Obviously too good an opportunity to miss I wondered how best to go about seeing them. I was staying at the Meridien Hotel on Luanda Bay, and the solution was to climb the hotel fire-escape to the 28th floor where an unlocked gate gave access to the large flat roof - and some spectacular, uninterrupted views over downtown Luanda and the Bay.

The following photographs were taken from the roof of the Meridien Hotel, Luanda in the late afternoon as a group of about ten "African Black Swifts" and twenty Little Swifts appeared out of nowhere and began hawking over the centre of the city some distance from me. Many of the photos are highly-cropped and enhanced (hence the "noise" evident in the backgrounds) and unfortunately almost all of them were taken either almost into the sun or with the sun to one side of me which has burnt-out some of the finer details. Most of the photographs were taken from almost directly underneath the swifts as they passed over, and the strange orientation of Figures 6 and 7 is correct (see below for explanation).

Whilst I have little experience of African Black Swift in other parts of its range, I hope the text that follows will be of interest.

  - The "Luandan Black Swifts" had a distinctive flight action which consisted of a fairly steady level flight broken with short glides.
  - They appeared to be in pairs - or at least were interacting in a way that suggested that they were paired-up or courting.
  - A peculiar action was noted (and photographed) on a number of occasions where one swift would chase after another then rise up sharply and almost stop in mid-air, before performing a "tumble" that was reminiscent of the flight of a "tumbling pigeon" - the strange orientation of Figures 7 and 8 (below) is therefore correct and shows the moment either just before or as the swifts stall before the tumble.
  - I heard a vocalisation just once: as one swift raced up to another it gave a double, rasping call with a rising and emphatic end note that I transcribed as "zzzzzzzZZZTT", very unlike the typical screams of Common or Pallid Swifts, but similar to the description of the call given in "Birds of Western Africa: An Identification Guide" by Borrow and Derney for African Black Swift.

A further twist in this tale has been the suggestion by several experienced African birders that, given the limitations placed on the ID because of the less than perfect quality of the photographs (my words, not their's), the birds might be Bradfield's Swifts Apus bradfieldi - a SW African endemic thought to occur much further south than Luanda.

I'm now very grateful indeed to Gerald Driessens, illustrator of the acclaimed "Swifts: A Guide to the Swifts and Treeswifts of the World", for commenting on these swifts. Gerald mailed me twice, and the following is a compilation of his expert comments:

 

Yesterday, I had a look through my Swift-files and compared your photographs to them. I feel very convinced now that [these are] not Bradfield's. Bradfield's is much more robust in build, showing a bigger, flatter head (as in Pallid) a fuller body and -especially - a much more thickset tail, which is regularly held in a solid thick spike - the tail fork [on your birds] looks too deep and quite sharp. Bradfield's looks - as in Pallid - pale brown and 'moth-eaten', with the dark tail being the most obvious dark part of the plumage. Some pictures at least would have shown a much browner bird. I feel comfortable that it is an African Swift - the scaling on the underparts is visible in that species. I can't find any suggestions for another species. The rather dark throat patch could, indeed, suggest Fernando Po [which in "Swifts" is considered a subspecies of African]. However, taking into account variation in other Apus-swifts, and the fact that in most species the throat patch becomes darker and more diffuse through wear, it would be rather subjective to conclude upon a subspecies, as several of them are darker than the other. This is always the problem with subspecies, and especially in swifts. Rarely, the division of subspecies is so clear that there's only little intergrading between them. In swifts, we mostly have to rely on photographs and it is very difficult to assess the original colour of the live bird. This will be the everlasting reason why some species, like eg. Schouteden's Swift [Schoutedenapus schoutedeni, a species known from only 5 specimens from E Dem Rep of Congo], is unlikely ever to be rediscovered.

 

 

 

 

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7: This and Figure 8 are correctly orientated, and appear to capture the moment when the swifts began the "tumbling" flight action mentioned in the text above.

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

 

For more on Swifts on this site go to:
Little Swifts - Luanda, Angola, May 2005

Little Swifts - Nairobi, Kenya June 2005

Pallid Swifts - Dubai, UAE Jan 2005

 

 

All photographs © Charlie Moores