Proposal (734) to South American Classification Committee

Add Apus apus (Common Swift) to the main list

This species has been photographed offshore Suriname and identified by Marijke de Boer et al. (2014). No previous photo or specimen evidence exists for this species in South American.

The photos (see below) show all diagnostic features:

The following text has been copied from de Boer et al. (2014):

“The characteristics of the swift in the photograph included (1) a relatively large, slim, dark body, with a long deeply forked tail; (2) upper and underwing-coverts apparently darker than the primaries and secondaries; (3) very long, sharply pointed, scythe-like wings; and (4) a faint white chin patch (Fig. 2A). Additional photographs taken by JTS (Fig. 2B–D) clearly revealed the well-defined white chin (upper throat) and scaly appearance to the lower belly and undertail-coverts due to these feather tracts having pale fringes. Pale forehead feathering extended above the eye to form a weak supercilium. Based on structural characteristics and plumage details, the bird was confirmed to be a Common Swift. The presence of white fringes on the forehead indicates that it was possibly a juvenile, although the pale trailing edge to the underwing- and upperwing-coverts of juvenile Common Swifts are not clearly visible. The clearly forked tail does not match the shorter, broader and square-tipped tail of White-chinned Swift. Other than White-chinned Swift, there are no dark long-tailed swifts with a white throat patch in the Americas. For example, White-tipped Swift Aeronautes montivagus of South America has sharply pointed wings, a rather long tail with a slight fork, dark plumage contrasting with a white throat and, unlike Common Swift, distinct white thighs. Other similar-looking Apus species can also be ruled out. Plain Swift A. unicolor, which occurs in Morocco, Madeira and the Canaries, has a mottled dark grey throat patch, is smaller with narrower wings, and has a more deeply forked tail. Pallid Swift A. pallidus, which mainly occurs around the Mediterranean, the Arabian Peninsula and North Africa, is slightly smaller than Common Swift, overall much browner, has less pointed wingtips, a less deeply forked tail, smaller and paler head (with a grey-white forehead), distinct dark mask and a larger white throat patch15. Alexander’s Swift A. alexandri, which occurs in the Cape Verdes, is a small bird with relatively short wings, a shallowly forked tail, and indistinct pale throat patch. Bradfield’s Swift A. bradfieldi from Namibia and South Africa is much paler than Common Swift. Finally, African Black Swift A. barbatus of East and South Africa is probably the most similar in appearance to Common Swift; however, it is much darker overall, has less pointed wingtips and darker primaries.”

Reference:

Marijke N. de Boer, James T. Saulino and Andy C. Williams. 2014. First documented record of Common Swift Apus apus for Surinam and South America. Cotinga 36: 107–109

Otte Ottema, December 2016

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Comments from Mark Pearman: “The original article has colour photographs which helps. The sooty brown body and underwing-coverts are darker than any white throated congener, and the extent and form of the white throat patch in combination with the proportionately long forked tail certainly do confirm identification as Apus apus.”

Comments from Remsen: “YES. Published photos with identification corroborated by experts.”

Comments from Stiles: “YES. The photographs and expert opinions are convincing.”

Comments from Areta: “YES. As explained by Mark, the bird shows diagnostic features of Apus apus.”

Comments from Robbins: " YES, to accepting Apus apus to the list based on the photographs in de Boer et al. (2104)."

Comments from Pacheco: “YES. The published images attest to the accuracy of the proposal.”

Comments from Jaramillo: “YES. I do think that the analysis vs Pallid Swift is weak, Common and Pallid Swift are quite similar in my experience. Yet, as Mark notes the color photos help and you can see a lack of obvious pale forehead, so Common Swift it is.”