Breeding population size estimate for Ireland converted to specified units (pairs) based on detection estimates in Crowe et al. (2004) Bird Study 61: 82–90 and expert opinion.

In the absence of a report from the Czech Republic for this taxon, surrogate data were provided by ČSO / BirdLife indicating a breeding population of 2400–4800 pairs, with a decreasing trend (16–99%) during 2000–2012 and a decreasing trend (90–99%) during 1982–2012.

In the absence of a report from Greece for this taxon, surrogate data were provided by the Hellenic Ornithological Society (HOS), the BirdLife Partner in Greece, indicating a breeding population of 300000–630000 pairs, with a stable trend during 2007–2013 and an unknown trend during 1980–2012.