Calidris alba – PIBYDD Y TYWOD – Passage migrant and winter visitor.
The Sanderling has a circumpolar Arctic tundra breeding distribution, subsequently migrating to shorelines throughout the rest of the world, short of Antarctica. Those seen in North West Europe are from Greenland and Siberia.
The Sanderling was classified by early authorities as an autumn and occasional spring passage migrant to Pembrokeshire. Subsequent observations have confirmed the autumn passage but also shown that there has been an annual spring passage and a few winter occurrences. They have mostly occurred on sandy beaches and flats but have also been seen resting on rocky shores and by coastal pools like those on Skokholm , Skomer and Newgale Marsh and once running about on the dry runways of the disused Dale airfield. They have also been seen passing offshore from Strumble Head, the islands and The Smalls.
Autumn passage has been recorded from the 16th July to the end of November. The most favoured localities have been the Teifi Estuary (max. 15 on the 21st August 1987), Nevern Estuary (max. 18 on the 29th July 2005), Angle Bay (max. 25 on the 22nd September 2006) and Frainslake (max. 57 on the 21st July 1996). Transient birds have also been seen at popular bathing beaches, mostly involving one to four birds at a time but 12 were at Broad Haven (North) on the 2nd September 1985 and 50 there on the 30th July 1986.
Spring passage has been recorded from April to the end of June, most passing through during May, hence being a much quicker event than autumn passage and in terms of volume involving about half the number of birds.
The same localities were frequented in spring as in autumn, flock sizes being similar, the maximum recorded being 40 at Frainslake on the 18th May 1996.
Cumulative passage totals 1980 – 2006.
One to five birds at a time have been recorded during the winter period, December to March, initially in 1927 and 1929, then in 1961 and 1963, in 1983, 1985, 1987, 1991 and in every year from 1994 to 2006. Most records are for single dates but occasionally they have stayed for up to a month and in 1996 up to three were at Fishguard Harbour for six weeks and in 1997 up to three at the Gann for six weeks. Perhaps these were offshoots from the substantial winter population found at Cefn Sidan in neighbouring Carmarthenshire.
Graham Rees (County bird recorder 1981 to 2007)