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, 22 April 2016

Spring has sprung, although a little reluctantly

Pretty much all of the long distance migrant species we would have expected to arrive in the UK by mid-April have done just that. But it still feels a little slow and that there are more individuals yet to arrive.

The good weather and associated easterly winds during the week produced some interesting movements of birds. Most notably, Monday and Tuesday produced some good counts of Wheatear at several sites, including 235 on Fair Isle, Shetland and 100+ on Bardsey, Gwynedd. Willow Warblers were also on the move on the same days with 500+ noted on the Isle of Portland, Devon and 200+ at Hengistbury Head, Dorset, with smaller counts at other sites.

Ring Ouzel by Neil Calbrade

After a slow start, Ring Ouzels were noted at many coastal and inland sites during the week, including seven on Bardsey. Spring migration of Ring Ouzel is reaching its peak in the next week or two and the species can turn up in gardens as well as coastal headlands. Listening out for their distinctive call is the best way to find your own Ring Ouzel on your local patch.

Reporting rate of Ring Ouzel on BirdTrack

Pied Flycatchers, Common Redstarts and Grasshopper Warblers were noted in single figures at migration sites along the south and west coast. It was slower going on the east coast, though Linnets seemed to be on the move with flocks of 50 to 100 birds reported.

Swifts have put in an early appearance with individual birds cropping up in several counties, with two birds making it as far north as Yorkshire and Lancashire.

Going up - reporting rate of Swift on BirdTrack this year


Around twenty Cuckoos have also been reported across the country, most from southern counties, but with at least one bird being seen Yorkshire. The first of the BTO's satellite tagged Cuckoos has also made it back safely. Stanley, tagged at Cranwich Heath, Norfolk in May 2014 arrived in Somerset near the town of Chard on the morning of 20 April.

Along the coast, Bar-tailed Godwit and Curlew have been on the move, with Little, Common and Arctic Terns reported as well. It is only a matter of time before Britain and Ireland's rarest seabird, the Roseate Tern, arrives back as well.

Roseate Tern by Stephen McAvoy

Chiffchaff and Blackcap are now being heard across the country but even these two species, for which migration is now getting a little late, still seem a little thin on the ground. It could well be that birds are being held up by weather fronts south in Europe, with the occasional window in the weather letting them through. Perhaps the next flow of warm southerly winds will see a huge arrival of birds all at once.

Unfortunately, the current indication is that northerly winds and cooler conditions will remain in place over the weekend and potentially well into next week. It will be interesting to see how this will impact our recently arrived migrants and residents such as Collared Dove and Robin that are well into raising their first broods in many parts of the country.

Collared Doves by Stephen McAvoy

Finally, we mentioned the beginning of an influx of Alpine Accentors into northern Europe in our last Migration blog update. As luck would have it, one Alpine Accentor did reach our shores with one spotted for all of five minutes in Hampshire on the 14 April. More Alpine Accentors were spotted in out of range areas in France, northern Germany, the Netherlands and two even reached Sweden. 

At the same time, two more species were recorded well out of range. Snowfinches, another high alpine specialist, began to be seen in similar areas to the Alpine Accentors with over 20 birds noted, including one on the island of Heligoland in the North Sea. Switzerland and southern Germany also recorded a very unusual influx of Western Subalpine Warblers in the last week, with more than 20 birds recorded so far. At least two of the latter have also reached Britain (both on Portland) so far this spring.

In the absence of any significant weather patterns in the Alps at the time, it seems likely all three species "overshot" their migration destinations in the southern and central Alps and continued much further north than usual, settling in any suitable habitat.

Paul Stancliffe and Stephen McAvoy

Friday, 8 April 2016

Spring has (sort of) sprung

The warm southerly airflow over the last few days did result in an arrival of summer migrants, with most of the early season birds well represented. However, the floodgates haven't quite opened yet.

Most notable was the first flush of Common Redstarts, Willow Warblers, Blackcaps and Grasshopper Warblers. Whilst quite a few Ospreys are back on their breeding grounds, with one pair at Rutland having already laid their first egg, others continue to arrive along the south coast. The first Reed and Sedge Warblers were also reported. Chiffchaff have arrived back and are well represented on complete lists submitted to BirdTrack.

Reporting rate of Chiffchaff this week on BirdTrack.

Common, Sandwich and Arctic Tern numbers have begun to build a little, and where there are terns, skuas are not far behind. Several south coast seawatches produced dark and light-phase Arctic Skuas.

A handful of early Common Swifts have also been reported, but overshooting southern breeders continue to be thin on the ground. The highlight was a single Woodchat Shrike in Cornwall, as well as a handful of Serin, Hoopoe and Wryneck. One of the latter ringed at Portland Bird Observatory aptly demonstrated the origin of its name.

Common Swift by Dennis Atherton/BTO


Hirundines have continued to arrive and are now being reported from most areas in the country. The first House and Sand Martins have even managed to reach Fair Isle in Shetland during the week.

Outgoing migrants have also taken advantage of the southerly airflow and numbers continue to fall. Brent Geese have been reported heading past east coast watchpoints along with Red-throated Divers and Common Scoters. Several of the latter have been reported from inland sites, including a female on a small lake in central London. Redwings and Fieldfares are beginning to feel decidely thin on the ground.

Reporting rate this year of Redwing on BirdTrack


The forecast for the next few days is currently very mixed, with cool north-westerly winds alternating with milder south-westerly winds. The latter may herald another strong arrival of migrants.

The rare bird to watch for this weekend is Alpine Accentor. It has been recorded only five times in Britain since 2000, with all sightings from the south and east coast. Prior to that, the species has been found in south Wales and even as far north as Fair Isle. Alpine Accentors appear to be on the move at the moment, with several birds recorded well away from their normal range in the montane regions of Europe. This included one flock of twenty birds near Frankfurt since Wednesday, as well as one in the Netherlands.

Paul Stancliffe & Stephen McAvoy

Friday, 1 April 2016

Migration getting started at last


Migration has been slow going until last weekend, but things have noticeably picked up since then with a change in wind direction. Chiffchaff, Wheatear, Sand Martin and Swallow were much more in evidence around the country and the first Reed, Sedge and Willow Warblers arrived.

Pipits were on the move as well. Spurn, Yorkshire recorded 357 Meadow Pipits on 30 March and 300+ moved through Portland, Dorset on the same day. On the west coast, 100+ were counted daily on Bardsey, Gwynedd the past week.

Firecrest by Graham Clarke

The highlight of the week was a big arrival of Firecrests along the south coast, with 101 counted at Dungeness, Kent on the 26 March. This local record tally was beaten just four days later with an amazing 120 Firecrests on site. A handful of other sites reached double-figures and the species was noted at many coastal watchpoints.

Reporting rate of Firecrest on Birdtrack

The south-westerly winds during the week also gave returning winter visitors a helping hand. Brent Geese were noted moving east off Portland, while Redwing and Fieldfare have also been on the move. Surprisingly few Ring Ouzels have been reported so far, but counts should pick up later this month.

There has been a distinct dearth of rarer spring migrants with only a few unconfirmed reports of Alpine Swift. Likely candidates to look for this week include Hoopoe, Woodchat Shrike and potentially a rarer warbler such as Sardinian.

Woodchat Shrike by Stephen McAvoy

The forecast for the next few days shows more southerly winds which would help migrants cross the Channel and the North Sea. However, from the middle of next the week there is a potential return to cool north-westerly winds which could migration on hold again.

Paul Stancliffe and Stephen McAvoy

Thursday, 24 March 2016

The floodgates are ajar

The cold northerly airflow has been holding things up during the last week but with lighter winds during the last couple of days some birds have managed to get through.

Several sites along the south coast have enjoyed double figure arrivals of Wheatear. Portland, Dorset seems to have seen the best of this with 60 being counted there on the morning of 22 March. Sand Martins have continued to trickle in but numbers remain small, similarly Swallows have been arriving but are still very thin on the ground, and one or two more House Martins have also been seen.

 
Sand Martin reports via BirdTrack

Garganey arrived in small numbers but on a broad front with birds being reported from several counties during the week. The largest movements seen this week involved Meadow Pipits arriving and then moving along the south coast. Several hundred birds were noted moving through on a couple of days.

Late arriving: Wheatear

As one set of birds arrives, another set is departing. Redwing and Fieldfare have been recorded, at times in quite large flocks, as were flocks of migrating Starling. Geese were on the move as well, with northward bound Pink-footed Geese amongst others noted in Scotland. Woodcock were found at several coastal sites.

Redwing moving through

The most intriguing migrant this week was probably the Blue Tit trapped at Sandwich Bay Bird Observatory. It was found to have been ringed in Lithuania and had good muscle and fat scores, presumably to fuel the outgoing migration back north and east. Keep an eye on the BTO's Demog blog on this and other ringing related stories.

The Met Office surface pressure charts show potential for some south to south west winds extending from northern Spain across France to southern Britain from Friday onwards. This ought to result in a fresh wave of arrivals from the south, and allow any migrants wanting to attempt the crossing of the North Sea to have a go.

Likely new arrivals next week include the first Willow Warblers and Blackcaps, as well as more Wheatears and Sand Martins. Given the stormy weather conditions, there may even be local "falls" of migrants. Rarer migrants to keep an eye out for in late March and early April include Purple Heron, Alpine Swift and the even rarer Great Spotted Cuckoo!


Purple Heron (Graham Catley)

 Paul Stancliffe and Stephen McAvoy

Friday, 18 March 2016

Migration blocked

The high-pressure that is currently sitting over most of the British Isles is producing fronts along its flanks and a predominantly north-easterly airflow that is pretty much blocking migration from further south. The relatively light winds, at times, have let a few migrants through but it has very much been a trickle, not a flood.

Sand Martins, Wheatears and Chiffchaffs have arrived in small numbers and there has been one or two Swallows arriving with them but even with this arrival things are very slow. Looking at the weather charts for the next few days it looks like things aren’t likely to change very much.

Chiffchaff by Amy Lewis

All of the BTO satellite tagged Cuckoos have now left the Congo rainforest, four are in West Africa and three are in the Central African Republic. We expect the first of them to cross the Sahara in the next week or two.

Blackbird by Jez Blackburn

Going north, birds have definitely been on the move. The number of Whooper and Bewick’s Swans are falling rapidly, Pink-footed Geese have been seen over the Pennines in good numbers, and ringers have seen long-winged Blackbirds with high fat scores in gardens in the east, birds that could be crossing the North Sea any day now.



Although the forecast isn’t looking too promising there will be a period of light east, north-east winds over the Channel on Sunday/Monday, and they might just be light enough to allow any birds that are held up further south to move. If this is the case, it will be more Sand Martins, Wheatears and Chiffchaffs, with maybe a few Ring Ouzels, Garganey and Swallows thrown in.

Thursday, 10 March 2016

Kittiwakes moving through

The cold northerly and westerly winds during the last week or so have pretty much put the brakes on the arrival of any early summer migrants. However, a small number of hardy individuals did make it here. At least three Sand Martins have been seen in the last week - the first at Frampton-on-Severn, Gloucestershire on the 5th March followed by further singles in Glamorgan, West Midlands and Carmarthen. An Osprey was notedin Cheshire, two Stone Curlews back on their heath in Suffolk, and a handful of Wheatears were reported from scattered sites in the south.

Wheatear (Moss Taylor)


Much further south, House Martins, Swallows and the first Pallid Swifts are back on their breeding territories in southern Spain. Black Kites and Short-toed Eagles have been seen leaving North Africa and crossing the Straits of Gibraltar. The BTO-tagged Cuckoos are also moving on from their winter territories and are beginning to head north to make the perilous journey across the Sahara. Spring is coming.

A feature of the last week has been the surprising number of Kittiwakes spotted at inland sites across central and southern England. The majority of records involved single birds on larger lakes and reservoirs, but three were noted at Calvert Lakes in Bucks and two even visited the BTO's Nunnery Lakes reserve on the 3rd March. The day before 150 had been seen from Severn Beach, Gloucestershire. Could these birds (and more) have followed the Severn upstream and then moved broadly east towards the North Sea?

Kittiwake on the Nunnery Lakes (Stephen McAvoy)

Although the weather might have stalled spring migration so far, it looks like there may be a change on the cards over the weekend and early next week with some southerly winds forecast. It is still early in the season, so the floodgates aren't likely to open just yet. A few more Chiffchaff, Wheatear and Sand Martin should arrive, along with perhaps the odd Swallow.

Paul Stancliffe & Stephen McAvoy

Friday, 5 February 2016

Storm driven birds

After a short cold spell in mid to late January, which brought frost and some snow to most areas, Atlantic weather patterns have reasserted themselves. A procession of storms has affected Britain and temperatures have reached double figures again. It feels much more like autumn than winter.

At this time of year many birds are settled on a winter site, with the largest movements undertaken being those from roosting site to feeding site. However, the storms have stirred a few birds up. Here in Thetford, Norfolk, there has been an obvious passage of Common Gulls during the last couple of days, presumably storm driven birds. There have also been several records of Kittiwakes in inland counties, including Surrey and Northamptonshire.

Kittiwake by Edwyn Anderton


In general, it has been a very good winter for gulls, with more than 20 species recorded, including the likes of Ross's Gull and Glaucous-winged Gull. It has also been a good winter for Caspian Gulls, with the reporting rate on BirdTrack well above average so far. The two large "white-winged" gulls, Iceland and Glaucous Gull, have also been noted on more complete lists submitted to BirdTrack in 2016. 


Reporting rate of Caspian Gull on BirdTrack
 
Intriguingly, two Franklin's Gulls have been found in our area in the last ten days. The species winters in the Caribbean and South America and is only rarely recorded north of Florida in winter. Have "our" two Franklin's Gull been swept across the Atlantic by one of the recent storms or have they been hiding unseen in gull flocks since the autumn and only now been discovered by birders?

The stormy conditions appear to have displaced divers in the North Sea, with some good counts of Red-throated Divers passing Spurn, East Yorks. Auks, mainly Guillemots have also been a feature, passing sites along the west coast in good numbers. Presumably, when conditions ease many of these birds will begin to make their way to their breeding colonies, but for now riding out these storms seems to be the order of the day.

Looking ahead, a further storm may affect the south coast of Britain on Monday, potentially bringing some more seabirds to inshore areas.


Paul Stancliffe and Stephen McAvoy