Fair Isle mini-blog: The long road north

Several BTO staff are spending a few days on Fair Isle, hoping that the weather sends some interesting migrants their way.

Most of our first day was spent in the car, leaving Norfolk and 4.15am and arriving on Shetland at 3.00pm. That doesn't mean we didn't see any birds though. Soon after first light it became apparent that there was a major migration event unravelling. Flocks of Redwings were a constant feature from South Yorkshire to the Scottish border, along with smaller numbers of Fieldfares.

Once on Shetland we went in search of a Buff-bellied Pipit, a stray from North America. This was partly successful, in as much as a third of the party saw the bird (John Marchant and Paul Stancliffe).


The field that the bird was in, eventually, was also a magnet  for migrants. 12 Swallows hawked over it, four Bramblings fed with the local Twite, a Whinchat sat on the fencewire, 25 Redwings joined the 10 or so migrant Blackbirds, and 2 Goldcrests fed in the adjacent ditch, sharing it with 3 Jack Snipe. And then it got dark

Tomorrow we leave for Fair Isle, weather willing. There is a strong southerly wind at the moment and it is around 9 degrees.

Paul Stancliffe

Here come the nomads

Over the last few days we have seen an arrival of Short-eared Owls at many East Coast sites, suggesting these are birds arriving from elsewhere in Europe. We receive a substantial influx of Short-eared Owls most autumns, with numbers increasing from August through to November. Information gleaned from ringed individuals suggests that many of these birds will be from Finland, Norway, Sweden and the Low Countries. Interestingly, the BTO ringing database also holds records of one from Iceland and one to the Faeroes, highlighting the wider origins of some birds.

Wintering Short-eared Owl, by Amy Lewis

Short-eared Owls have a reputation for being wanderers, avian nomads that seek out the opportunities offered by prey populations whose numbers can change dramatically from one year to the next. This nomadic behaviour is not restricted to the autumn and winter but can also be seen in breeding birds. The numbers breeding on favoured moorland sites across northern Britain may vary considerably between years as the birds respond to the availability of small mammal prey, particularly Field (or Short-tailed) Voles.

Birds that breed on our moorland will move to lower ground come autumn, favouring downland, rough grazing land and coastal marshes, where they may mix with individuals that have arrived from further afield. Some of our breeding Short-eared Owls will themselves make a sea-crossing, choosing to winter in France and Spain, again highlighting the fluid nature of this wandering owl.

East meets west

Most of the focus during the early part of the week was in the west, with Leach’s Petrels being the stars of the show, good numbers of which moved down the west coast in stormy conditions. Now that the wind in the North Sea has dropped the migratory focus has switched the east.  

Goldfinches have dominated, with some impressive day counts at migration watchpoints. At this stage of the autumn it is the finch movement that will be most obvious, and this has been very much the case over the last couple of days. Linnets, Redpolls, Siskins, Crossbills, Bramblings and a small number of Hawfinches have all been in evidence, particularly on the east coast. Some of these finches will move into gardens in search of food as the wetter conditions cause the pine and alder cones to close, making the seeds difficult to access, others will continue on their journey south and could also provide a visible migration spectacular on the south coast.

Linnet by Jill Pakenham

Flocks of Redwings and smaller numbers of Fieldfare have also begun arriving with these birds moving inland very quickly in search of food, so garden birdwatchers will also be able to see this migration in action. Goldcrests have also been a feature of the last day or so.

With the wind forecast to turn south and south-easterly for the weekend, we can expect a migration spectacle. The winter thrushes should arrive in large numbers and most of us should catch-up with our first birds of the autumn. The finches will be on the move and more Goldcrests, along with a few Woodcock should feature.

Woodcock by Herbert and Howells

The east coast will be the place to be, particularly on Saturday, and the vanguard of this movement has already begun. Double figures of Short-eared Owl have arrived on the Norfolk/Suffolk coast today, and flocks of Crossbills have been moving overhead.

Light rain on Sunday could result in the first falls of the autumn, with the east coast again being the place to be, but with thrushes on the move and finches turning up in gardens there is the promise of something for all in what could be the biggest movement of birds of the autumn so far.

Migrants not fooled by the heat

The unseasonably hot weather coupled with southerly winds has made for interesting times. The last few days have felt more like August than September/October, at least here in East Anglia, and it is easy to think that migrant birds feel the same. Visible migration has been quiet, with the large movements of Swallows and pipits of the previous week largely absent. However, this doesn't mean that the birds have been lulled into a false sense of security and have stopped moving; far from it. Where migrants have been visible there have still been relatively good numbers of both of these, along with finches, but for those of us birding under clear blue skies these are almost impossible to see as they will be migrating at a greater height than they would under less opportune conditions.

Redwing by Jill Pakenham

So, what has been happening? Swallow numbers have been much reduced, which is to be expected at this time in the season, the majority having already departed the country. However, as the Swallow numbers fall the House Martin numbers are growing as these wonderful birds now begin to get a move on. There have been good numbers of wagtails on the move, predominantly Pied, or to be correct, ‘alba’ wagtails; Pied and White Wagtails are very difficult to separate with fly-over views, and the first real autumn movement of Skylarks has also begun.

The Northern Isles received their first fall of winter thrushes, hard to imagine when the temperature in the south is 29°C; over a thousand Redwings arrived on Fair Isle on Saturday alone. Goose numbers continue to build, with some flocks of Pink-footed Geese in the low hundreds recorded over the weekend. Ducks have also started to arrive with some impressive movements of Wigeon, also over the weekend.

Glossy Ibis by Edward Charles Photography

As was to be expected with the warm southerly airflow, birds from that direction arrived, and the first of the now annual flocks of Glossy Ibis turned up; seven were found together on the Isle of White, with three settling nearby on Stanpit Marsh, Dorset, and a flock of eleven were seen at Courtmacsherry, Cork.

Just when it seemed that things were quietening down from the west, the Sandhill Crane from North America, possibly a left-over from Hurricane Katia, decided to leave its temporary home in Aberdeenshire and become the first ever of its species to be seen in England. Previously there have been two records in Shetland and one in Ireland, the latter in 1805. This sudden appearance south of the border, and not too far from the BTO headquarters, prompted a good number of BTO staff to abandon their Sunday lunchtime activities in favour of a mega-twitch.

Sandhill Crane by Andy Mason

With the end of the heat-wave and the return to strong westerly gales forecast to hit the north of the country on Saturday, there could be another arrival of birds from North America with the Northern Isles being the place to be.

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.

Seabird Bonanza

The westerly gales that have been battering the coasts from the Cornwall to the Outer Hebrides have resulted in some spectacular seabird counts, in particular the rarer shearwaters. During the last week, over 7,000 Sooty Shearwaters, 2,500 Great Shearwaters and 600 Balearic Shearwaters, the latter globally listed as critically endangered, were counted off south-west Cornwall, south Devon and south-west Ireland. Among these were also numerous Grey Phalaropes, Leach’s Petrels and Sabine’s Gulls. Large numbers of Gannets and, as predicted in last week’s blog Manx Shearwaters were also seen in good numbers. Some newly fledged young of the latter struggled with the stormy conditions and 491 found themselves ‘wrecked’ on Newgale beach in Pembrokeshire. The BirdTrack reporting rate shows nicely the increase of observations of this species.

Manx Shearwater by Joe Pender

All four species of Skua were also involved in this movement, with Arctic being the most numerous, again the BirdTrack reporting rate shows this increase.

As was to be expected, the fast tracking Atlantic gales brought North American Waders with them and over a dozen Buff-Breasted Sandpipers arrived on our shores, with the Isles of Scilly hosting five of them, again the west received the lion’s share but birds have been found at Rye Harbour in East Sussex and Titchwell in Norfolk.


Buff-breasted Sandpiper by Joe Pender

Despite the windy conditions Swallows and Meadow Pipits have been a feature of visible migration watches. Over 12,500 Swallows were counted heading south at Spurn Point last Saturday, with almost 8,000 Meadow Pipits heading in the same direction on Thursday.

Swallows gathering by Paul Stancliffe/BTO

The first large finch movement was also observed here on Thursday with over 600 Siskins also heading south.

With the wind set to increase again from the west yesterday, observers on the west coast should have been in for another weekend seabird fest, whilst in the east, finches and pipits should make the most of any lull in the windy conditions.

Question of the week - How do birds cope with the risks of migration?

The very act of long-distance migration has to be one of the most arduous and dangerous activities that a bird undertakes, so what can they, and indeed do they do to minimise the risks associated with long-distance migration?

For those migrants that undertake long sea or desert crossings, it is essential to store enough fat deposits to fuel these flights and many of our smaller birds spend up to three weeks feeding up and accumulating fat reserves before their departure, some will have more than doubled their normal weight.

Setting off in optimum conditions also helps to minimise the risk of being downed or blown off-course and also maximises the stored fat reserves. If birds encounter worsening conditions, many will make landfall and rest-up and feed-up until conditions improve.

Some birds migrate primarily at night, reducing the risk of predation by diurnal raptors. Flying in the cooler night air also reduces drag and minimises the use of the stored fat reserves.