This dataset contains prey items of common guillemot Uria aalge and razorbill Alca torda observed during the 2018 breeding season at East Caithness Special Protection Area (SPA), Buchan Ness to Collieston Coast SPA and Isle of May National Nature Reserve, off the east coast of Scotland. Diet of these two species has been studied on the Isle of May since the 1980s (Harris & Wanless 1985, 1986; Wilson et al 2004; Daunt et al. 2008; Thaxter et al 2013). To our knowledge, only two previous studies of diet has been undertaken at Buchan Ness to Collieston Coast SPA (in 2006, 6km to the north of the site used in this study; Anderson et al. 2014; and in 2017, using a similar protocol as in 2018; Daunt et al. 2017), and one previous study of diet has been undertaken at East Caithness SPA (2017; Daunt et al. 2017). Full details about this dataset can be found at https://doi.org/10.5285/d7164910-17cb-44cd-bccd-6a9c31b6ed70

This dataset contains prey items of common guillemot (Uria aalge) and razorbill (Alca torda) observed during the 2019 breeding season at East Caithness Special Protection Area (SPA), Buchan Ness to Collieston Coast SPA and Isle of May National Nature Reserve, off the east coast of Scotland. The diet of these two species has been studied on the Isle of May since the 1980s. To our knowledge, the only previous studies of diet were undertaken at Buchan Ness to Collieston Coast SPA (in 2006, 6km to the north of the site used in this study; and in 2017 & 2018, using a similar protocol as in 2019), and previous studies of diet have been undertaken at East Caithness SPA (2017 & 2018). Full details about this dataset can be found at https://doi.org/10.5285/3d90a2b0-9a9e-4e39-8986-9082d1ec529e