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, 11 November 2016

Birds still on the move

We are nearing mid-November, a time when you begin to feel that autumn migration has pretty much come to a close, and, while that may be the case for some species, it still feels like this autumn has more to give.

Waxwings have been on the move all week with new flocks noted on the east coast. Smaller flocks have so far been noted further inland, but numbers should continue to build in the coming weeks and Waxwings should reach most parts of the country. There may be further arrivals from the Continent as berry crops run low.

Waxwings by Jeff Baker/BTO


Reporting rate of Waxwing on BirdTrack

Another feature of the week has been the number of inland waterbodies that have hosted Scaup. Like Waxwing, the current reporting rate is well above average suggesting a wider arrival, perhaps as suitable waterbodies became scarce in last weeks cold snap in Scandinavia. Perhaps Smew could follow suit.

Drake Scaup by John Proudlock/BTO


Reporting rate of Scaup on BirdTrack

One of the better spectacles of the late autumn and early winter so far has to be arrival of Shorelark. Up to 100 birds have been seen at Holkham in North Norfolk in the last few weeks, with smaller flocks elsewhere along the east coast. A few have reached further afield, including singles on Anglesey and Hampshire.

The last of the summer visitors are still trickling through, the mega-rare Cliff Swallow at Minsmere, Suffolk last weekend shared the sky with eight Swallows and a very late Sand Martin. There has also been a flurry of Ring Ouzel records during the last week.

Predictably for the east coast, the easterly and north-easterly winds brought Little Auks with up to 14 recorded at seawatching sites. Long-tailed Duck and Velvet Scoters were also logged at many spots, as well as the more expected Great and Pomarine Skuas.

Little Auk by Morris Rendall/BTO


For the weekend and beyond the weather looks to be dominated by westerly winds originating from north-eastern Canada. There is a small chance of some late Nearctic rarity turning up on a remote headland in Ireland or Scotland and Mourning Dove, Yellow-rumped or Blackpoll Warbler being typical November arrivals. Commoner birds that will continue to arrive include Starling and Blackbird from Scandinavia and beyond, and keep an eye out for Woodcock which reaches peak reporting rate in BirdTrack in late November.


Paul Stancliffe and Stephen McAvoy

Monday, 24 October 2016

Still plenty of eastern promise

The low pressure system that crossed the UK during the latter part of this week looked like it might bring the run of easterlies to an end. However, with the high-pressure system forecast to linger over Scandinavia, the easterly winds will feature in the middle of this week at least.

A brief dally with westerly winds during mid-week produced some spectacular seabird movements along the west coast that included 2,433 Razorbills, 4,068 Kittiwakes, 898 Gannets, along with a few Arctic, Great and Pomarine Skuas past Bardsey, Gwynedd, on 18 October.

Kittiwakes by Martin Cade


As would be expected at this time of year, finches are still on the move, with Linnets and Goldfinches predominating. The first real movement of redpolls, Mealy and Lesser pretty much in equal parts, have also been a feature of the week, along with Brambling and to a lesser extent Chaffinches and Siskin.


Thrushes continue to pile in, although mainly Redwing and Fieldfare, we might have to wait until next week for Blackbirds to arrive in force.

The highlight of the week has been the arrival of several flocks of Tundra Bean Geese, in higher numbers than we would normally see and a little earlier too. Shorelark, another scarce Scandinavian winter visitor, have equally been noted in above average figures for recent years. Flocks of 28 of the latter have been noted in Lincolnshire and Norfolk for example.

Shorelark reporting rate on BirdTrack


Swallows and Wheatears continue to trickle south, but House Martin observations have fallen dramatically, with most birds now probably on their way to as yet unknown winter quarters.

Following on from sightings in Shetland and Yorkshire, several more Siberian Accentors were spotted in Britain. The bird in Easington, East Yorkshire drew large numbers of admirers with several thousand birders making the journey in the course of the Accentor's seven day stay.

The Easington Siberian Accentor by Andy Mason

Associated with the Siberian Accentors was a notable arrival of rare warblers and wheatears, in particular Dusky Warbler and Isabelline Wheatear. No less than seven Dusky Warblers were found at Spurn, East Yorkshire last week and five Isabelline Wheatears represent an above average return from a species seen only on 30 previous occasions in Britain and Ireland.


Reporting rate of Dusky Warbler on BirdTrack


After peaking at almost 8% of BirdTrack complete lists in early October, reports of Yellow-browed Warbler has dropped off in the last week and were logged on only 4% of lists this week. The equally diminutive Pallas's Warbler has partially filled this gap, being noted on just over 1% of complete lists.

Waxwing by Andy Mason

Finally, Waxwings are on the move across the North Sea, with small flocks reported from all along the east coast of Britain. Will this year see a repeat of the last good Waxwing winter in 2012/13?

Paul Stancliffe and Stephen McAvoy

Friday, 30 September 2016

East meets West

It has been an exciting week with new arrivals from the east and west this week. Top billing goes to the Eastern Kingbird found on Barra in the Outer Hebrides on Thursday. This large flycatcher is a widespread breeding bird in Canada and the US and has been previously found twice in Ireland following sustained westerly winds. The Kingbird joined an impressive cast of birds from North America found during the week: two Swainson's Thrushes, four Red-eyed Vireos and singles of Yellow-billed Cuckoo and Rose-breasted Grosbeak.


Red-eyed Vireo by Luke Delve

Arriving from the opposite direction, birds of Scandinavian and Siberian origin continued to arrive despite the prevailing westerly winds. The Yellow-browed Warbler invasion slowed to a trickle, with only single figure counts from coastal watchpoints. However, a few more were noted away from the coast, including one at the BTO's Nunnery Lakes reserve.

Yellow-browed Warbler at the Nunnery Lakes by Neil Calbrade

In terms of more widespread migrants, 1,450 Swallows passed Christchurch Harbour, Dorset during the week and there were counts of several hundred birds from other migration watchpoints. While a handful of House Martins are still feeding young in nests, the majority are on the move south and over 1,000 were counted moving past Filey, East Yorkshire. Pink-footed Geese arrived in numbers this week and the count of 2,000+ passing Spurn, East Yorkshire was the highest noted on the east coast this week. Several sites reported increased numbers of Goldcrest and the species should reach a peak later next month.

Reporting rate of Goldcrest on BirdTrack


All but one of the active tagged BTO Cuckoos have crossed the Sahara and are currently spread between Niger and Chad. Cuckoo "Larry" has jumped ahead of the rest and has reached the Republic of Congo. As of this morning, Cuckoo "Jack" is still in southernmost Italy, but looks set to make the perilous crossing any day soon.

Current location of the BTO-tagged Cuckoos

The south-westerly airflow looks likely to remain in place over western Britain and Ireland into early next week and could well drop another North American rarity or two onto western headlands. A weak low pressure system moving through the Channel on Saturday could bring some north-easterly winds to eastern Britain for Sunday and Monday. This could result in another wave of Yellow-browed Warblers arriving here, as well as winter thrushes. Surprisingly few Ring Ouzels have been reported so far this autumn so that is one bird to look for this weekend on the east coast.

One to look for this weekend - Ring Ouzel by John Proudlock/BTO

Rarer passerines may also make an appearance, and such after species as White's Thrush, Red-flanked Bluetail and Red-throated Pipit all having a track record of making appearance at this time of year. All this makes for an interesting mix of birds on the move and well worth going out no matter which part of the country you are in.

Stephen McAvoy

Friday, 23 September 2016

Yellow-browed Warbler Invasion

The migration story of the week was the remarkable arrival of Yellow-browed Warblers on Flamborough Head, East Yorkshire on Wednesday, with a minimum of 139 recorded during the day. A narrow band of north-easterly wind across the North Sea appears to have funnelled the warblers onto the headland of Flamborough.


There have been plenty of reports elsewhere in Britain, though for the moment, the majority are being noted along the east coast of Britain. In the weeks ahead, the birds should begin to filter south and west, and with more records inland in recent years, there is a chance you may find one on your patch even if you are not near a prime coastal migration site.

Yellow-browed Warbler by Stephen McAvoy

The arrival of Yellow-browed Warblers in the last few days is also reflected on the reporting rate on BirdTrack:


Commoner migrants have also been on the move, with Pink-footed and Brent Geese beginning to arrive in numbers. Meadow Pipits continue to move through, with over 1,000 logged at Christchurch Harbour, Dorset on Wednesday, and 1,200+ at Sandwich Bay, Kent on Monday. Several sites also reported good 100+ counts of Blackcap and Chiffchaff during the week. The 484 Snipe recorded on North Ronaldsay, Orkney on Thursday would have also made a very interesting sight!

Snipe by Liz Cutting/BTO

Looking ahead, the weather looks set to be dominated by westerly airflow, so there is a chance a Nearctic warbler or vireo could make an appearance on a headland or island in Ireland or western Britain. The first Ring Ouzels should also start to arrive at migration points fairly soon, as should the first returning Redwing and Fieldfare.

Ring Ouzel by Paul Hillion/BTO

Paul Stancliffe and Stephen McAvoy

Friday, 16 September 2016

Arrivals and Departures

Bird migration is in full swing as we move into late September and there were some notable counts of some commoner migrants this week despite the generally poor conditions for finding birds.

Wheatear by Mark Johnson (via #Birdtrack Flickrpool)


The obvious migration highlight of the week was the (very lost) Cory's Shearwater seen flying over Regent's Park in London during the week. Small numbers of shearwaters are recorded at inland locations in late summer and early autumn, in many cases recently fledged youngsters that have become disorientated. Large shearwaters such as Cory's or Great are significantly rarer inland and are usually found in the aftermath of particularly strong storms.


Lapland Bunting by Janice Sutton (via #BirdTrack Flickrpool)

Notable scarcer migrants on the move included Lapland Bunting, with up flocks of up to 90 birds reported from western Scotland and Ireland in recent days. A handful have also been reported in southern Britain so it is well worth listening out for their distinctive calls when out and about. The first Yellow-browed Warblers of the autumn have also arrived, hopefully heralding yet another bumper year of these charming Siberian sprites.

Yellow-browed Warbler by Stephen McAvoy


Significant counts of commoner migrants included 3,500 Swallows noted passing Christchurch Harbour, Dorset on the 14th September and just under 3,000 at Skomer, Pembrokeshire on the same day. Fair Isle, Shetland logged 232 Wheatears on the same day, with 150 Wheatears counted on Portland, Dorset the next day.

The Migration Festival at Spurn, East Yorkshire ended with a fantastic movement of over 4000 Meadow Pipits passing through on the Sunday, though the highlight of the weekend was undoubtedly the Kentish Plover found the previous day. A worthwhile event for anyone with an interest in bird migration so keep a space in your diary for MigFest 2017!

Stephen McAvoy

Monday, 11 July 2016

Early movers

Although autumn is still some way off, migration is already in full swing with Cuckoo, seabirds and waders amongst others on the move. All of the BTO GPS-tagged Cuckoos have moved south and out of Britain. One of the tagged birds has already crossed the Sahara and is now in central Mali. The BirdTrack graph shows the drop off in recent records.

Reporting rate for Cuckoo

Juvenile Cuckoos will still be present into August and September before they too will depart to their winter quarters.

Cuckoo by Neil Calbrade

Seabirds are also on the move with the first Great and Cory's Shearwaters reported from seawatching sites in southern Britain and Ireland. Breeding in the South Atlantic, Great Shearwaters migrate north in spring (their autumn), spending the early summer off the east coast of North America. In July and August, they head south again, but on a more easterly track, passing western Europe and Africa. Strong winds, especially from the west or south-west, can push these highly oceanic birds closer to land, sometimes in spectacular numbers.

Great Shearwaters by Hannah Keogh (via the #Birdtrack Flickrpool)

Further coastal birds on the move included Arctic and Great Skuas, while small flocks of Common Scoters were noted passing coastal watchpoints in the last week. Looking ahead, the weather forecast is mainly for westerly winds and showers, conditions that look quite suitable for pushing skuas, shearwaters and other seabirds closer to shore.


Migrant gulls have also started arriving, including the first juvenile Yellow-legged and Mediterranean Gulls. One of the latter on Fair Isle last week was only the second record for this remote island.

Mediterranean Gull by Stephen McAvoy

While the long-staying Great Knot in Norfolk got a lot of attention, other waders have been on the move. Green and Wood Sandpipers have been arriving, and a flock of 100 Curlews flew south past Landguard Bird Obs, Suffolk. Numbers of other arctic breeding waders will continue to build as adults and the first juveniles arrive in the coming weeks.

Finally, the first migrant Wheatear, Whinchat and Common Redstarts have been reported and 228 Sand Martins were seen moving south at Spurn, East Yorkshire on the 4th of July.

Paul Stancliffe and Stephen McAvoy

Friday, 20 May 2016

What an amazing week

Calandra Lark by John Harding

If rare birds are what makes you tick, the last week or so has to be one of the best spring periods on record. Last week’s Caspian Stonechat, Calandra Lark and Dalmatian Pelican (if accepted as a wild bird) would take some beating and it would take a very special trio of birds indeed. However, Britain’s second ever Green Warbler, found on Shetland, Britain’s first ever spring Blyth’s Pipit and the first ever Lammergeier (if accepted as a wild bird) seems to have done the trick.
But what of our common migrants?

The week has seen a rush of hirundine passage, particularly through a few south coast watchpoints. During the morning of 19 May sample counts at Portland, Dorset suggested that Swallows were passing at a rate of 550 per hour. It is interesting to note though that the BirdTrack reporting rate for House Martin is behind the historic reporting rate, so we might have a large arrival of House Martins still to come.

House Martin BirdTrack reporting rate 

Spotted Flycatcher migration seems to have stalled in the cooler northerly airflow that we have been experiencing. There might be a window in the weather after early rain on Sunday morning when fairly calm conditions are forecast on either side of the English Channel, but by early next week we will be back in northerly airflow again.

The forecast for northern Britain is a mixed bag with the early part of the week looking quite stormy at times. This could be good news for anyone heading north to catch up with Long-tailed Skuas, as the birds could be pushed close to the northern isles, they will almost certainly be accompanied by Pomarine Skuas too.

Nightjar by Neil Calbrade

Any still, clear conditions during the next week will also help any Nightjars that are on the move. Some birds are already back at their breeding sites but the BirdTrack reporting rate shows they will continue to arrive during the next couple of weeks. And of course, waders will continue to push north when conditions allow too. Wood Sandpiper and Temminck’s Stint are good mid to late May birds to look out for.

Nightjar BirdTrack reporting rate