On August and September 2012, the Sea Mammal Research Unit (SMRU) of the University of St Andrews carried out an aerial survey of moulting harbour seals (Phoca vitulina, also known as common seals) in the west, south-west, south and east of Ireland, between Galway Bay and Carlingford Lough. This was the completion of a survey of seals around the whole of Ireland that started in August 2011, when the coast from Lough Foyle to Galway Bay was surveyed (Duck & Morris, 2012). Although the primary aim of this survey was to count harbour seals hauled out ashore, grey seals (Halichoerus grypus) were also counted.

The 2011 and 2012 surveys were undertaken in order to update information from a previous nationwide aerial seal survey carried out in August 2003 (Cronin et al., 2004; Cronin et al., 2007). The surveys incorporated improved techniques which resulted in more accurate species identification and, consequently, more accurate final counts compared with the 2003 survey. This should be kept in mind when interpreting any differences in counts from the two surveys.