Exciting Times

The period from mid-September to mid-October is one of the most exciting times of the year for anyone interested in bird migration. Summer visitors that have spent the breeding season here begin to head off in earnest, whilst their counterparts in mainland Europe often get blown or drifted across the North Sea and add to the migration spectacular.

During the right weather conditions, rare birds from both the extremes of west and east can also form part of these movements. So far this season has lived up to expectations and provided something for everyone.

Siskin by Edmund Fellowes

There have been record counts on the east coast of Siskins on the move. 2,129 were counted at Carnoustie, Angus, during the morning of 7 September. In Hampshire, 867 Grasshoppers Warblers have been trapped at one site and over forty thousand Swallows were counted over-flying Hengistbury Head, Dorset on 16 September.

Sabine's Gull by Joe Pender

The westerly gales have provided a seabird bonanza on the west coasts. 900 Sabine’s Gulls flew past Bridges of Ross, Clare on 17 September and birds also turned up on waterbodies in land-locked counties, with one Sabine’s Gull staying eleven days at Grafham Water in Cambridgeshire.

American waders are also widely distributed, with the largest arrival of Buff-breasted and Pectoral Sandpipers for many years. Seven species of North American landbirds have also been found in Britain and Ireland. Red-eyed vireo, Black-and-White-Warbler, Northern Waterthrush and Baltimore Oriole on the Isles of Scilly, and Buff-bellied Pipit, Swainson’s and Grey-cheeked Thrushes on the Northern Isles.

And it is far from over yet! This weekend saw a large movement of Black Terns through inland counties, involving several hundred birds. A single flock of 100 birds were seen at Standlake, Oxon. Meadow Pipits and alba wagtails (Pied and White), Swallows and House Martins were all counted in three figures at several sites along the east and south coasts and goose counts are beginning to increase.

Things should be a little quieter for visible migration watchers during thesettled weather over the next few days. Migrating birds fly over at a greater height, often not visible from the ground, during these conditions.

Autumn storms

The first autumn storms have hit and have had a big effect on migration already. During strong windy conditions, migration for smaller birds comes to a halt as they seek shelter and take the opportunity to rest and, if possible feed-up in preparation to continue their journeys.The day counts of visible migration at Spurn Point illustrate this perfectly. On Sunday 11 September, prior to the winds increasing, 2,280 Swallows were counted heading south over the Point; yesterday with gale-force south-westerly winds only 33 were seen.

Strong westerlies, particularly those associated with fast tracking storms that cross the Atlantic in a day or so often bring North American birds with them, and this weekend’s storm did just that; over thirty Buff-breasted Sandpipers arrived in the UK during the weekend. This high Arctic breeding wader leaves its breeding grounds in Alaska and western Canada during August and September, heading for the Paraguayan and Argentinian pampas. The eastern breeding birds complete this huge migration in one long flight over the sea from New England to Paraguay and Argentina, so are often prone to getting caught up in these fast tracking storms. The winds also brought the first American passerine to our shores, a Red-eyed Vireo, to the Isles of Scilly. This bird would have been making its way to northern South America or Cuba.

Red-eyed Vireo above by Joe Pender

In the UK early autumn storms also bring seabirds closer to land and provide the opportunity for observers to witness some impressive movements of these maritime birds. In the last three days, over ninety Sabine’s Gulls have been seen, from Cornwall to Dumfries and Galloway, and over thirty Grey Phalaropes have been seen from coastal headlands and a few inland reservoirs, including in the London area. Both of these are true oceanic birds.

Sabine’s Gull by Joe Pender

September and October are the most exciting months in a migration watchers calendar. Light winds at anytime during this period, particularly light southerly winds, can produce huge movements of pipits, finches and hirundines – Swallows, House Martins and Sand Martins - during September, and large movement of thrushes, buntings and larks in October. Strong westerlies can bring birds from North America, whilst strong easterlies can result in birds arriving from as far away as eastern Siberia.

So what can we expect over the coming weeks?

As the weather quietens down in the next few days and with winds from the south and east we can expect large movements of finches, pipits and hirundines, as they head off to Africa and we could see the arrival of few Red-backed Shrikes.

You can follow migration as it happens by checking out the BirdTrack maps and reports.