most sites, while large gulls buck the national trends and are increasing across Northern Ireland. A team from NIEA found that Fulmar had declined at Downhill (-86%) and Binevenagh (-95%) between the Seabird 2000 census (1998-2002) and the Seabirds Count census (2015-2021), while volunteer-led monitoring of the scattered numbers along the east Co. Antrim coast showed numbers had declined by 73%. However, a rare survey visit to The Skerries by volunteers showed that numbers of Fulmar here had risen by 54% to 43 Apparently Occupied Sites. Large gulls have been increasing at most sites around Northern Ireland, with particularly good annual data collected by the National Trust for Strangford Lough. In 2021, the numbers of Great Black-backed Gulls in the lough were at their highest since 1972, with 143 nests recorded. Black Guillemots are a favourite of seabird monitoring volunteers in Northern Ireland, and we closed the census period with an incredible 80% of sites in NI covered for this species, with those sites left un-surveyed very unlikely to contain Black Guillemots. In 2021, a total of 718 Black Guillemots were counted around the coasts, with concentrations particularly high at The Maidens (60 individuals), Bangor (75 individuals), Lighthouse Island (60 individuals) and at Annalong Harbour (58 individuals). A volunteer-led productivity study found that their breeding success at Annalong was 0.5 chicks fledged per nest.

Volunteer-led monitoring of seabirds was severely impacted by COVID-19 restrictions in 2020, but surveys were able to be carried out by the National Trust and the Royal Society for the Protection of Birds. Tern colonies around Northern Ireland had a catastrophic year. Despite this, many seabirds, such as Guillemots, had a good breeding season. These surveys revealed that tern colonies around Northern Ireland had a catastrophic year, with Sandwich and Common Terns experiencing some of their lowest numbers since records began. However, despite declines in terns, many seabirds had a good breeding season. 2020 was a record year for Guillemots on Muck Island, with Ulster Wildlife recording 3,107 individuals present at the colony last summer, the highest number counted since the first record in 1987. Despite Black-legged Kittiwake populations experiencing a long-term decline in the UK as a whole, in Northern Ireland the decline is at a much slower rate, with some colonies actually showing an increase. In particular, Kittiwakes are going from strength to strength in south Co. Down, with volunteer-monitored colony there increasing in each year since 2015 (from 483 pairs to 717 pairs). Also in Co. Down, lucky volunteers were able to follow the breeding success of a colony of 22 pairs of Black Guillemots as they raised 11 young birds opposite their house during the lockdown. These good news stories for Northern Irish seabirds are only possible to report due to the dedicated efforts of our Seabird Network volunteers year after year. However, each year there are still sites that do not regularly receive any counts — can you help survey Northern Irish seabirds?

There were mixed fortunes for Northern Ireland’s seabirds in 2019, but monitoring that year also confirmed the importance of the country’s coastline for its 22 breeding seabird species. Key findings of the Northern Ireland Seabird Report 2019 include promising news about Kittiwake numbers. The Red-listed Kittiwake is in long-term decline in the UK as a whole, with numbers of breeding adults standing at less than half their 1960s total. However, this decrease is happening at a much slower rate in Notherern Ireland, and some colonies are actually showing a long-term increase. In 2019, Kittiwakes in Northern Ireland had a good year, with increases at all sites. The colonies The Gobbins and Muck Island fared particularly well, with numbers increasing by 68% and 65% respectively compared to 2018. Razorbills and Guillemots also did well in 2019, the former being recorded in its highest numbers since records began at Muck Island and the latter having its best year since 2016. It is not all good news, however. Fulmar numbers continue to decline, along with Black Guillemot, at Northern Ireland’s best known seabird haven, Rathlin Island. The annual recording of seabird numbers by volunteers is vital for capturing the long-term changes in Northern Ireland's breeding seabird population, and alerting policy makers to the need for conservation action.

Since 1986, seabird populations in the UK and Ireland have been monitored through the Seabird Monitoring Programme coordinated on behalf of partnership organisations by JNCC. Sample data on breeding abundance and breeding success of seabirds are collected from a large network of sites, both regionally and nationally, to enable species’ conservation status to be assessed. To examine trends at individual colonies, at country level and across the whole UK, it is essential that individual sites can be monitored consistently for many years. Data on breeding abundance – the number of breeding pairs or individuals – provide a medium to long term measure of how populations are faring. Data on breeding success/productivity – the number of chicks fledged per breeding pair – are regarded as short term or more immediate measure of population status. Studies at four key sites (Isle of May, Canna, Fair Isle and Skomer) provide information on adult survival, diet, phenology used to help to diagnose the changes in abundance. Additional information on survival rates at other sites is collected through the BTO’s Retrapping for Adult Survival (RAS) scheme (Horswill et al. 2016), although there are no current RAS sites in Northern Ireland. The SMP generates annual indices of abundance and breeding success from these data which are expressed as a percentage of the population recorded at sites in 1986 when standardised monitoring began (JNCC 2016). Where possible trends are given at the scale of the UK or country level, but where coverage is only possible at individual sites, the indices are shown at the site level. The SMP is a vital programme for monitoring seabird population trends between the full national censuses.