Acrocephalus palustris – Telor y Gwerni
One trapped in the Well Heligoland on 2nd June was the first for Skokholm and the first spring record for Pembrokeshire (RDB et al.). Along with differences in structure and plumage, the wing formula confirmed the identification; in the hand the second primary, which had a shorter notch than a Reed Warbler, was longer than the fourth primary and the end of the emargination of the third primary fell level with the tip of the eighth rather than the tenth.
The only other Pembrokeshire record was found on Skomer Island by Dave Boyle on the late date of 2nd November in 2009; singles on Skokholm between the 21st and 22nd September 1995 and on Skomer on 23rd September 1993 were both rejected by the Welsh Records Panel.
From the Skokholm Annual Report 2017