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, 15 September 2017

More waders from the West

Several more North American waders were found this week, as the westerly airflow – very strong at times – continued to dominate. A Stilt Sandpiper appeared at Lodmoor RSPB, Dorset on 11 September, where it was quickly joined by a diminutive Least Sandpiper! The same or another Least Sandpiper was retrospectively identified on the Axe estuary, Devon on 7 September, after the astute observer recognised the Lodmoor bird and scrutinised his blurry photographs of a 'peep' that looked wrong for Little Stint but was too distant to identify in the field. The Spurn Migration Festival (aka Migfest) got in on the act too, with this blog's regular author, Paul Stancliffe, locating an incoming Long-billed Dowitcher...by its call!

Spurn's Long-billed Dowitcher shortly after it touched down, by Nick Moran

The American Redstart that was found on the remote island of Barra in the Outer Hebrides last week hung on, proving popular with Barra regulars and long-distance twitchers alike. It's the sixth living individual of that species to reach the UK but the first for 32 years (a long-dead one was found on a tanker in late December 1993, the ship having travelled from Texas to Shetland via Angola!).

The westerly storms also brought seabirds that are trying to make their way southwards through the North Atlantic close to – and even over – the mainland. West coast based observers enjoyed a glut of Leach’s Petrels and Sabine’s Gulls, whilst all four species of skua have been seen from both the west and east coasts. Great Skuas were very much in evidence on the east side of the UK on 14 September, with notable observations of 170 – including one flock of 110 – flying inland from Huttoft Bank, Lincolnshire and 62 that flew south over Foul Anchor, Cambridgeshire. These birds were presumably taking the known 'short cut' between the Wash and the Severn, though the large numbers involved were probably a result of the weather conditions.

Following the movements in the last few days, the BirdTrack reporting rate for Great Skua
must surely be set to rise towards its mid September historical peak

The storms also pushed a few Manx Shearwater far inland, with a bird taken into care in Ely, Cambridgeshire on 14 September and another found dead in Stowmarket, Suffolk.

Meadow Pipits have begun to move in earnest with over 11,000 individuals counted moving over Spurn, East Yorkshire during Migfest. These were joined by an impressive movement of Swallows and House Martins over the same weekend, when around 1,500 of each were counted. A few Swifts hang on, the BTO's own Nunnery Lakes reserve hosting one as late as 15 September.

Pink-footed Geese started arriving in the first week of September but numbers on the move increased in the last few days. The weather seemed to displace some of these, too, with a skein of 31 over northwest Worcestershire on 14 September being unusual so far south this early in the year.

Migrating Pink-footed Geese by Chris Mills

A mid September BTO Bird Migration Blog post couldn't end without mention of a popular – and increasingly numerous – migrant, Yellow-browed Warbler. Shetland received its first on 9 September, whilst mainland UK had to wait until 14 September, when birds were logged in Durham, East Yorkshire, Lancashire and Norfolk. Even the briefest 'window' in the weather will see more of these spritely Phylloscopus warblers arrive.

Nick Moran

Friday, 8 September 2017

Look to the west

Airflow from the west has dominated the last week and so it is perhaps not that surprising that Nearctic waders have been well represented. At least seven Baird's, five Semipalmated and five Buff-breasted Sandpipers were found, along with two Lesser Yellowlegs and two Hudsonian Whimbrels.

Buff-breasted Sandpiper by Ron Marshall

Yellow Wagtails are still on the move but have been increasingly joined by Grey and alba wagtails, the latter involving both White and Pied Wagtails. The last few days have also seen the first real movement of Meadow Pipits, with notable counts of 85 at Hengistbury, Dorset on 6 September and 250 moving over Portland, Dorset on the same day.

Meadow Pipit by Jill Pakenham/BTO

September is also the month to enjoy tern passage, and this week hasn't disappointed. Offshore movements of Common, Arctic, Sandwich and Black Terns being  reported fro several coastal watchpoints. When terns are on the move, skuas aren't far behind and a few Arctic and Great Skuas have followed the terns. As the month progresses, both tern and skua passage should build. Early September is also a good time to look for Long-tailed Skua at coastal watchpoints.

Reporting rate of Sandwich Tern on BirdTrack


Migrant passerines found in the last few days include Red-backed Shrike, Wryneck, Ortolan Bunting and Bluethroat arriving from continental Europe despite the westerly wind. Two other typical autumn migrants, Common Rosefinch and Barred Warbler should also start appearing at coastal headlands soon.

Barred Warbler by Moss Taylor/BTO

The weather forecast for the next four or five days suggest that westerly airflow will once again dominate, with several low-pressure systems set to cross the Atlantic. These will very likely bring more shorebirds, perhaps a few more Buff-breasted Sandpipers or American Golden Plovers to our shores in the days ahead. An American Redstart was found on Barra in western Scotland yesterday, the first record in Britain since 1985. Will more Nearctic warblers be found over the weekend?

This weekend sees the fifth Spurn Migration Festival – the BTO team are there all weekend. If you are planning on going to the festival, why not drop by and say hello to the team?

Paul Stancliffe and Stephen McAvoy

Friday, 1 September 2017

September is here and birds are on the move.

There are still one or two Swifts being seen over the BTO headquarters here in Norfolk but most have now gone, the last few will probably join them any day now. House Martins and Swallows are also on the move but with reports of nests containing young of both still coming in they will be around for a while yet.

One of the biggest movements seen this week has been Yellow Wagtail, around 1,000 were estimated to be on Portland, Dorset over the weekend, with around 200 still present on 29 August.

Yellow Wagtail by Jill Pakenham

A few Pied and Spotted Flycatchers and Redstarts and Wood Warblers have begun to turn up at coastal watchpoints, along with a few Tree Pipits. Willow Warblers have reached double figures at many too. A few Chiffchaffs have been mixed in with the Willow Warblers but it will be a couple of weeks before the numbers really start to build.

The first Fieldfare of the season was seen on Fair Isle on 29 August, giving a flavour of what is to come, and scarce migrants also began to feature, at least three Barred Warblers, 18 Wrynecks, two Greenish Warblers and a Woodchat Shrike and a few Red-backed Shrikes and Common Rosefinches.

Fieldfare by Edmund Fellowes

Scarce waders were also represented with around thirty Pectoral Sandpipers, four Buff-breasted Sandpipers and a scattering of Dotterel being seen during the week, but pride of place must go to the Pacific Golden Plover that was found on Papa Westray, Orkney on 26 August.

Ospreys have been reported from most counties and a few Honey Buzzards have been on the move too, so it is well worth keeping an eye on the sky during the next week.

Honey Buzzard by Graham Catley


The weather forecast for the early part on next week looks promising for the arrival of more Buff-breasted Sandpipers, with a low pressure system tracking across the Atlantic, we might also get something much rarer following on from the double-billing Yellow Warblers of last week. It’s about time we saw another Yellow-throated Vireo in the UK. During the early part of next week High-pressure over Scandinavia might just push a bit of east in the wind over the northern isles and could bring a few more Barred Warblers, Wrynecks and Red-backed Shrikes with it.

Friday, 19 May 2017

Hirundines in a hurry!

Ordinarily mid-May sees spring migration begin to slow but with northerly winds dominating the early part of the spring, several species seem to have been held-up, and the last few days have seen hirundines on the move, mostly House Martins but also smaller numbers of Swallows and Sand Martins too. Early indications from the BTO House Martin survey suggest that it is a slow start to their breeding season; perhaps there are still birds that haven’t arrived back yet.

There will still be plenty of birds on the move and, for some, now is the time to catch up with them. Arctic Terns will peak in the next week or so, mainly moving up the west coast but also through the Severn and Trent valleys, as some of them make their way into the North Sea. This is also a good time to look out for Long-tailed Skuas, with the very best site being Aird an Runair, the most westerly point of the island of Uist in the Western Isles.

Arctic Terns by Jamie MacArthur


Nightjars typically arrive back on their breeding territories around mid-May and migrants birds can be found almost anywhere, and if you stand any chance of seeing Golden Oriole in Britain, now is the time.

May is the month that Honey Buzzard arrive back and in the right weather conditions, move through the country. South-easterlies are what is needed, and if we do get winds from this direction in the next couple of weeks it could get exciting, with Red-spotted Bluethroats, Wrynecks, Red-backed Shrikes and Icterine Warblers turning up.

Red-spotted Bluethroat by Edmund Fellowes


The weather over the weekend is due to turn southerly for a short time with a hint of south-easterly early next week, whether or not this will be strong enough, or come from far enough east to turn up eastern bound migrants will have to be seen but it will be a change from the westerlies of the last week or so and a change in wind direction quite often turns birds up and allows others to move.

At this time of the year anything can turn up, as evidenced by the Great Reed Warbler that was found in a tiny reedbed on the BTO’s Nunnery Lakes reserve in Norfolk, the first for the site. It would be fantastic if it was followed up with a Crag Martin next week.

Great Reed Warbler by Mike Symes

Friday, 5 May 2017

Wind stuck in the north

With the wind stuck in the north migration has slowed a little but not come to a halt. Fortunately there has been varying degrees of east in the wind and this has resulted in what could be described as a Black Tern week, with birds being reported from many wetland and seawatching sites across the country.

Black Tern by Lawrence G Baxter
What is really obvious is the lack of Swifts. A small number have arrived but the usual mass arrival during the first few days of May hasn’t happened. The stiff northerlies are definitely blocking a mass arrival at the moment but as soon as conditions allow we should be in for an impressive movement of these amazing birds, this may well happen midweek when, if the forecasters are correct, we will experience a short period of light southerly winds.

This will also allow some of our later spring migrants to arrive too, and it is well worth looking out for Spotted Flycatchers. For those lucky enough to have easy access to the coast skuas, in particular Pomarine Skuas, will be on the move, along with more Black Terns, Little Gulls and Arctic Terns. South-easterlies are the ideal conditions for these and we might just be lucky midweek.

Pomarine Skua by Jo Pender
Now is the time to catch-up with a few waders as they make their way north, in particular Whimbrel, Dotterel and Wood Sandpiper.

Dotterel by Edmund Fellowes
We are just coming into the period when some of our scarcer migrants move and the right now is a great time to look out for Golden Orioles, Red-backed Shrikes and Wrynecks.

Friday, 28 April 2017

Migration about to spring into action - guest blog by Ben Porter

The nature of migration generally this spring has been one of sudden flurries followed by slow trickles. This week continued along much the same lines: a glorious weekend with a southerly airflow and wide isobars saw the floodgates open for northbound migrants to stream into the country. Coastal localities were inundated with Willow Warblers, Blackcaps and Wheatears, and species like Redstart, Sedge Warbler, Whitethroat, Ring Ouzel and Grasshopper Warbler took advantage of the passing weather front to move in from the continent. Then the traffic lights turned red: a complete flip in the airflow saw bitter northerly winds dominating for much of the week; temperatures plummeted into the single figures and flurries of snow and hail across the north of the UK further added to the week’s wintry feel.
Willow Warbler by Ben Porter

The calm conditions over the weekend made for some great arrivals here on Bardsey: bushes were brimming with Willow Warblers and Blackcaps; Grasshopper Warblers sent out reeling songs from the damper wetlands; Swallows and Sand Martins zipped northward overhead; and seemingly every grassy knoll and bank was topped with a Wheatear! Greenland-race Wheatears have been one of the dominating migrants on the island this week, their larger size and deeper orange belly contrasting with a flash of white as they alight with hard ‘chacking’ calls. An excellent arrival saw over 250 birds on the 20th, although the national reporting rate on Birdtrack still shows below-average occurrence. It looks like the pressure front next week is going to help these leucorhoa birds make their long-distance flights to the Arctic tundra via Iceland and Greenland.

Wheatears by Ben Porter
Wheatears by Ben Porter


Cuckoos and Turtle Doves have yet to make it over the Irish Sea to the island, although both species reached Scotland this week, with a Turtle Dove on the isle of Rhum and a Cuckoo in Lothian! Three of the BTO’s satellite-tagged Cuckoos are now north of the Pyrenees and should make the home stretch to join ‘Selborne’ with a brisk south-east tailwind in the next week. Keep up to date with their movements here

A smattering of colourful scarcities arrived in the UK this week, including Golden Oriole, multiple Hoopoes, at least three Bee-Eaters (one of which even paid London a visit!), White-spotted Bluethroats, Serin, Red-footed Falcons and the spring’s first Savi’s Warbler. We can expect to see plenty more of these overshooting continentals as we enter May, plus some non-passerine visitors such as Temminck’s Stints on inland reservoirs. Conversely, Waxwing numbers are likely to dwindle as birds continue to dissipate north-east – we still had around 600 birds in the country last week, although they were absent from Ireland, Wales and the South-west.

Whimbrels should arrive in earnest over the next ten days as we approach their peak spring reporting period. The numbers here on Bardsey Island are still below-average for the time of year. Contrast that to the national picture, and the reporting rate is slightly above the historical average, fast-approaching 7.5% of Birdtrack user’s lists. Keep an eye out for colour-ringed birds amongst migrating flocks: they are most likely to be from Iceland, but a few sites in the UK also carry out colour-ringing on these waders, including Bardsey Bird Observatory. Make sure you report colour-ring sightings and email the Iceland project (icelandwader@gmail.com) should you see any. It’s through anaylsis of ringing recoveries and recent satellite tracking that has revealed some impressive autumn movements of Icelandic Whimbrels from Iceland to North Africa. It’s also indicated that most birds on the east coast – both in spring and autumn – are likely to be Scandinavian.
Whimbrel ring recoveries from BTO. Whimbrel images by Ben Porter

Early May is one of the best times of year to catch up with trips of Dotterels as they touch down on hill tops and coastal spots en route to their breeding grounds. A scattering of birds have already been seen over the last week, including at favoured sites such as the Great Orme in North Wales. Lancashire’s Pendle Hill will no doubt host a few of these superb waders in the next few days.

So what of the week to come? A low-pressure system rolling in from the Atlantic over Saturday and Sunday will see the strong winds switching around to the south-east, which could provide the encouragement needed for migrants to move up through France and continue northwards in the UK. A widening of isobars and an area of high pressure over France and Iberia in the earlier part of the week should make for a good arrival of more warblers, chats and waders. Temperatures should climb a little higher too, which will hopefully encourage the invertebrate life to emerge and provide weary migrants with much-needed refueling!
Low pressure is due to arrive on Saturday - image from Met Office.


We’ve almost welcomed back the full complement of spring migrants as far as songbirds are concerned, although Spotted Flycatchers have yet to appear, and the peak arrivals of Wood Warblers, Pied Flycatchers, Yellow Wagtails, Garden Warblers and Lesser Whitethroats will probably occur over the next week or two given the promising outlook.
Spotted Flycatcher by Ben Porter
Spotted Flycatcher by Ben Porter

If you’re heading out over the weekend, listen out for the liquid gold song of the Nightingale – birds should be back on breeding territories very soon. The bright sunny weather forecast for early next week will be perfect for Common Swifts to scythe their way overhead in screaming flocks. If you haven’t already, why not consider fitting a Swift nestbox to your house? There is just enough time before they return! There are plenty of tips at www.swift-conservation.org

The reporting rate for Common Tern and Arctic Tern is on the increase, and the strong winds this weekend might make seawatching a productive option to spot flocks passing by. You might also be in with a chance of seeing Pomarine, Arctic and Great Skuas passing the coast. Rarities in the coming week could take the form of more overshooting continental migrants such as Black-Winged Stilts and Golden Orioles, although the south-easterly wind might favour perhaps a Collared Flycatcher, Citrine Wagtail or Red-throated Pipit even on the east coast.
Red-throated Pipit by Ben Porter
Red-throated Pipit by Ben Porter
This blog was kindly contributed by Ben Porter (@BardseyBen), www.benporterwildlife.co.uk.




Friday, 21 April 2017

Here come the Cuckoos!

The stop-start nature of this spring's migration has continued over the past week but breaks in the weather fronts allowed through a nice flurry of Ring Ouzels with over 60 records yesterday alone. Over the past week Ring Ouzels have been reported from the Isle of Wight to Edinburgh with 17 at Burnham Overy in Norfolk on the 20th April and 27 in the Cot Valley in Cornwall on the 18th April. Wheatears also arrived in good numbers and the graph below from BirdTrack shows that after a lag earlier on, the percentage of BirdTrack users seeing Wheatear has now caught up with the average for this time of year.

Graph showing percentage of BirdTrack complete lists featuring Wheatear
Graph showing percentage of BirdTrack complete lists featuring Wheatear

This is the best time of year to look out for Red-rumped Swallow and right on cue there have been half a dozen or so sightings over the past week. If you're visiting any coastal locations or freshwater marshes over the coming week look out for Swallows with very pale (sometimes reddish) rumps!


Red-rumped Swallow by Richard Crossley (The Crossley ID Guide Britain and Ireland) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

With high pressure dominating through well into next week we can expect a good arrival of migrants. We should see Pied Flycatcher, Whimbrel, Yellow Wagtail, Hobby and Arctic Tern all arriving in good numbers and more of our Turtle Doves returning too. We are receiving more reports now of House Martins returning to their nest sites, if you have any breeding near you then we need your help with our House Martin nest survey.

Three of our satellite-tagged Cuckoos are back in Europe now with one already back at his breeding grounds in the UK. Over the next two to three weeks we'll be heading rapidly towards the peak for Cuckoo records so if you want to hear a Cuckoo this year, this is the time to get out and listen. If you're very lucky you may even encounter an early Bee-eaterSquacco Heron or Purple Heron and it is worth looking out for rarer waders like Pectoral Sandpiper and Marsh Sandpiper stopping off on passage.

Cuckoo by Robin Lee
Cuckoo by Robin Lee

Over the course of the weekend, a cold weather front moving from north to south through Britain could produce a decent 'fall' of grounded migrants. Saturday morning looks like your best bet to head to a coastal watch point to witness this phenomenon for yourself, especially if there is a little rain early on . There is the potential for much colder weather early next week, with snow over much of Scotland and down to central England. How will our recently arrived migrants (and early breeders) cope with this cold snap?