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.

Thursday, 19 April 2018

Stop, start migration

This spring has been a very interesting one, so far. For the first few weeks it was definitely running late. Chiffchaff, Blackcap, Sand Martin and other early migrants were 2-3 weeks behind their normal migration pattern. Fast forward to the here and now and it is hard to believe migration is late at all. Those birds that should be arriving right now, including Cuckoo, Nightingale and Hobby, are arriving bang on cue.  In northern Britain some species have arrived early. In the last few days, Fair Isle has had its earliest ever Lesser Whitethroat and Dotterel.

Dotterel by Edmund Fellowes

This all goes to show how weather affects our long-distance migrants and how spring migration is a bit of a lottery; arrive here early and in an early spring the gamble may well pay off, this year it probably hasn’t; arrive here late and you might miss the best breeding territories and the strongest mate, this year you might be OK.

With southerly winds some of our early migrants have caught up and pretty much seem to be back on track, as seen in the BirdTrack Chiffchaff graph below. But what has happened to Wheatears? They are still way behind where they should be for this time of the year; check out its BirdTrack graph. It’s getting to the stage where we might consider something more sinister at play rather than just being delayed. Might there have been a problem in the winter quarters?

Chiffchaff BirdTrack reporting rate

Wheatear BirdTrack reporting rate

The forecast for the next few days is for south and south westerly winds, which will be particularly light over southern and central Europe. This should really open the floodgates for our migrants, both those making their way here and for those leaving. I still have Bramblings in my garden but probably won’t have by the weekend.

Brambling by John Harding

So, if you haven’t already heard a Cuckoo you could well do over the weekend, two of our satellite tagged birds are back, you can find more about them here. Keep an eye out for Hobby, and even an early Swift or two. Amongst these many of our migrants will become more obvious, Reed Warblers, Grasshopper Warblers, Whitethroats and Garden Warblers should all be seen and heard over the next few days. Tern passage will start to build too, with Common, Arctic and Sandwich Terns all on the move.

Black Kite by Jill Pakenham

With lots of birds on the move there is bound to be a few overshoots with them, the most obvious are Hoopoe, Purple Heron, Black Kite and Red-rumped Swallow, but we could also see one or two Sub-alpine Warblers and hopefully Alpine Accentor, one that hangs around for a couple of days allowing lots of birders to catch-up with it.
Paul Stancliffe

Thursday, 12 April 2018

Migration still slow

During the last week there has been an arrival of summer migrants, with most of the early arrivals represented. However, numbers still seem to be quite low. Although spring feels late this year the first Sedge Warblers have arrived bang on cue and Ring Ouzel has pretty much caught up.

BirdTrack reporting rate for Ring Ouzel

With that in mind it will be interesting to see how the next week unfolds. There is a good window in the weather on Friday going into Saturday when winds will be easterly turning southerly and light across the Channel and the southern North Sea. This should allow anything held up to move, at least those birds that have made it north of the Pyrenees. It looks like there will be a blocking weather front just north of the mountains that will probably stop any birds moving in to it in their tracks.

Pied Flycatcher by John Harding

So, what might turn up? Pied Flycatchers, Redstarts and more Ring Ouzels should definitely be a feature; in fact it might well be a Ring Ouzel weekend. We should see more Black Redstarts too and possibly one or two more White-spotted Bluethroats.

Cuckoos seem to pretty much on time too but if you haven’t heard one yet you could well do at the weekend. With any luck we should have our first satellite tagged bird back too, the closest is just over three hundred miles south of his Suffolk territory, so he might well make his move on Friday. You can follow him and four other tagged Cuckoos here.

Whitethroat by Amy Lewis

Right now we should be seeing Whitethroats, Willow Warblers, Yellow Wagtails and Tree Pipits either moving through or singing on territory; this could well be the case on Saturday morning. White Wagtail and Little Gull are classic birds for this time of the year in these conditions too.

Wryneck by Jill Pakenham

With easterlies forecast it is worth keeping an eye out for a Wryneck or two, especially if you plan on visiting the east coast, and who knows? We might be treated to a Pallid Swift too.

Friday, 6 April 2018

Migrants about to flood in

Spring migration has been a bit of a trickle so far, however, this is about to change. The forecast for the next few days, and into next week, is one of southerly and at times fairly light winds, the ideal recipe for migrants that have been held-up to finally arrive.

Chiffchaffs and Blackcaps should really be here in force now but as evidenced by the BirdTrack graphs they are running about two weeks late.

These aren’t the only birds running late as most of the early migrants seem to be held-up further south. The graphs for Swallow and Wheatear are just as revealing.

As we write this, birds are at last beginning to arrive, several Chiffchaffs and a single Willow Warbler are now singing on the BTO’s Nunnery Lakes, and the first singing Blackcap of the spring has just burst into song at the headquarters.

The winds on Friday are forecast to be coming from as far south as North Africa, which will almost certainly provide a window for some of our later arriving visitors to get here a little early; there is already a report of a Common Swift from Lancashire and the winds are only just turning south. During the next couple of days birds such as Cuckoo, Turtle Dove and Hobby should all be on the cards. The trickle of Yellow Wagtails, Tree Pipits and Ring Ouzels should also grow, and we should see the first push of Sedge Warblers.

With winds coming from so far south, overshoots will be inevitable, Alpine Swift, Hoopoe, Red-rumped Swallow and Black Kite are the classics but a showy Great Spotted Cuckoo would be much appreciated.

A flavour of migration further south has been given to us a by a friend who is currently working on a survey ship 8 miles off the North African coast around Agadir, Morocco. He has seen flocks of Pintail heading north, a trickle of Sandwich and Common Terns accompanied by Arctic, Long-tailed and Pomarine Skuas. 

Long-tailed Skua chasing Sandwich Tern
 by Andrew Williams

Swallows have also been on the move but the highlights have included Grey Phalaropes, a Hoopoe being mobbed by several gulls that managed to run the gauntlet and carry on north, and a Purple Heron that tried to land on the ship but failed and too continued north.

 Hoopoe off Agadir by Andrew Williams

Evading capture

Paul Stancliffe
Scott Mayson

Thursday, 15 February 2018

Finches on the move?

The last week has seen the number of Chaffinches, Goldfinches and Siskins build in a few BTO staff member’s gardens here in Thetford. It has been a very quiet winter for all three so we are almost certainly experiencing a movement of these birds through the area. Presumably these are birds that have been wintering south and west of here and are moving north and east in preparation for the forthcoming breeding season. The BirdTrack graphs for Chaffinch and Goldfinch show the upturn of both species well. It is interesting to note that Chaffinch is well below its historical average, probably as a result of fewer birds crossing the North Sea last autumn.

All of the satellite tagged Cuckoos that we are currently following have made a move north; Selborne currently leads the pack and has moved further west in the last couple of days into Guinea. In 2017 he crossed the Sahara on 25 March, having arrived in West Africa on 2 February. It is fascinating to think that along with the Cuckoos many of our summer migrants will already be on their way back too. House Martin and Swallow have already been recorded in southern Europe.
Follow the Cuckoos here as they make their way back.

Closer to home, Red-throated Divers are on the move, with double figure counts past several coastal watchpoints and Wigeon numbers are also beginning to build at east coast sites.

Red-throated Diver by Andy Mason

With lots of birds redistributing around the country now is a great time to look for rarer geese amongst the flocks of commoner species. Flocks of Pink-footed Geese are worth checking for Tundra Bean, and Red-breasted Geese have been known to associate with them too.

Iceland Gull by Scott Mayson

White winged gulls are also on the cards as they too begin to move back north, Iceland and Glaucous Gulls can turn up almost anywhere at this time.

Scott Mayson and Paul Stancliffe

Tuesday, 30 January 2018

Migration underway

It might only be the end of January and the days might still be short but some of our birds have already begun their spring migration. Fieldfare and Redwing have started moving north and east, with numbers beginning to build in eastern Britain. Siskins have started to turn up at garden feeding stations as they too make their way back north, and the first of the BTO satellite-tagged Cuckoos has begun the long journey back to the UK.

Cuckoo PJ spent most of the winter in Angola but since leaving there last week he has travelled 1,600 km (1,000 miles) north and is now in Cameroon. He should head west from here before once again turning north and crossing the mighty Sahara. You can follow him as he makes his way back home during the next couple of months.

Auks are also on the move and Guillemots and Razorbills could be back prospecting on their breeding ledges any day now. Look out for them at coastal watch points.

Guillemot by Sarah Kelman

One of the biggest surprises of the autumn 2017 migration was the unprecedented arrival of Hawfinches into Britain. The exact number is difficult to calculate as the birds are so widespread and mobile, but it is thought in excess of 1,000 birds have arrived here and that the true figure might even be as high as 5,000. The estimated breeding population is only 500 – 1,000 pairs, so this is an incredible increase. The BirdTrack graph shows how spectacular this arrival was compared to the historical average for the species, and they are still being seen across the UK. Some of the largest concentrations are currently to be found in Surrey, Sussex and Shropshire.

Hawfinch BirdTrack reporting rate 2017 almost quadrupled

It’s only a matter of time before the wintering geese and wildfowl begin to head north and east too. February is the peak month for Pintail, Goldeneye and White-fronted Goose all of which will be steadily heading to the breeding grounds in Northern and Eastern Europe. Male Goldeneyes at this time of the year can often be seen performing their display which involves throwing their heads backwards, then forwards – extending the neck as they do so – in readiness for the breeding season ahead. Other wildfowl will be getting in to flocks ready to depart when the weather is favourable, with some heading across Europe whilst others,such as Whooper Swans and Pink-footed Geese, will be heading to Iceland and Greenland for the summer months.

Scott Mayson, BirdTrack Organiser, and Paul Stancliffe, Media Manager

Friday, 27 October 2017

Hawfinches galore!

The incredible numbers of Hawfinches across southern England has dominated the migration picture this week, with thousands of birds thought to be involved and there does not appear to be any let up.  Many areas where Hawfinch would be a rare bird if a single bird appeared have seen staggering numbers, with the largest count being 115 over Steps Hill in Buckinghamshire on a single morning.

Hawfinch by Chris Knights

Possibly the most unusual record this week was a Razorbill about as far inland as it is possible for a seabird to turn up, at Draycote Water in Warwickshire, but unfortunately it was found dead the following day.

Despite a continuation of westerly winds in many areas this week, few new vagrants from North America were found, though Blackpoll Warbler on North Uist, Grey-cheeked Thrushes in Co.Cork and on Scilly, and a fly-through Cliff Swallow at Spurn Point were seen. 

Rare birds from the east as a result have been relatively few with Pallid Swift at Spurn and it or another further up the Yorkshire coast and a Black-throated Thrush on Fair Isle being the highlights.  A scattering of Dusky and Radde’s Warblers, Olive-backed Pipit and Little Buntings were found too, fairly typical birds seen at this time of the year.

Brambling by Allan Drewitt
A brief switch to much colder northerly winds this weekend will see further arrivals of Redwings and Fieldfares along with Song Thrushes and Blackbirds and finches, in particular Chaffinches and Bramblings from Scandinavia.  Wildfowl too will be on the move with more Pink-footed, Barnacle and Brent Geese and Whooper Swans arriving from their arctic breeding grounds to spend the winter in the UK. The first Little Auks of the autumn may appear, mostly in Scotland, though some may penetrate into the North Sea down the east coast of England as far as Norfolk or Suffolk.

Brent Goose by John Harding
After the brief spell of northerly winds over the weekend, westerly winds are again set to dominate next week which may curtail the arrival of many traditional migrants, though we could see further American vagrants – American Robin and Rose-breasted Grosbeak are often among the later autumn vagrants found. 

- Neil Calbrade

Friday, 20 October 2017

Bird, birds and more birds!

It seems that birds from all points of the compass have been arriving in Britain during the last week. Unsurprisingly, given the westerly storms, several species of North America landbirds were found. A White-crowned Sparrow, one each of Swainson’s and Grey Cheeked Thrushes, singles of Yellow-billed Cuckoo and Blackpoll Warbler and two Red-eyed Vireos graced our shores.

Even though westerlies have dominated the weather, a small window of northeasterly at the beginning of the week and lighter winds during the last few days have meant that birds from the east were able to cross the North Sea, most notably thrushes. Many of us will have enjoyed the first significant arrival of Redwings, along with a few Fieldfares. Accompanying these have been arrivals of Blackbirds, Song Thrushes and a few Ring Ouzels. Finches have also been on the move, most notably Chaffinches, Siskins and Hawfinches.
Hawfinch by Edmund Fellowes

On the eastern scarcity/rarity front, there have been up to ten Red-breasted Flycatchers, half-a-dozen Barred Warblers, a handful of Red-backed Shrikes and Radde’s Warblers, three Blyth’s Reed Warblers and a couple of Olive-backed Pipits and Dusky Warblers, not forgetting the first two Pallas’s Warblers of the season.

Red-breasted Flycatcher by Graham Catley

Northerly winds mid-week saw the arrival of Whooper Swans, and Pink-footed, Greylag, Barnacle and Brent Geese. More notable though was the arrival of eight Blue Tits on Fair Isle! British Blue Tits don’t move very far at all but Scandinavian birders often experience spectacular southerly movements of Blue Tits evacuating the cooling north. Presumably the eight on Fair Isle were part of this phenomenon.

The south wasn’t left out this week either. The influx of Firecrests has continued and up to three Hoopoes and at least one Bee-eater were found.

Firecrest by Graham Clarke

Westerlies are set to dominate for at least the weekend but Monday will see south-easterlies out of southern Scandinavia. So, we can expect one or two more North American landbirds to be found in the west and south-west over the weekend, with birds crossing the North Sea during the early part of the week. Northern Britain and the northern isles look likely to receive the lion’s share but the east coast should see some action too. More thrushes should arrive, in particular Redwings but with increasing numbers of Fieldfare, and finches should move too, in particular Brambling. We could see one or two more Red-eyed Vireos and maybe something a little rarer, possibly Hermit Thrush from the west over the weekend, and more Dusky and Pallas’s Warblers from the east into next week.

Paul Stancliffe