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 28 February 2014

Spring might be back on hold

The short spell of warm southerly airflow that we experienced last week did bring a small number of summer migrants to the UK. A handful of Sand Martins were seen at a couple of south coast locations, a Swallow was seen in Somerset, a pair of Garganey were seen in Buckinghamshire and a Great Spotted Cuckoo got as far north as Ouessant, Brittany There was also some evidence of a small arrival of Chiffchaff on the south coast.

Garganey by Dawn Balmer

The return to, at times, strong westerlies put paid to further arrivals from the south this week but it didn’t stop some of our departing migrants from moving. Small numbers of Pink-footed Geese have been seen moving north along the east coast, and Greylag Geese have also been seen on passage over Fair Isle.

There has also been some auk passage past west coast watchpoints, mostly involving Guillemots and to a lesser extent, Razorbills. There have also been a few Puffins on the move but it seems that a large number of Puffins were caught up in the severe storms that lashed the Bay of Biscay last week. A coordinated count of dead Puffins on the beaches of France, between Finistère to the Spanish border, found over 12,000 individuals, amongst over 21,000 seabirds. Most of these birds would be just about to start the return journey to their breeding colonies, Ringed birds recovered so far have come from colonies in west Wales, northern Scotland, Orkney and Shetland.

From much further south, we received a report of Pomarine and Arctic Skuas on the move, along with a small number of Grey Phalaropes, in fact these birds were observed on passage from a research vessel 20 nautical miles off the coast of Ghana. With a bit of luck these birds could be flying past a British headland in a month or so. See here for more.

Pomarine Skua by Joe Pender

One of our satellite tagged Cuckoos has begun the second leg of his return journey to the UK and is now in Ghana, just north of Lake Volta. It won’t be too long before some of the others join him there.

The weather forecast for this weekend doesn’t look too promising for much migration to take place, however, there will be a small window during Saturday afternoon and Sunday morning when the winds in southern Britain will be light and from the south, courtesy of high pressure over France. If there are any migrants holding-up in France, Sunday morning might see them arrive here. It is still very early though so it would only involve a small number of birds. Wheatear has to be favourite with perhaps the first flush of Chiffchaffs.

Thursday 20 February 2014

One Wheatear doesn’t make a summer

One Wheatear doesn't make a summer...however, it is the first sign that the arrival of long-distance summer visitors is upon us. 

On 18 February, we received a report of a Wheatear in Derbyshire and, although it is early it is not unprecedented. Wheatears spend the winter months south of the Sahara, from Mauritania and Sierra Leone to the Indian Ocean. Apart from a few birds in Iraq, and the odd straggler in the United States, the entire world population winters in Africa. Of course we don’t know where Tuesday’s Wheatear spent the winter months, and maybe it didn’t cross the Sahara, but it could have. Wheatears begin to leave their winter quarters in early January, and by mid February passage is well underway in North Africa. So, if the Derbyshire bird began its migration in Early January it could complete the 4,500km (3,000 miles) journey in the six week period.

Wheatear by Amy Lewis

From Saturday in to Sunday, high pressure is forecast to build over southern Europe, in fact high pressure and very light winds are forecast to stretch all the way from North Africa to Central France, so, there is a small chance that one or two more Wheatears might make it back to the UK over the weekend, although  the south-westerly winds in the English Channel might just prevent any Wheatear that has made it that far north from making the crossing.

Met Office pressure chart for Sunday 23 February 2014

Friday 14 February 2014

Feels like summer

As I write this on Valentine’s Day there are several reports of summer visitors on the bird information websites. These include up to six Lesser Whitethroats, four Common Whitethroats and five Swallows, with records from the south coast to Northumberland. The winter period has also seen reports of Turtle Dove, Wheatear and both Willow and Garden Warbler, not to mention scores of Blackcaps and Chiffchaffs. In fact, so far in February there have been twelve species of warbler recorded. Ok, so three of them are from the east, Yellow-Browed, Pallas’s and Hume’s, and one, Yellow-rumped, is from North America, and all probably arrived here back in late October. There are two that are resident warblers; Cetti's and Dartford. But what is interesting here is that they have, so far, all survived a British winter. Also interesting is that the last time Swallows successfully over-wintered in the UK was in 2009, during another relatively mild winter.

Turtle Dove by Sue Hunter

So, with all these ‘summer’ visitors at large in the UK it is easy to think that at least some of them might be early migrants, particularly a few of the Blackcaps and Chiffchaffs but this doesn’t seem to be the case. Most of the records are away from migration watchpoints and many of them can be traced through the winter months, having spent that time in BTO Garden BirdWatch participant’s gardens, or regularly featuring on BirdTrack lists.

Sand Martin by Andy Mason

However, it won’t be long before we do start seeing a few early migrants. Certainly by the end of February there is a very good chance of Wheatear and Sand Martin turning up, and if we do experience a few days of warm southerly airflow they could be joined by a few Swallows, and maybe even the odd House Martin. There have also been several February records of Great Spotted Cuckoo, with the earliest being found on the 14th, so if we do get the warm southerlies, who knows?


On another note, we have just heard about a Little Egret in Iceland that was ringed as a chick in Galway, this adds to other birds ringed in the UK that have been found as far away as the Azores and the Canaries, for more on these birds, please visit http://btoringing.blogspot.co.uk/ . 

Our Cuckoos are also on the move. As of 13 February three of them had completed the first leg of their mammoth journey back to the UK. For more information, and to follow them as they make their way back, please visit, http://www.bto.org/science/migration/tracking-studies/cuckoo-tracking

Thursday 6 February 2014

Spring migration getting underway – or not

There are signs that birds are on the move. During the last week, Bramblings have moved into my garden, and I know from previous years that I may well see them on a daily basis from now until early April. I also know that I get a large turnover of birds during that time – some days there are more females than males, and on other days young birds in their 1st winter dominate. Over the course of the next couple of months over a hundred different individuals could move through the garden, almost certainly on their way to the east coast and, at some stage crossing the North Sea. So, for me, this is one of the first signs I get that spring migration is underway.

Brambling by Jill Pakenham 

In a couple of weeks time, Siskins will be doing the same; moving through the garden. I only ever see a maximum of a dozen or so birds but a couple of years ago, over a three week period in March, almost two-hundred Siskins were trapped and ringed in my garden, proving that there was a large turnover of birds.


Siskin by www.grayimages.co.uk

But what about the Sora on St Mary’s, Isles of Scilly? It was seen for the first time this year on Saturday 1 February. I say this year because it may well be the bird that was at the same site in mid-October last year. Or, could this be a bird on the move? There is a chance that it could be a new arrival – it was seen just ahead of a deep low pressure system that tracked across the Atlantic at great speed and, although it seems a little early for a Sora to be on the move, the first ones start to appear in southern USA in early March, it wouldn’t be outrageous to think that it could be an early migrant; would it?

I have seen Wheatear, Swallow and House Martin in mid-February on the Isles of Scilly, and those birds must have been on the move in early February and prone to getting caught-up in bad weather. The fact that at the time there was a warm southerly airflow that also brought my earliest ever Hoopoe to the islands obviously helped them on their way, but what if it had been a fast tracking low out of the Mediterranean that crossed the Atlantic to North America in a couple of days, unlikely I know, but in those conditions those birds could have arrived in a very different place indeed.


So, has spring migration already begun? Almost certainly. Is the Scilly Sora a freshly arrived trans-Atlantic vagrant? Who knows? It’s not impossible.