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Features Yellow-browed Warbler  |
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Mid-October is the prime time to be looking out for Yellow-browed Warbler, especially along the east and south coasts. Photo: Steve Young (www.birdsonfilm.com) Yellow-browed Warblers breed across Russia, extending east from the Urals as far as Kamchatka and south to Afghanistan, northern India and the Sea of Japan. In the northern Urals, their breeding range is just inside the boundary of the Western Palearctic, but every autumn they appear well inside the region in seemingly ever-increasing numbers. In autumn most of the breeding population probably migrates through north-eastern China, filtering down to the species’ winter quarters that extend from central Nepal south to the Malay Peninsula. The breeding zone is vacated in August and September and birds arrive in the winter range from mid-October, departing again in late March and early April. The middle fortnight of October is the peak time for Yellow-broweds’ arrival in Britain, but the first birds often turn up as early as mid-September and the last as late as November. Records in England are mostly along the east coast south to Norfolk and along the south coast from Kent to Scilly. A few birds are recorded inland or from western counties. The east is usally the first area to see the new arrivals, with southern and south-western counties getting their first Yellow-broweds a few days later.
In Scotland, the Northern Isles and east coast sites get most of the records, but the species also reaches the Western Isles in most years. In Wales, most records come from Bardsey Island, and the highest numbers usually coincide with major arrivals on the east coast. In Ireland, most Yellow-broweds are seen in the counties of Cork, Waterford and Wexford, with Cape Clear, Co Cork, recording the largest influxes, including at least 50 in 1985. In the 1970s the average number occurring annually was 76, but in the 1980s and 1990s it rose to 320. 1988 was a record year with 739 recorded, and in 2003 there were more than 500, but both totals were eclipsed in the autumn of 2005. October 2005 saw a huge arrival on the east coast, with record day counts at many sites: up to 24 at Spurn Point, 18 at Flamborough Head and 14 at Whitby, all in Yorkshire; 12 on Fair Isle, Shetland; 11 on Holy Island, Northumberland; 11 at Reculver, Kent; and 11 at St Abb’s Head, Borders. There were also 13 on Cape Clear and 10 at Mizen Head, Co Cork. In Scotland, at least 360 were reported, with more than 170 on Shetland and Fair Isle. That month’s total for the British Isles was at least 1,250, 75 of which reached Ireland. Wintering birds are becoming more common, perhaps due to the mild winters that Britain now experiences. In 2006-07 there were birds along the south coast from West Sussex to Cornwall – and some stayed well into April. So why do so many Yellow-browed Warblers reach Britain each autumn? Many theories have been proposed, including reverse migration, genetic mutation and natural dispersal. What is not in dispute is that the records of Yellow-browed (and related species such as Pallas’s Warbler) have increased more than could be due to the growth in the number of birders.
Yellow-browed Warblers have now been seen in most European countries, as well as in North Africa and the Middle East. In September 1987 one was even trapped in Senegal. The fact that regular records are now spread across Europe and into the Middle East suggests some kind of dispersal on a broad front. Perhaps we are witnessing a subtle shift in wintering range, with regular dispersal having become successful and led to overwintering and a subsequent return migration. Maybe the birds we are seeing have become genetically programmed to migrate this way, with Britain and Europe now on a new migration path and a new winter range slowly evolving. Whatever the reason, there is no doubt that this warbler, one of our smallest scarce visitors, is welcome whenever it appears. How to findThe best chances of finding long-distance wanderers from Siberia come when the prevailing autumn winds are from the east or north-east. Yellow-broweds are most likely to appear when high pressure over Scandinavia causes winds to blow across the North Sea to the east coast of Scotland and England. Coastal woodlands are the best place to check, especially if they include trees that attract insects, such as Sycamores. Yellowbrowed Warblers are very active birds, flicking though the branches and hovering to pick off a choice insect, and they are often found quite high in the canopy. Wait patiently and scan the trees for movement – sometimes they will join tit flocks and roam through the trees with them. Always listen carefully, as a Yellow-browed’s call-note is a loud and distinctive tsoeest, often providing the first clue to its presence. Where to watchThe sites listed below regularly record Yellow-browed Warblers and have been selected to offer a geographical spread. England
Scotland
Wales
Ireland
Related article: Yellow-browed and Pallas's Warblers and Firecrest
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Listen carefully for the Yellow-browed Warbler's distinctive call. Photo: Steve Young (
The number of Yellow-browed Warblers wintering
in Britain is increasing, possibly as a result of milder winters. Photo: Steve Young (No material may be copied or reproduced from this website without prior written permission - for more information on copyright and approval, email webmaster@birdwatch.co.uk. For full privacy and legal information, click here.
