Numbers of puffins at one of the UK’s largest colonies have reduced by around 30% since 2024, a new survey has shown.
NatureScot and the UK Centre for Ecology & Hydrology (UKCEH) completed a count of burrows on the Isle of May National Nature Reserve in the Firth of Forth, a protected and internationally important habitat for seabirds.
Based on the count earlier this summer, scientists estimate there were 36,500 occupied puffin burrows, compared to 52,000 in the previous survey in 2024 and 39,000 in 2017. Puffin numbers on the island fell sharply in the 2000s and recovered in the 2010s but have now dropped again.
UKCEH has been monitoring seabird colonies on the Isle of May for 50 years, and our long-term research has shown that species have struggled with the impacts of climate change. Storms have killed large numbers of seabirds while rising ocean temperatures reduce the availability of food sources, particularly sandeels, which affects survival rates and ability to produce offspring.
Mark Newell, UKCEH’s field manager on the Isle of May, said “We believe that the puffin population has recently suffered from a series of extreme climate events, including marine heat waves and intense storms affecting survival in three of the last five winters.
“The concern for puffins and other seabirds is that climate scientists are predicting an increase in the frequency and severity of extreme events in future.”
Puffins can spend up to eight months of the year out at sea, only returning to land to breed in early spring. They generally mate for life, and pairs often return to the same nesting spot each year where the female lays a single egg.