Tuesday 17 June 2014

Barn Swallow x Cliff Swallow

Barn Swallow x Cliff Swallow hybrid, near Kersey, Weld County (Colorado, USA), 15th July 2012 - copyright Steve Mlodinow
(photo ID: 1265)


Steve tells us that this bird was among a flock of about 1000 birds, mostly Cliff Swallows, but also a fair number of Barn Swallows.  They were near a bridge under which both species breed.  The hybrid heritage here is pretty obvious.  When the bird spread its tail more widely, even more white spots could be seen.

Steve had seen two Barn Swallow x Cliff Swallow hybrids previously but neither had the odd (and slightly asymmetric) white throat shown by this individual.



Barn Swallow x Cliff Swallow hybrid (same bird as in photo ID 1265 above), near Kersey, Weld County (Colorado, USA), 15th July 2012 - copyright Steve Mlodinow
(photo ID: 1262-1264)


Barn Swallow is pretty clear in the next bird too, though whether the other parent was Cliff Swallow or Cave Swallow is less obvious.  Steve thinks the dark blue on the throat indicates Cliff Swallow.

Barn Swallow x Cliff Swallow hybrid, north of Cameron Prairie NWR, Cameron Parish (Louisiana, USA), 25th April 2015 - copyright Steve Mlodinow
(photo ID: 2237)


Steve didn't find the next one quite so easy at first:
"I initially glanced at this bird and thought 'Cliff Swallow' given the nicely demarcated dark orange throat.  Of course, it was at some distance, on a wire, lined up with a bunch of Barn Swallows and one Tree Swallow.  It took me quite some time to realize how dark the forehead was, that there was only light streaking on the undertail coverts, and that there was some buff down the flanks.  That sent me off in the Cave Swallow direction.  But the throat was wrong for Cave Swallow.  And I stood stuck.  Michael O'Brien and Peter Pyle kindly unstuck me with the Duh (nicely put) revelation that it was a Barn x Cliff/Cave Swallow.  That would explain the rather extensive buff beneath, the tail nearly reaching the wingtips (whilst perched, of course), and the minimal dark throat markings.  The dark throat, with a hint of dark markings at lower edge, strongly suggests Cliff x Barn Swallow."



Barn Swallow x Cliff Swallow hybrid (same bird as in photo ID 1265 above), near the Logan County entrance to Prewitt Reservoir (Colorado, USA), 15th September 2012 - copyright Steve Mlodinow
(photo ID: 1251-1254)



The next bird is another tricky one.  Dave thinks it may be a hybrid on account of (1) the white forehead recalling Cliff Swallow, (2) the under primaries and secondaries appearing white like Cliff Swallow not dark like Barn Swallow (and not merely made too translucent by sunlight) and (3) the wide breast band possibly showing Cliff Swallow heritage (unlike European Barn Swallows, American birds have only a very narrow and incomplete breast band).

possible Barn Swallow x Cliff Swallow hybrid, Grand Isle, Lake Champlain (Vermont, USA), 11th-12th August 2013 - copyright Dave Hoag
(photo ID: 1802)


Personally I find the underwing colour quite a difficult feature to use as it can look quite pale on Barn Swallow too, depending on the angle and light.  Of interest and possible relevance this link shows a North American Barn Swallow with a not dissimilar forehead patch and a broadish breast band (admittedly not as broad as Dave's bird).  That link came from a discussion about a brown-backed Barn Swallow on the ID-Frontiers listserve and I see that bird also shows a broad breast band, though it differs from Dave's bird in other ways.  I'd be interested in other people's views about this bird... please use the comments to let us know what you think.



Barn Swallow Hirundo rustica
Cliff Swallow Petrochelidon pyrrhonota

8 comments:

  1. The Vermont bird (the last of the series of photos presented above) is what I would call a typical juvenile Barn Swallow. Especially in South America, but even here in North America, the face of juv Barn Swallows can bleach significantly until they appear nearly white (and the back can turn quite brown). I chalk it up to the juvenile feathers which are of poorer quality than adult plumage, and thus wear and fade more quickly. The VT bird's plumage shows no characters that otherwise disagree with Barn Swallow that I can see.

    -Dan Lane

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    1. Thanks Daniel - that ties in with what I was thinking but good to hear it from someone with more experience of North American taxa.

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  2. I think I have an excellent candidate for Barn x Cliff from Lake Michigan shoreline this past week (5/30/17) - https://flic.kr/s/aHskWkUdQN

    Longer pointed wings like Barn
    Slightly chunkier body like Cliff
    Small forked tail that is too small for Barn, too long and forked for Cliff
    Dark forehead that is like Barn
    Slight white collar like Cliff
    Pale rump like Cliff
    Larger blue crown and face than Cliff, but not as much as Barn
    Primaries and secondaries underwing that look to be darker
    Cleaner undertail coverts more like Barn
    Has some orange wash along he flanks that would be more like Barn

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    1. It does look like a good candidate, doesn't it! Would you mind if we used your photos here?

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    2. Feel free to. It hasn't been approved yet on eBird, FYI.

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  3. My bird was approved. First Michigan report (in eBird) of this hybrid.

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    Replies
    1. Great, thanks for letting us know, and thanks for letting us use your pics too. I'll add some of them here when I next do an update.

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