BTO migration blog

Spring and autumn are exciting times for anyone who watches birds. Here on this blog we will make predictions about when to expect migrant arrivals and departures, so that you know when and where to see these well-travelled birds.

Friday, 30 August 2013

Migration steps up a gear

Autumn migration moved on with a bang during the Bank Holiday weekend. The conditions on Saturday into Sunday looked good for an arrival of birds from across the North Sea but nothing could have prepared us for the spectacle that unfolded.

Pied Flycatchers and Redstarts arrived in force at many east coast sites, as shown by the BirdTrack reporting rate graphs below. Whinchat migration also got underway, however, the majority of the birds seen at the weekend would be continental breeders on the move; ninety-two were counted on Saturday at Spurn Point, and over twenty Red-backed Shrikes were found.

But it was the scale of scarce and rare migrants that was most astounding. Over sixty Wrynecks were found during Saturday and Sunday, with twenty-seven being found at Spurn alone on Sunday. Over twenty Greenish and Icterine Warblers were found from Shetland to Dorset, along with as many as ten Booted Warblers.  Add to the mix, up to six Citrine Wagtails, two Short-toed Larks, a Bluethroat and a single Rose-coloured Starling and it was a very special weekend indeed.

Wryneck by Jill Pakenham

Waders were well represented too. Curlew Sandpipers flooded in. Over two-hundred were reported over the weekend, and as many as thirty Wood Sandpipers, and up to sixty Little Stints were found.

So, what can we expect this weekend? A westerly/north-westerly airflow will dominate, and with low pressure centred over Iceland any birds migrating south from there could well get pushed closer to our west coast. Waders such as Whimbrel, Black-tailed Godwit, Redshank and Golden Pover, should arrive. with the majority being juveniles. Amongst these look out for colour ringed Black-tailed Godwits, and if you do see any, report them to These waders could be found anywhere, so don’t despair if a visit to the west coast is not possible. A few Buff-breasted Sandpipers arrived in Britain and Ireland over the last couple of days and we could see a few more of these over the weekend, with maybe one or two more Wilson’s Phalaropes to add to the one currently in Northern Ireland.

Sabine's Gull by Joe Pender

Terns and skuas will also be on the move, now is a good time to look out for Long-tailed Skuas amongst the Arctics, see our latest Bird ID video for help with Skuas. Sabine’s Gull is also a strong possibility on the west coast this weekend.

Friday, 23 August 2013

Autumn migration

Whilst the weather still feels quite summery, for some of our birds the summer is well and truly over. Migration has begun in earnest and already flocks of terns, mainly Arctic, are being recorded moving down the west coast. This is a sure sign that skua passage is about to start too, and the next couple of weeks should see this take place.

Waders have been on the move for over a month but with juveniles now joining the adult birds, this is probably the best time of the year to get out and enjoy these global wanderers. Gravel pits and the muddy fringes of inland lakes can just as easily turn up passage waders as coastal sites, so don't be disheartened if you live a long way from the sea. Green Sandpipers are currently well represented but during the next week or so, these will be joined by more Wood and Curlew Sandpipers. Little Stints are also beginning to turn up and if we get a bit of east in the wind, Temminck's Stints could also feature.

Whimbrels have started to leave their northerly breeding grounds and flocks have been seen migrating far out to see, passing a survey vessel 100 miles southwest of the Irish coast. For more birding news from the survey vessel read the Pelagic Birder blog here.   

Above: Whimbrels by Andy Williams 

Passerines are popping up at coastal watchpoints with Redstart, Spotted and Pied Flycatchers all being found. Swifts are pouring out of the country and House Martins and Swallows are also beginning to move is smaller numbers.

The warm southerly airflow that we are in at the moment has resulted in a couple of Woodchat Shrikes, a Short-toed Lark and a Black Stork already, but we could see more arriving from the continent over the next couple of days. Wryneck and Hoopoe might well be on the cards, and perhaps an autumn Bee-eater or Alpine Swift too.

Saturday and Sunday are forecast to have an easterly element in the wind and this could bring a few birds from the east. Greenish Warbler and Rose-coloured Starling are favourites, and Aquatic Warbler might be expected too. Aquatic Warbler is now much rarer than it used to be as a passage bird in the UK but it is still worth looking out for in mid to late August when easterly winds occur.

Monday, 5 August 2013

There and back again

Two months have snuck by since our last update. It's been anything but quiet for migrant birds during that period though. June will be remembered by some as the Month of the Rare Swift, with long-distance (and very lost) travellers in the form of a Pacific Swift and a Needle-tailed Swift reaching our shores. Rare seabirds soon got in on the action when an exquisite Bridled Tern appeared on the Farne Islands in early July, quickly followed by an even more astounding sight: an Ascension Frigatebird found resting on a harbour wall on Islay on 5 July!

Lots has been happening amongst our more familiar species too. All our satellite-tagged Cuckoos have departed, with several already south of the Sahara! Some juvenile Cuckoos will still be in the country but the vast majority of these are also expected to leave in the next couple of weeks. (Common) Swift numbers are starting to drop off too, though as of last week they were still being recorded on about 30% of BirdTrack complete lists.

Arctic-breeding waders, restricted as they are to a short breeding season, are already heading south again. Wood Sandpiper, Little Stint and Spotted Redshank are amongst the many wader species that can be encountered at this time of year, and certainly spice up late summer birding trips.

Spotted Redshank by Chris Mills
Some Spotted Redshank retain their breeding finery into early August.
Chris Mills

In some years, July sees an influx of Common Crossbill, presumably involving a high proportion of Scandinavian-bred birds. This July certainly lived up to its (cross)billing, as the BirdTrack reporting rate below shows. Furthermore, it wasn't just the more familiar Common Crossbill that arrived but also unusually large numbers of their much rarer cousin, Two-barred Crossbill. This species breeds in Scandinavia and eastwards, lending weight to the suggestion of a Scandinavian origin to these influxes. The geographic spread of the Two-barred Crossbill arrival was noteworthy: whilst influxes are often confined to or at least concentrated on the Shetland and Orkney islands, this year's arrival featured multiple records down the English east coast, from Spurn to East Anglia. 4 birds even had the good grace to spend a few days less than 15 minutes' drive from the Nunnery, providing a nice lunchtime distraction for many BTO staff members!

BirdTrack reporting rate: Common Crossbill
The Common Crossbill influx as reflected in the BirdTrack reporting rate.

A round-up of migration activity in early August wouldn't be complete without a mention of the seabirds passing through British and Irish waters at this time of year. Whilst southern Ireland has had the lions share of goodies (including up to 3 individual Fea's Petrel in one day, plus an even rarer Bulwer's Petrel), counts of several thousand Manx Shearwater have already been recorded from southwest Cornwall on several dates. Whilst this species breeds on offshore islands in Britain and Ireland, some of the other species already logged by seawatchers in the southwest have come from much further afield. At the end of July I was lucky enough to see a scarce Great Shearwater whilst on a 'pelagic' (a boat trip in search of pelagic seabirds). This species breeds no nearer than the island of Tristan da Cunha in the South Atlantic, one of only a very few species to migrate north to winter in the North Atlantic.

Great Shearwater by Martin Elliott, Mermaid II pelagic
'My' Great Shearwater, a few miles south of Land's End.
Martin Elliott