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 May 2015

Migration slowing down – or is it?

The weather has been such a mixed bag during the last couple of weeks it has been difficult to disentangle and work out what effect it has had on migrant birds. The almost autumn-like westerly fronts that have been tracking across the Atlantic do seem to have brought some Nearctic birds with them – Great Blue Heron, Hudsonian Godwit and Dark-eyed Junco are all incredible spring birds.

As the fronts have passed over Britain they have introduced sporadic southerly and south-easterly airflow, which at times has been quite productive. Spring 2015 will go down as a ‘southern herons’ spring, particularly in the south-west. If you were on the Isles of Scilly last week it was possible to see up to five Night Herons, two Little Bitterns, a Squacco Heron and a Purple Heron! It must have felt a little like being in southern Europe.

Squacco Heron by Derek Belsey

So, migration has continued apace but there are signs that it is slowing down; counts at coastal watchpoints are returning diminishing numbers. However, it does seem like some of the common migrants are still a little thin on the ground and that there are still plenty more to arrive. Perhaps we are in need of some warm southerly winds to test this out. Certainly here in East Anglia there seems to be fewer Cuckoos than were around last year and the BirdTrack reporting rate seems to reflect this nationally. Willow Warbler and Whitethroat are showing similar reporting rates, and if Spotted Flycatcher is to get anywhere near the BirdTrack historical reporting rate there are a lot more to arrive yet.

BirdTrack reporting rate for Cuckoo

Skuas have been on the move past the Outer Hebrides during the last couple of weeks; the highest count has been of 1,307 Long-tailed Skuas flying past  Aird an Runair, North Uist on 12 May, and accompanied by 353 Pomarine Skuas must have been an amazing sight.

Pomarine Skua by Joe Pender

Quail have begun to turn-up in small numbers. These enigmatic little birds can be quite common in some years and almost absent in others. As Quail can still turn up in early June, it is still a little too early to tell whether this will be a Quail year, or not.

So, what might we expect this weekend? Initially it looks like we will have light northerly winds at least on Saturday into Sunday morning, and again on Monday. At this time of the year these conditions can be quite productive. Migrants birds can and do migrate into light northerlies and if there is going to be a late push, Saturday and Sunday morning look good. On the rarity front, something from the south east is always on the cards this late in May – Red-footed Falcon is the obvious candidate but a spring male White-throated Robin would really set pulses racing.

Friday, 24 April 2015

Migration in full swing – almost

Migrants have been piling in during the last week – Willow Warbler counts have reached three figures on several days at south coast watchpoints, there have been small flocks of Ring Ouzels on the east coast and Cuckoos have reached Scotland but it still feels like many of our summer visitors are still thin on the ground. Where are all the Sand Martins? And there really ought to be more Lesser Whitethroats than there are. The next week or so should unveil whether some birds are just held up further south or whether they had a bad winter.

BirdTrack reporting rate for Sand Martin

Even though some species feel a little low in numbers most species are now here. There have been one or two Nightjars during the week, Swift numbers have been steadily growing, a flock of fifty birds were counted at Longham Lakes, Dorset, earlier in the week, and the first Spotted Flycatchers have also arrived.

Great Spotted Cuckoo by Cliff Woodhead

Southern overshoots have been well represented, mostly by the Hoopoe; there could have been between fifty and one hundred in the country.  It is difficult to know how many Black-winged Stilts turned up, eight were seen together in Kent, with several ones and twos later in the week that could have been some of these birds dispersing, or different birds altogether. A Great Spotted Cuckoo was found in Wales, and at least six Bee-eaters graced southern counties for a few days. Given the easterly airflow there were few birds from that direction, almost certainly because the winds actually originated out in the Atlantic north of Britain and came down through the North Sea and into the east coast and not from the continent.

Purple Heron by Northeast

The forecast for the next week is a little more unsettled than the last week, with westerly winds dominating all week. At times these will be quite light and during these periods birds will arrive. So, it will be more of the same although Ring Ouzel numbers will definitely be much lower. The last week of April is often marked by the mass arrival of Swifts and looking at the forecast there doesn’t seem to be much that will hold them up, so look out for them in the next few days. More of the BTO Cuckoos ought to make the last leg of their journey and, fingers crossed, Chris the Cuckoo (tagged in 2011) will arrive back. You can follow the Cuckoos here as they complete their journeys. As far as rarities go, I’m hoping for a Purple Heron, or Little Bittern on my local patch.

Thursday, 16 April 2015

What an amazing week

The weather conditions finally changed for the better, allowing migrants birds that were held-up further south to begin making their way north again, and they did! Ring Ouzel lead the way with over 500 birds being reported from the south coast to Northumberland.

Grasshopper Warbler by Amy Lewis

Willow Warblers piled in, over 300 arrived at Hengistbury Head, Dorset, on the 13th. Portland, also in Dorset, counted 500 on the same day. A few Sedge, Reed and Grasshopper Warblers arrived, along with a small number of Whitethroat and Lesser WhitethroatSwallows and House Martins are also back in good numbers and a few Swifts have also been seen.  Yellow Wagtails and Tree Pipits, Redstarts and Pied Flycatchers arrived bang on cue but although Blackcaps are now around in good numbers the main arrival is around a week later than the norm.

Pied Flycatcher by Edmund Fellowes

One of our latest summer migrants to arrive back is the Nightjar, sometimes the first birds are not seen until early May, so, one flushed from the car park at Dungeness, Kent on 12 April is very early. The first Nightingales have already taken up territories in some areas and are in full song and Cuckoos have been heard as far northern England. Four of the BTO satellite tagged Cuckoos are now back in Europe, one is in south west France and the other three birds are in southern Spain. Follow them as they make their way back to the UK here.

The warm southerly airflow that opened the floodgates also brought a number of Mediterranean overshoots with it, most notably Hoopoes, just under a hundred have been reported, mostly from southern counties, with at least eighteen present on the Isle of Scilly alone. At least three birds reached Scotland.  Wrynecks were also well represented, with at least thirty birds found. A couple of Woodchat Shrikes, Alpine Swifts and single Great Spotted Cuckoo, Scops Owl and Bluethroat, all added to the continental flavour but all of these were eclipsed by Britain’s second ever Great Blue Heron, found at the exact location of Britain’s first; Lower Moors, St Mary’s, Isles of Scilly, eight years earlier.

Bluethroat by Edmund Fellowes

So, what can we expect during the next week?

High pressure and relatively light easterly winds are forecast for most of next week which should allow more migrants to move and we should see the number of many of our common summer visitors grow. On the rarity/scarcity front we might see a slightly different mix bringing a bit of an eastern flavour with it. Red-footed Falcon, one or two more Bluethroats and a Pallid Harrier or two could be on the cards.

Thursday, 2 April 2015

Migration gets underway again

The strong north westerly winds brought migration to a halt prompting the migration stalwarts at Christchurch Harbour, Dorset to comment on their daily log for the 31 March, there were no incoming migrants today. However, as we go into the Easter weekend it looks like all that could be about to change; the wind has been dropping all the time over the last couple of days and migrants have responded accordingly. The first Sedge and Reed Warblers Warblers were seen, Swallows have begun to arrive in reasonable numbers and there have been a few more reports of House Martin and Sand Martin too.

Sedge Warbler by Dawn Balmer

Willow Warblers are also starting to appear and the first two Whitethroats of the spring have also been seen.  With the warmer weather starting to arrive, Osprey reports are also picking up across the UK. Today, 10 birds were seen, signalling that spring is definitely here. Most of these reports were noted as flyovers, from 14 different counties, ranging from Sussex, through Staffordshire and as far north as Co. Durham and Cumbria.

Osprey by

With the weather forecast to settle over the weekend, the floodgates could really open with Sunday possibly being the best day to go in search of summer visitors.

A Night Heron, on St Mary’s, Isles of Scilly might just be the forerunner for one or two more overshooting Mediterranean birds too. Following on from the Alpine Swift in Sussex earlier in the week my bet, albeit tentatively, is on Red-rumped Swallow. 

Red-rumped Swallow

Friday, 27 March 2015

Migration still slow

Chiffchaffs and Wheatears are arriving and beginning to filter north but the fairly strong northerly winds have effectively slowed migration down. Most of the other expected late March migrants have been thin on the ground too. There have only been a handful of Ring Ouzels, Swallows, Willow Warblers and Stone Curlews reported so far. 

Stone Curlew by P Doherty

Meadow Pipit migration has had its moments but is still slow, and overhead visible migration of ‘alba’ wagtails has been almost non-existent.One of the few early migrants to buck the trend is Garganey, with around forty birds reported and at least one making it as far north as Manchester. Ospreys have trickled in, a handful of which have already made it back to Scottish territories, and a small number of intrepid Willow Warblers have been seen and heard, along with one or two Yellow Wagtails and Tree Pipits.

Yellow Wagtail by Jill Pakenham

Things are definitely pushing up from the south though and there have been three overshooting southern European birds this week, two Black Kites in Kent and a Hoopoe in Ireland but it is going to take a serious change in the weather before the floodgates really open.

The weather forecast for the next week, strong westerlies and some serious rainfall at times, isn’t looking too promising either, at least until the middle of next week but should we get the odd quiet spell we could well see the floodgates open a little, and if they do, expect Willow Warblers, Blackcaps Ring Ouzels and Stone Curlews to start appearing on territory.
The weather might not be so hard on those birds heading out across the North Sea and we could see movements of Brent Geese, Wigeon, Whooper Swans, Redwings and Fieldfares, amongst others this week.

Male Redhead by Jill Pakenham

On the rarity front, my bet is still with a rare duck, or two. A Redhead would help to redress the balance of records lost to the recent British Birds Rarity Committee review – only one record now stands, a male seen in Nottinghamshire on 8-27 March 1996.

Friday, 20 March 2015

Still early but birds are on the move

During the last week there have been windows in the weather that have allowed birds to push north – Chiffchaffs, presumably held up further south arrived, not exactly in force but in numbers that made for some good counts at a few sites. Over 200 were recorded at Portland, Dorset on 18 March. Meadow Pipit migration is also a feature in March and it was beginning to look like it might not happen this year, however, taking advantage of the same weather window as the Chiffchaffs.

Chiffchaff by Amy Lewis

Meadow Pipits did finally begin to move in good numbers, over south coast watchpoints at least.
More Wheatears, more Sand Martins and a few more Swallows were also on the move, only a handful of the latter were involved though. The first Ring Ouzels were reported and a small number of Willow Warblers were also seen and heard.

So, what can we expect for the nest week?

The weather is forecast to be pretty similar to this week with the wind moving from the north through the whole of the compass and back to northerlies by the end of the week. At times there will be light winds which ought to provide more windows in the weather and, at these times birds will begin to move. It is still early in the season but we should see things stepping-up a gear. It ought to be a week of Chiffchaffs and Meadow Pipits but we can also expect a few more Willow Warblers and Sandwich Terns to crop up too.

Sandwich Tern by Andy Mason

Cliff-nesting seabirds ought to begin to increase as more and more return to their colonies, particularly during quiet periods in the weather, and seawatchers could be treated to some spectacular wildfowl movements – now is a good time for scoters to be on the move. It is worth checking out inland waters too, as a few Common Scoters do seem to migrate over land during March. Other wildfowl on the move will include Wigeon, Pintail, Teal and Shoveler, and flocks of geese should also be a feature, as Brent, Pink-footed, White-fronted and Greylag geese all start to make their way north.

Redwings and Fieldfares could also head out mid-week as the winds become more favourable for a North Sea crossing. The weather isn’t looking so good for those Redwings that are heading back to Iceland though. and along with Whooper Swans, Northern Britain could see good numbers of both gathering in readiness for more suitable conditions.

Scarcity of the week has to go to the immature White-tailed Eagle that did a tour of East Anglia during the early part of the week and is still present at the time of writing. At this stage it is impossible to know where this bird originated from. However, during the last few days it has visited several points along the Norfolk and Suffolk coast, perhaps looking for the ideal conditions to cross the North Sea, giving us a clue of its possible natal area. The bird is ringed but the ring number hasn’t been visible so far.

Bufflehead by Luke Delve

With the winds coming from all direction this week it is hard to hazard a guess at a rarity but it could well be a duck that has spent the winter further south. Of the sixteen Buffleheads that have been accepted in Britain, five occurred in March.

Thursday, 12 March 2015

They're here!

The first decent arrival of summer migrants arrived last weekend, on the wave of warm southerly airflow that the southern half of the country enjoyed. Over one hundred Sand Martins were reported, with a few birds making it as far north as Cheshire. Around half as many Wheatears with most being seen, rather unsurprisingly, in southern counties, a few did make it into Wales and at least one bird was seen in Northern Ireland. 

Sand Martin by Andy Mason

Other summer migrants arriving at the weekend included at least one Swallow, a couple of House Martins and Little Ringed Plovers, around a dozen Garganey and up to four Ospreys. The predicted Hoopoe didn’t show but there was a flavour of the Mediterranean with at least one, and possibly as many as three Alpine Swifts being reported, only one of these showed well, a bird that graced the skies over Wolverhampton on the 9th March.

Alpine Swift by Su Delve

Visible migration watchers also enjoyed some movement – A steady trickle of Meadow Pipits heading north was a feature of south coast watchpoints during the early part of the week, whilst northbound Pink-footed Geese dominated proceedings at east coast sites. West coast watchers were treated to some impressive auk movement, mostly Razorbills heading north. Check out the BTO ID video here.

Meadow Pipit by Nigel Clark

With stiff north easterly winds forecast for this weekend it will be quite different from last weekend – whilst a few southern migrants will still arrive most will struggle, however, that could all change during the early part of next week when the winds turn more southerly again. The east coast will be the place to be this weekend. More geese, divers and gulls should be on the move with the easterly wind pushing them close inshore, and wildfowl, Teal and Pintail could move in good numbers, it could also be the east coast’s turn to enjoy some auk passage. 

Once the winds turn southerly again we could see the first big arrival of Chiffchaff and more hirundines. On the rarity front and given the easterly winds and the fact that there have been a few March records before, Rustic Bunting could be on the cards, although later in the week something from the south is more likely.