Plain Swift mainland Portugal (1 Viewer)

[John Cantelo]

A tweet by Magnus Robb (see below) reveals that Plain Swift (30!) have been reported from Porto by Paulo Belo, This is an extraordinary range extension and must open the possibility that they may be found elsewhere in Portugal and quite possibly Iberia and beyond. The account describes the call as "quite distinctive" which runs counter to what relevant guide suggest.

 

[John Cantelo]

I'm surprised that this remarkable news hasn't caused more interest. There's a sound recording made by the finder on xeno-canto (see https://www.xeno-canto.org/615885) dated 17/01/2021 which, as the photo above is dated 15/05/2021, suggests the birds are resident as per (most of) the Macaronesian population. This should certainly help identification as both Common & Pallid Swift should normally be absent then. Intriguingly, however, de Juana & Garcia (Birds of the Iberian Peninsula) dismisses claims of Common Swift "recorded very early or very late in the year and even in mid-winter" from Spain & Portugal as misidentified Pallid Swift (which certainly appear earlier & hang around later than Common). It cannot be discounted, surely, that some of these could have been Plain Swifts.

On a decent view, Pallids shouldn't be confused with Plain Swift. However, any unseasonally late/early/wintering all-dark swift is likely to be put down as Pallid on an indifferent or poor view. Is it possible that even some winter records of Pallid, particularly of small groups [6 at Loures, Lisboa (Dec 2015), 4 at Laguna de Mejorada (Dec 2015), up to 15 at Alange Reservoir/village Badajoz (Dec 2010, Dec 2011 & Feb 2012)] could involve Plain Swift? There are reports too of a small population of Pallid Swift wintering in Seville - could Plain Swift be hiding amongst them?

As for the calls, I think here as in many discussions of bird ID "quite/very distinct" has almost become synonymous with "distinguishable with experience". When my hearing wasn't so duff I could pick out Pallid on call when Common Swift were around for direct comparison but lone birds/groups are more tricky. I felt Plain Swift sounded a little different (shriller?) but even listening to recordings (now with my ear next to the speaker) I'd call the differences subtle and probably very tricky in field conditions for most observers.

 

[jurek]

It could be a vagrant flock, because few years ago it was discovered that Plain Swift is a long distance migrant to mainland Africa which winters in Congo rainforest. They also were seen for several years in coastal Morocco, but in this case it could be simply migrants staying en route.

On Madeira I found Plain Swift to be rather different than Pallid / Common, being a clearly smaller bird with a weaker, martin-like flight, hunting low and slow. But this could be, indeed, not obvious, especially if a whole flock of swifts behaves the same way.

 

[John Cantelo]

It could be a vagrant flock, because few years ago it was discovered that Plain Swift is a long distance migrant to mainland Africa which winters in Congo rainforest. They also were seen for several years in coastal Morocco, but in this case it could be simply migrants staying en route.

On Madeira I found Plain Swift to be rather different than Pallid / Common, being a clearly smaller bird with a weaker, martin-like flight, hunting low and slow. But this could be, indeed, not obvious, especially if a whole flock of swifts behaves the same way.

Yes, I too have read that Plain Swift has been found wintering in the Congo (and elsewhere on mainland Africa). That the birds have remained in the same area of mainland Portugal from January into May (as it would seem to be the case from the dates of the sound recording & photo) suggests it may be more than a vagrant flock given that the species breeds March-August. As the comment notes, this is a 'developing story' full details of which will appear in Dutch Birding (and hopefully elsewhere). I've seen Plain Swift on Madeira too when I felt they had a more fluttery flight and seemed less hefty than Common Swift but I could never quite convince myself that my assessment of their 'jizz' couldn't be the result of autosuggestion thanks to reading texts that told me so!

 

[KenM]

Have had Plain Swift on Fuerteventura over the Xmas period although not on every visit, the same with Pallid over the same period albeit less so.

Cheers