Abstract

Three severe gales in northern Britain between 26th November and 31st December 2021 resulted in a wreck of Puffins Fratercula arctica along the coasts of northeast Scotland, Orkney and Shetland. Of 532 corpses counted, 367 (69%) were adults. Data from the deployments of geolocators at colonies throughout the Northeast Atlantic predicted that there would have been c.81,000 adult Puffins in the area where storm conditions were most severe, of which c. 22,000 would have been from the colony on the Isle of May, c.42,000 from other North Sea colonies and c. 17,000 from elsewhere. Mortality of Isle of May adults over winter 2021/22 was estimated at 19%, compared to the normal 7%, suggesting c. 9,000 excess deaths in the population. If, as seems likely, the extra mortality was due to the storms, then 41% of the Isle of May adults present in the storm area would have died. Furthermore, if adults from other colonies experienced similar losses, an estimated 33,000 adult Puffins would have died due to the storms, which equates to 90 times more than the number of dead birds recorded washed up on beaches during the wreck.