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 October 2015

Migration slowing down

Short-eared Owl by Amy Lewis

Migration is slowly winding down, but there are still a few birds on the move. There were a few reports of House Martin, Swallow and Wheatear and a few of all three species may well linger into November or even later given adequate food supplies and favourable weather. Finches will still be on the move, especially during quieter spells in the weather - Linnets, Redpolls, Chaffinches and Bramblings are the ones to look out for in particular. Reports of Yellow-browed and Pallas's Warblers are starting to tail off after a great autumn for both species, reaching 4% and 2% of all submitted lists into BirdTrack this month. There were also good numbers of Short-eared Owl reported around Britain.

Short-eared Owl BirdTrack reporting rate

Yellow-browed Warbler BirdTrack reporting rate

The mystery bunting on Orkney was relocated earlier this week and the identification confirmed as Chestnut Bunting. Showing incredibly well at times, this could well be accepted as the first (wild) record for Britain after a series of records currently listed in Category E. One of the species predicted last week did turn up, with a Chimney Swift seen briefly in Cork on Monday.

Grey-cheeked Thrush by Bryan Thomas

The weather looks distinctly mixed for the week ahead, with south to south-easterly winds for southern Britain and continued south-westerlies for Ireland and Scotland. During spells of light winds and clear conditions we might see Woodpigeons move, possibly in large numbers. A series of fast moving low-pressure systems look set to cross the Atlantic later in the first week of November, which may well bring some Nearctic vagrants (Grey-cheeked Thrush, Blackpoll Warbler and Cedar Waxwing). From the east, Asian Desert Warbler or Desert Wheatear are typical late October - early November rarities.

Stephen McAvoy and Paul Stancliffe

Friday 23 October 2015

Migration continuing apace

Starlings by Jill Pakenham

As is to be expected at this time of the year, it has been a busy time on the migration front.
Redwings have continued to arrive and have been seen across most of the country, the BirdTrack reporting rate shows this strong arrival well. Compare this to the reporting rate for Fieldfare which historically has a later peak time of arrival – there is still plenty of time to them to flood in too.
Song Thrushes and Blackbirds have been more obvious in the last week, along with Starling but all three of these should peak in the next week or so and we could see big arrivals of all three during breaks in the weather, particularly during periods of lighter winds.

Fieldfare BirdTrack reporting rate

Redwing BirdTrack reporting rate

Goldcrests continue to arrive in incredible numbers and at times the Norfolk coast, at least, seemed to be inundated with these incredible little migrants. Robin numbers also continued to impress at some east coast sites. On the finch side, Redpolls began to appear at migration watchpoints and following on from the incredible Yellow-browed Warbler autumn that we have experienced so far, Pallas’s Warblers have shown a slight return to form, having been quite scarce for a few years.

Great Grey Shrike by Trevor Codlin

As mentioned in our previous blog post (, Great Grey Shrike was one of the species to look out for this month and they certainly turned up. The reporting rate for this week was well over 2% of all BirdTrack lists, which dwarfs the historical average of around 0.5%. Most records so far have been from the east and south-east, with a few reports from Wales as well.

Great Grey Shrike BirdTrack reporting rate

Generally, wildfowl numbers are still on the low side, with the exception of Teal, but with low temperatures in Eastern Europe and western Russia this could change as and when waterbodies start to freeze.

The rare migrant highlight of the week is the Chestnut Bunting on Papa Westray, Orkney which was seen very briefly on Monday and Tuesday. There have been several previous records of this species, but so far all have been placed in Category E as escapes/releases from captivity could not be ruled out. Given the prevailing weather conditions in recent weeks and associated movements of birds with similar breeding ranges, it is possible this individual may be accepted as a first for Britain if the identification is confirmed.

Ovenbird by Bryan Thomas

 Looking ahead to next week, the weather at the moment looks set to be dominated by several low-pressure systems sweeping across the Atlantic. Grey-cheeked Thrush and Blackpoll Warbler are very typical late October vagrants from North America and SW Ireland and the Isles of Scilly look like the best places to find them. Outside bets include Chimney Swift, Yellow-billed Cuckoo and Ovenbird, all of which have multiple records in late October.

Paul Stancliffe and Stephen McAvoy

Friday 16 October 2015

Look to the east

Everything was in place this week for there to be a large arrival of winter visitors to the UK. With high-pressure and settled weather over Scandinavia, and high-pressure extending from the North Sea to central Russia, the resulting east-north easterly airflow, accompanied by showers on the east coast of Britain, ensured that we would not be disappointed.

Goldcrest by Jill Pakenham

Redwings poured into the country and smaller numbers of Fieldfare arrived too, moving rapidly south; the Isles of Scilly saw its first small flocks. Finches continued to move and the Goldfinches, Linnets and Chaffinches included a few more Bramblings. However, the week was dominated by the arrival of Goldcrests on the east coast. The BirdTrack reporting rate shows this arrival well. Equally impressive was the number of Great Grey Shrikes that arrived with them, no doubt taking advantage of the abundant supply of crests. As expected with the arrival of the Goldcrests a few Woodcock were also seen. Robins crossed the North Sea in force, along with the first noticeable arrival of Blackbirds.

Goldcrest BirdTrack reporting rate

A number of Pink-footed Geese made it to their wintering locations in north Norfolk, and wildfowl were on the move too. Several hundred Shoveler were observed arriving in off the sea at Burnham Overy, Norfolk on 15 October and a Bewick’s Swan that arrived at Slimbridge, Gloucestershire on 11 October was the earliest - by twenty-five days - to have ever arrived at the site since a study on this species began in 1963.

Shoveler by John Harding

With easterly airflow dominant throughout the week it was no surprise that many of the scarce and rare birds came from this direction, and around fifty Richards Pipits were found from Shetland to the Isles of Scilly. There was also a multiple arrival of Red-flanked Bluetails, with at least seven being seen. However, the biggest surprise, given the direction the winds were coming from, came from North America in the shape of Britain’s second ever Wilson’s Warbler that was found on Lewis, Outer Hebrides.

So, what to look out for during the next week?

Woodlark by Derek Belsey

Mid October is the peak time for two migrating passerines: Woodlark and Brambling. The former breeds in southern Britain and East Anglia, as well as more locally in the Midlands and East Yorkshire. At least part of the population moves away from breeding sites, some even to continental Europe and now is a good time to listen out for their distinctive flight calls (

Woodlark BirdTrack reporting rate

The first Brambling are beginning to arrive in Britain including one or two at our Nunnery Lakes reserve. The numbers of Brambling wintering in Britain fluctuate every year, most likely in response to the availability of beechmast in southern Scandinavia and eastern Europe. Several million birds can gather in areas with a high beechmast productivity and spectacular numbers can reach Britain and Ireland if it is a poor year for beech - for example an estimated 150,000 were noted near Liverpool in 1981. Could this be one of those years?

Arctic Tern by Andy Mason

With the wind likely to stay east to north east over the weekend, this may be a good opportunity for a late seawatch on the east coast of Britain. Scarcer migrants likely to be seen include Sooty Shearwater, a late Arctic Tern and Pomarine Skua. Reporting rates for the latter to BirdTrack peak in September, but October still sees a good number of records. There were also several of inland Gannets from Cambridgeshire, Derbyshire and Lough Neagh in Northern Ireland so even if you are not on the coast it is well worth checking local lakes and reservoirs for displaced seabirds.

The hands-down rarity of the week is the stunning Wilson's Warbler found on the Western Isles during the week. With the winds staying easterly for now, we are sticking with our guns in predicting a Siberian mega for the days ahead: another Chestnut-eared Bunting on Shetland perhaps? Or Britain's first Grey-necked Bunting on the Norfolk coast?

Paul Stancliffe and Stephen McAvoy

Friday 9 October 2015

Lesser Redpoll by Trevor Codlin

When buntings and finches are on the move you know that autumn migration is well underway. Flocks of the former, including good numbers of Goldfinch, Redpolls, Siskin and Linnet have been reported flying over several migration watchpoints from across Britain during the week, with a few Bramblings joining them. Reed Buntings and Yellowhammer have also been on the move. Peak migration for most of our finches and buntings is around mid-October so we can expect a lot more to come, and with high-pressure over Scandinavia and relatively light easterly winds, at least for the southern half of Britain, forecast for this weekend, we could see more finches, buntings and, on the move and some spectacular visible migration over the next few days. Swallows and House Martins will still be on the move along with Chiffchaffs and to a lesser extent, Willow Warblers.

Wildfowl will also continue to move and we could see Pink-footed, Barnacle and Brent Geese on the move in good numbers, along with some Whooper Swans and possibly Bewick’s Swans. Good numbers of the latter were recorded flying over Falsterbo, Sweden during the middle of the week.

Richard's Pipit BirdTrack reporting rate

With 12 reports throughout Britain and Ireland on Thursday and several more today (including on at least two ships), one of the top species to keep an eye out for this weekend is Richard's Pipit. Most records are of fly-overs, so it is a good idea to listen to the distinctive call ( before heading out. Coastal records predominate in BirdTrack, but there is also good scattering of reports from inland sites.

Lapland Bunting by Dawn Balmer

Lapland Bunting BirdTrack reporting rate

Another species regularly recorded as fly-overs only is Lapland Bunting ( Mid-October is the peak reporting time in BirdTrack, just about reaching 1% of all lists. A bit more exciting to look at than fly-over pipits and buntings, mid-October is also good to look for migrant Great Grey Shrikes. With a bit of luck, you could even see one trying to catch arriving Yellow-browed Warblers or other passerines.
Great Grey shrike BirdTrack reporting rate
Finally, with Hurricane Joaquin veering south-east to Iberia, arrivals of vagrants from North America look less likely now, so the top-tip for this weekend has to be something Siberian/Asian. How about Taiga or Brown Flycatcher?

Paul Stancliffe and Stephen McAvoy

Tuesday 6 October 2015

Yellow-broweds keep on coming!

So far, this autumn has seen the largest arrival of Yellow-browed Warblers for many years, possibly ever! The record day count at any one site in Britain was broken on 21 September, when 53 Yellow-browed Warblers were present on Fair Isle, Shetland. Being on Fair Isle at the time, I was immersed in the experience. It began just after lunchtime when four Yellow-browed Warblers were seen chasing each other on the island’s most southerly beach; as we were watching they were joined by a fifth. A look in the garden behind us produced another three, which were joined by a fourth that seemed to fall out of the sky.

Yellow-browed Warbler by Trevor Codlin

Walking back up the island towards the Bird Observatory during the afternoon, Yellow-browed Warblers seemed to be everywhere, three together on the road; several in the roadside Angelica’s, birds on the walls and fences, and every garden seemed to have one or two – Yellow-browed Warblers were everywhere! The record day count only stood for a short while; a week later 76 Yellow-browed Warblers were counted on the same island.

The last week has seen Redwing and Fieldfare numbers increase, however, the numbers are still small and we might have to wait for easterly winds before we see a large arrival of these birds – it is worth listening out on still nights for the characteristic, high-pitched ‘tseep’ call of these nocturnally migrating thrushes, nocturnal recordings at Portland, Dorset have shown that even though they aren’t being seen during the day, they are passing through at night. At this time of the year any thrush movement will include a few Ring Ouzels and that has definitely been the case in the last few days – October can be a good month to catch up with Ring Ouzel.

Fieldfare by John Harding

Finches have also been on the move. During the last couple of weeks Siskins have been pouring out of their northern English and Scottish breeding forests and heading south in force. Most of this migration has been witnessed inland and on the south coast as they make their way out of the country – it won’t be too long before the first Bramblings of the season begin to appear. Goldfinches are on the move bang on cue, as evidenced by the BirdTrack reporting rate. Even though it seems that many of us have Goldfinches in our gardens all winter, a large percentage still leave the country to spend the winter months in southern Europe and North Africa.

BirdTrack Goldfinch reporting rate

Pink-footed Geese have also been a feature of the last week – flocks have been seen quite frequently as they cross Britain heading for the east coast, with the wind in the west we should see more of this in the next week, along with a few Whooper Swans heading south.

Blackpoll Warbler by Martin Goodey

Now that we are in October and the wind is in the west, any fast tracking Atlantic storm, or deep depression crossing the pond – ex hurricane Joaquin gets here on Friday -  could well bring Nearctic landbird migrants with them. There have already been a couple of Grey-cheeked Thrushes, a Blackpoll Warbler and a Red-eyed Vireo. Every October I think how the occurrence of a Black-billed Cuckoo on mainland Britain is long overdue – the last was seen thirty-five years ago in Cheshire and Wirral, Last year's occurence on North Ronaldsay, Orkney, was typical in that it was in a remote location and only seen on the day it was found. Only three of the twelve birds seen here since 1950 have made it to a second day - another mainland bird would be very well received indeed - maybe this weekend is the one!

Paul Stancliffe