Motacilla flava – SIGLEN FELEN – Passage migrant, has bred. Not recorded from December to February
The Yellow Wagtail has a breeding range spread throughout most of the temperate regions of Europe and Asia, extending into Alaska. The western European population winters in Africa. There are at least 15 subspecies, most of which are recognisable in the field. The subspecies which breeds in Britain is M. f. flavissima.
The following account refers to M.f. flavissima unless stated otherwise.
From the time of the first Pembrokeshire avifauna, written in 1894, to the present day, the Yellow Wagtail has principally been a passage migrant recorded in both spring and autumn. The exceptions were when a pair bred successfully at Lower Broadmoor, Talbenny, in 1997 and a pair behaved as if nesting in a potato field at Treginnis in 1983, which disappeared when the crop was harvested. In both cases the male was of the Blue – headed form M.f.flava.
The first record traced of Yellow Wagtails in Pembrokeshire which gave the number involved, the location and the date, was of five at Cilwendeg on the 24th August 1867 noted by Thomas Dix. It was 1930 before the next such record was forthcoming, followed by records in 1931, 1948 and 1949, in four years in the 1950’s, in eight years in the 1960’s, four years in the 1970’s and in every year from 1981 to 2008.
Yellow Wagtails have been recorded all around the coast, flying past or feeding on open ground, particularly pasture land with cattle. They have been seen on all of the offshore islands, even Grassholm, a large percentage of the county records being from Skokholm where there has been daily observation continuously since 1946. A few records were from the Teifi Marshes but very few from further inland, the only ones traced being five at Cilwendeg on the 24th August 1867, one at Crymych on the 7th June 1984, one Pen Gawse on the 6th May 1989, one Brynberian on the 2nd September 2001 and one Canaston Oaks on the 7th August 2008.
Yellow Wagtails have drastically declined in the UK since the 1980’s, by 70% between 1981 and 2006. This decline is reflected in the Pembrokeshire records as illustrated in the accompanying graph covering the years 1983 to 2007.
Pembrokeshire: trend in the number of birds per annum.
Spring passage has been recorded from the 3rd April to the 29th June, with early birds at Skokholm on the 17th March 1948 and on the 10th March 1956.
All dated records available 1867 – 2008, in six day periods.
The bulk of the passage has taken place between about mid April and the end of May involving small numbers as shown in the above graph, the maximum recorded in a day being ten.
Autumn passage has been recorded from the 1st July to the 30th October, with two November records.
There have been very few recorded in July and early August. Peak passage took place from mid August to September. The end of August has clearly been the time of maximum presence, when the largest concentrations of up to 50 birds were noted at Skokholm and Talbenny during the 1960’s. Betts (1992) notes “up to 150 in August 1952” at Skokholm but is not date specific, so these could not be fitted into the histogram. Passage has tailed off rapidly during October. There have been two November occurrences, on the 2nd at Mullock in 1981 and on the 18th at Skokholm in 1967.
Yellow Wagtail: pattern of occurrence
Graham Rees (County bird recorder 1981 to 2007)