The latest Scottish Biodiversity Indicator for Seabirds assessed 19 of the 24 seabird species that breed around our coasts between 1986 and 2024. On average, seabird numbers are now around half of what they were in the 1980s.
Using data from the UK Seabird Monitoring Program, the study found that almost all seabird species studied have declined over the long term, with eight species significantly affected. Worst hit, Arctic skua has seen a 93 percent decrease in numbers since 1986, followed by little tern (75 percent) and common tern (73 percent).
Meanwhile, overall seabird breeding success (the number of chicks produced) is also decreasing over the long term, with eight of the 16 species surveyed showing lower productivity than the three-year average (average being around 75 percent of the 1986 level).
More positively, the breeding success of black-headed gull, guillemot, and puffin has stabilized over the last three study years (2022–2024). Over this short-term period, great black-backed gull and gannet had higher than average success in 2024; this contrasts with the long-term trend for gannet due to the effects of avian flu. Breeding success fluctuates from one year to the next, reflecting the immediate impact of food availability, weather events, and predation.
NatureScot Marine Ornithologist Bex Outram said: “Scotland is home to more than 60 percent of the UK’s seabird population. Our seabird colonies are world-renowned, contributing significantly to wildlife tourism, worth an estimated £127 million to Scotland’s economy each year.
“But many of our seabirds are under threat. Climate change, food shortages, invasive species, and other human pressures are contributing to their decline. Disease outbreaks like avian flu and extreme weather events have also had devastating impacts.
“As part of the Scottish Seabird Conservation Action Plan, work is underway to help secure the future for Scotland’s seabirds. Efforts are focused on three key areas: safeguarding food supplies, restoring habitats, and maximizing seabird survival. These efforts will take time to have an impact, which is why long-term monitoring coupled with advances in technology to improve our understanding of seabirds is vital.”
For example, Scottish Marine Environmental Enhancement Fund (SMEEF) has supported costs towards the purchase of 40 bespoke GPS tags, eight mobile base stations, and two fixed base stations for the tracking of northern fulmar on St Kilda and the Fair Isle. Using the technology of these tags will enable the tracking of the birds’ foraging behavior and will support the National Trust for Scotland (NTS) to understand far more about the challenges that are driving their decline.
