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, 19 May 2017

Hirundines in a hurry!

Ordinarily mid-May sees spring migration begin to slow but with northerly winds dominating the early part of the spring, several species seem to have been held-up, and the last few days have seen hirundines on the move, mostly House Martins but also smaller numbers of Swallows and Sand Martins too. Early indications from the BTO House Martin survey suggest that it is a slow start to their breeding season; perhaps there are still birds that haven’t arrived back yet.

There will still be plenty of birds on the move and, for some, now is the time to catch up with them. Arctic Terns will peak in the next week or so, mainly moving up the west coast but also through the Severn and Trent valleys, as some of them make their way into the North Sea. This is also a good time to look out for Long-tailed Skuas, with the very best site being Aird an Runair, the most westerly point of the island of Uist in the Western Isles.

Arctic Terns by Jamie MacArthur

Nightjars typically arrive back on their breeding territories around mid-May and migrants birds can be found almost anywhere, and if you stand any chance of seeing Golden Oriole in Britain, now is the time.

May is the month that Honey Buzzard arrive back and in the right weather conditions, move through the country. South-easterlies are what is needed, and if we do get winds from this direction in the next couple of weeks it could get exciting, with Red-spotted Bluethroats, Wrynecks, Red-backed Shrikes and Icterine Warblers turning up.

Red-spotted Bluethroat by Edmund Fellowes

The weather over the weekend is due to turn southerly for a short time with a hint of south-easterly early next week, whether or not this will be strong enough, or come from far enough east to turn up eastern bound migrants will have to be seen but it will be a change from the westerlies of the last week or so and a change in wind direction quite often turns birds up and allows others to move.

At this time of the year anything can turn up, as evidenced by the Great Reed Warbler that was found in a tiny reedbed on the BTO’s Nunnery Lakes reserve in Norfolk, the first for the site. It would be fantastic if it was followed up with a Crag Martin next week.

Great Reed Warbler by Mike Symes

Friday, 5 May 2017

Wind stuck in the north

With the wind stuck in the north migration has slowed a little but not come to a halt. Fortunately there has been varying degrees of east in the wind and this has resulted in what could be described as a Black Tern week, with birds being reported from many wetland and seawatching sites across the country.

Black Tern by Lawrence G Baxter
What is really obvious is the lack of Swifts. A small number have arrived but the usual mass arrival during the first few days of May hasn’t happened. The stiff northerlies are definitely blocking a mass arrival at the moment but as soon as conditions allow we should be in for an impressive movement of these amazing birds, this may well happen midweek when, if the forecasters are correct, we will experience a short period of light southerly winds.

This will also allow some of our later spring migrants to arrive too, and it is well worth looking out for Spotted Flycatchers. For those lucky enough to have easy access to the coast skuas, in particular Pomarine Skuas, will be on the move, along with more Black Terns, Little Gulls and Arctic Terns. South-easterlies are the ideal conditions for these and we might just be lucky midweek.

Pomarine Skua by Jo Pender
Now is the time to catch-up with a few waders as they make their way north, in particular Whimbrel, Dotterel and Wood Sandpiper.

Dotterel by Edmund Fellowes
We are just coming into the period when some of our scarcer migrants move and the right now is a great time to look out for Golden Orioles, Red-backed Shrikes and Wrynecks.