Fig. 1

(a) Location of study site—Isle of May NNR, south-east Scotland, UK (56°11’N, 02°33’W) (b) Sub-colony sample sites for each species on the IOM. Sampling was spread across accessible sub-colony locations. Total sampling locations were as follows: puffins n = 2, shags n = 6, razorbills n = 9, guillemots n = 6, kittiwakes n = 8. Not all available species and colony sites could be sampled and broader species assemblages occur at all sites across the island.48,49.