The most remarkable week ever in Welsh birding

Fast-moving Atlantic low-pressure systems in the autumn trigger expectation among west-coast birders hoping to find a North American songbird. Most storms occur in October, when the majority of southbound migrants are already well out of the way, but ex-hurricane Lee last week deposited an unprecedented number of vagrants into Britain & Ireland. Hundreds of birds probably made landfall, most never to be found in remote coastal areas, but of those that were, Wales was the focus for some of the rarest.

Pembrokeshire kicked off last Wednesday with Wales’ first Alder Flycatcher on Skokholm and first Magnolia Warbler on St Govan’s Head. On Thursday, Wales’ fourth Bobolink was found on Skokholm, first Bay-breasted Warbler on Ramsey and a Red-eyed Vireo near Porthcawl. North Wales joined the party with Wales’ second Black-and-white Warbler found by ringers on Bardsey. Friday brought Wales’ first Cliff Swallow to Sker Point and another Bobolink was reported in the Vale of Glamorgan. Remarkably, young Chester-based birder, Toby Phelps, who found the Magnolia Warbler, only the third ever in Britain, surpassed that on Saturday morning with Britain’s first Canada Warbler at nearby Flimston. Saturday brought a second Black-and-white Warbler to Bardsey, now the only two ever to be ringed in Europe and another Cliff Swallow found by birders visiting Ramsey. Sunday saw, incredibly, a second Magnolia Warbler, this time at Briton Ferry near Port Talbot, but bad weather frustrated clinching the identification of an American flycatcher at Pen Cilan, near Porth Neigwl. 1 in 6 of the North American songbirds ever recorded in Wales arrived last week, and there may be more to find, with more storms forecast from Wednesday.

In four days, five species never previously recorded in Wales have been seen. For context, the average number of new species added to the Welsh List each decade since 1900 is 14, so last week was genuinely unprecedented.
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Lost migrants, by their nature, fail to add their genes to native populations but Dr Alexander Lees, Reader at Manchester Metropolitan University and co-author of Vagrancy in Birds, warns that climate change could magnify the impact of such events: “tens, maybe hundreds of thousands of migrant birds, will have drowned in the Atlantic before a few make European landfall. Increasing storm severity will lead to a temporary increase in vagrants, but in the longer-term population size could be affected”.