Isle of May Puffin Population Drops 30% Due to Extreme Weather

A recent count of burrows on the island in the Firth of Forth found 36,500 occupied puffin burrows this year. This is a significant decrease from the 52,000 recorded in the 2024 survey and the 39,000 recorded in 2017. While the total number of burrows remained similar between 2024 and 2026, the occupancy rate was significantly lower this year.

Causes of Decline

NatureScot Isle of May Reserve Manager David Steel described the decline as disappointing and concerning, noting that numbers fell sharply in the 2000s, recovered during the 2010s, and have now dropped again. Steel attributed the decrease to poor winter survival, increasingly extreme weather, and ongoing pressures on food supplies.

Mark Newell, the UKCEH field manager on the Isle of May, stated that the population has likely suffered from a series of extreme climate events, including intense storms and marine heatwaves that affected survival in three of the last five winters. UKCEH research indicates that rising ocean temperatures can reduce the availability of sandeels, a primary food source for puffins, which impacts breeding success and survival rates.

Newell added that there is concern because climate scientists predict an increase in the severity and frequency of such extreme events in the future.

Monitoring and Methodology

The count was conducted over six days by field workers from NatureScot and UKCEH, who swept across the entire island to count holes in the ground and determine if they were excavated by rabbits or puffins. To determine the final number, a sample of plots was examined to establish occupancy, and a correction factor was applied to the island-wide count.

The UKCEH has monitored seabird colonies on the Isle of May for 50 years. Steel emphasized that the current trends highlight the necessity of continued conservation work and research at the reserve to help understand and respond to these challenges.