Pallid Swift Identification:

What does it take?

Martin G. and Mike Langman

The identification of Pallid Swift has received much scrutiny in the last 2-3 weeks caused by an unusual influx of juveniles into northern and western Europe. As well as several in the UK,  4-5 were in the Netherlands in late October per Nils van Duivendijk (only one previous accepted record) and from Spain, Dani López-Velasco writes:  “A big influx (largest ever) of Pallid Swifts is taking place along the northern coast of Spain, where they are usually rare to very rare (i.e. 16 together at a headland in Asturias, N Spain, in a region with only a couple of previous records)…”

A few days after watching a much discussed Pallid Swift at Hartlepool headland I found this Pallid Swift at Flamborough. Inevitably I (once again) went through the big question: What does it take to identify one?

I think both the field views and photography can help (or hinder) a correct identification. The right kind of both are needed!

Here’s a quick and dirty list of the kind of criteria to have in mind when it comes to Pallid Swift ID in the autumn. It’s based on a breakthrough list of characters itemised by Nils van Duivendijk after he found the first Dutch record in 2006, includes some material based on my research and the more recent superb article (in Swedish) by Hans Larsson.

  • structure: plump bodied, broad winged, rounder wing tips (not related to relative length of p9 and p10) and less forked tail: specifically t5 about same length as t6, though some juv. C. Swift similar) (10 tail feathers). Broader, ‘shark-like head with bill more prominent
  • paler/ browner overall plumage, with paler framed patch on mid wing from below. Tail feathers with obvious pale inner webs
  • extensively pale head with diffuse edge into darker body plumage. Isolated dark eye.
  • breast and belly feathers with pale bases, subterminal dark line and pale tip. Scaly effect obvious over whole underparts
  • fringes of upperwing coverts off white evenly spread over all wing coverts
  • pale/whitish tips to mantle and scapular feathers (also found on pekinensis C. Swift)
  • median and greater underwing coverts paler than lesser underwing coverts

James Lowen (lots more of his images here) kindly provided a few off his lovely shots of a bird at Foreness in Kent. These illustrate some of the points above. James also has a new book out 🙂




Pallid s JCL_2631


Here come some timely comments from Mike Langman on the issue of field views and photos.

Mike Langman’s comments:

I’ve been very interested in the thread on the Cleveland Pallid Swift on Birdforum  the identification swung from Pallid to Common then back to Pallid again with some very informative postings. I will admit when I saw the initial photographs I considered it to be a Common Swift, the general (quite black looking) colour of the bird and the apparent grading of what appeared to be a smaller white throat patch just didn’t match up to Pallid for me. This all appears to be down to lighting, the first published photos in the thread were taken in bright low sunlight. But the photos taken in dull light shown later in the thread are much more Pallid Swift looking!

There is some comment on whether field observation is taking a back seat to photos in the thread too. This bird was identified as Pallid by the finder and some of those seeing the bird in life were arguing the case for Pallid early on in the discussion. Pallid Swift can be a very difficult bird to identify we all know of the pitfalls of juvenile Common Swift and even possible occurrence of pekinensis Common Swift – but on some occasions Pallid can be actually quite easy to identify.

I’m sure I’m not the only person to have been caught out when abroad misidentifying Pallid Swifts seen at dusk or up in the sky as Common Swifts, despite looking hard at the physical appearance of these silhouetted birds to make an id. Then seeing the same birds in dull light or against a darker background corrected the original identification to Pallid. Field experience is still vital in birding, our eye can see tone and colour better than the best dynamically ranged DSLR. We might not pick up on feather detail on a fast moving bird like a swift – but we can interpret a lot more of what we are seeing sometimes better than a camera can.

Martin your photo’s do suggest some good features for Pallid but, surely, it will be the field experience and descriptions of what you saw that will give this bird the best chance of being accepted as Pallid. As – long as you did spend time looking and not getting the camera ready, concentrating on getting the shot. There were some disparaging remarks on the forum about previous records – ‘seeing a bird briefly making some notes and hoping it flies off quick’. Is birding and birders really giving up completely on field notes and observation? If so, I think this would be to the detriment of all birding. Making notes is how I was brought up, and as an artist are what fills my pages of my yearly notebooks it relies on the observer looking hard at a bird taking in as much as possible in the heat of the moment. I only note what I see and through practice over many years hope I usually get the details right. I still carry a camera (albeit a light weight superzoom bridge camera) – they are becoming an essential tool of the modern-day birder.

Your record reminded me very much of a Pallid Swift I saw at Hope’s Nose Devon in November 2010 . The difference was I actually saw the bird in dull light and against a dark background and given the opportunity to see it again twice after the bird was blown back into the bay after trying to make an exit. The weather was so appalling I didn’t take my camera with me on the day it would probably have been damaged in the rain – a mistake – perhaps destining this bird to the ‘not proven’ category, although the jury is still out on it! I have looked hard at thousands of Swifts in all sorts of light and in many European countries and not once seen a Common Swift exhibiting the colour tones and features this bird showed. While leading a tour to Uludag, Turkey during mid-September 2013 some birds on (more likely to be Pallid given time of year and site) caused me Id problems initially being high in the sky, but as the light changed they exhibited the extensive white throat and face and black eye sockets, umber brown contrasting uppewings with blackish primaries, darker brown saddle and slightly paler dull brown rump leaving me with no-doubt they were Pallid Swifts.

There is still the nagging question – how many, unquestionably, proven records are there of late October and November Common Swifts in the UK?

Mike Langman, Devon

MG: Not deliberately juxtaposed- here is some feedback on the photos of the Flamborough bird.  I do agree with Mike, without my first views of the Flamborough bird-  which I was enabled me to identify it to my own satisfaction at least, I certainly wasn’t going to rely on distant and going away images. Interesting to get the feedback (having reviewed them myslef) nevertheless:

Feedback on the Flambrough bird of 26th Oct

Hi Martin,
All what can be seen looks good for Pallid I think: indeed thick and paler head and relative shallow tail-fork with t5 not (obvious) longer than t4. Furthermore relative broad hand and rather transculent flight-feathers and tail-feathers. Unfortunately there are no real plumage details visible, but the above things look too good to ignore.
Cheers, Nils [van Duivendijk]


Hi Martin!
Thanks for the email and pics! It seems a quite perfect Pallid from what can be told I think! Structure, as you say is very good, with especially a rather flat forehead and quite prominent bill, giving it the more triangular and shark-like head shape. It looks difficult to evaluate the underwing coverts with certainty, unfortunately. The “alien eye” is very striking and even if the light is playing tricks a bit here, I don´t think a Common Swift would look this much of an Alien.. So, all in all I´m personally convinced it must be a Pallid, but it may be harder to prove it “in court”, at least in a regular autumn. This year seems to become historic (already is..).
BTW, I went to our only prominent cliffs in my part of the province of Scania yesterday in hope for a Pallid. To my surprise I did found a Swift, but it turned out to be a White-rumped! Still in shock today…
Best wishes,
Hans [Larsson]



2 thoughts on “Pallid Swift Identification:

  1. Jochen Dierschke

    I think one – in my opinion – good feature is not only the shape, but the flight action. Pallid has an obvious flight style with wing-beats not as deep as Common Swift but more like a Common Sandpiper and inbetween long glides with wings hold downwards. Although this might not be a 100% field character (and it certainly need some experience!), this is a very good pointer towards Pallid. I’ve never seen this behaviour and flight action in Common SXwift. In October 2009 there was a Pallid Swift claimed on Helgoland and when I saw the bird, I immediately agreed, just because of the flight style. The weather was rather dull, the bird appeared completely dark and although I was convinced that it must have been a Pallid, all other arguments were against the ID or at least not conclusive. I was angry that the flight style then was not conclusive, but 1 hr. later, the sun was shining and there was no doubt anymore that it was a Pallid Swift.

    See a picrture here:

    The flight behaviour in combination with the structure gives a Pallid Swift (at least juveniles in late October) in my opinion a unique appearance. Although this is – without video footage – difficult to assess for a Rarities Committee, this is in my opinion a good feature!

  2. Laurent Vallotton

    You might be interested by this forthcoming article about a very probable case of hybridisation between A. apus and A. pallidus in Switzerland (article in French, see reference below). The hybrid pair raised 2 youngs, one with A. apus phenotype, one with A. pallidus phenotype!

    Oberli, J., A. Gerber & A. Bassin (2013) : Un Martinet pâle Apus pallidus dans une colonie jurassienne de Martinets noirs A. apus : un premier cas d’hybridation? Nos Oiseaux 60 : 205-208.


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