Calidris alba – PIBYDD Y TYWOD – Passage migrant. Recorded in all months
Mathew (1894) and Lockley et al.(1949) agreed that the Sanderling was principally an autumn passage migrant but that a few were seen on spring passage. More recent observation has revealed that it is now annual in its occurrence, being seen on the outer coastline, the estuaries and the islands. Flocks of up to 24 occur between 12 March and 11 June and between 25 July and 16 November, with 50 at Broad Haven (north) beach on 30 July 1986. Fewer pass in spring than in autumn.
Despite the apparent suitability of our sandy beaches Sanderlings do not winter, but up to five short-staying birds have occasionally been seen from December to February, usually within the Cleddau Estuary, particularly at the Gann and Angle Bay.