Provenance & quality
Data have been collected by Centre for Ecology & Hydrology (CEH) staff on the May National Nature Reserve, Scotland (56°11′N, 02°33′W) using standardised methods since 1987, and this work has continued to the present as part of the Isle of May Long-term Study (IMLOTS; https://www.ceh.ac.uk/our-science/projects/isle-may-long-term-study).
As part of this long-term study, data on seabird diving outside the breeding season was collected as part of a biologging project part-funded by the Royal Society for the Prevention of Cruelty to Animals. Data were collected using time-depth recorders during July – December 2008 for Atlantic puffins and razorbills and 2005 for common guillemots. The full methodology is available in the Supporting Information document attached to this record.