Thursday, 17 April 2014

Blue-winged Teal x Northern Shoveler

Blue-winged Teal x Northern Shoveler hybrid, Titchwell (Norfolk, UK), 7th April 2001 - copyright Dave Appleton
(photo ID: 0383)


A large proportion of vagrant Blue-winged Teals in spring in Europe are found consorting with Northern Shovelers, so the occurrence of this hybrid is not entirely unexpected.  The above individual was first seen in April 2000 but identified then as an escaped Australian Shoveler.  That error was understandable as this hybrid does closely resemble that species (which occurred in captivity in north Norfolk).  John Kemp, who later discovered and correctly identified it in November 2000, described the differences in an article published in Birding World 13: 460-461.  Structurally he noted that it was slightly less heavy and smaller-headed than both Shoveler species, and with a shorter slimmer bill that was narrower in side profile with less of a 'grinning patch'.  The eyes were dark, unlike Australian and Northern Shovelers which both have yellow eyes, and John described the legs as "rich yellow, not as orange as in Shoveler".

The hybrid occurs fairly often in North America where of course both species are common.  Picking out a female hybrid is a much more impressive, but Steve seems to have done just that - more than once!  The first shot of one below looks a lot like a Blue-winged Teal with a Shoveler's bill!  Steve notes that the relatively cool colour tones make Blue-winged Teal more likely than Cinnamon Teal as one parent.

apparent Blue-winged Teal x Northern Shoveler hybrid, Ish Reservoir, Larimer County (Colorado, USA), 24th March 2011 - copyright Steve Mlodinow
(photo ID: 1443)

In the next two photos you can clearly see the small size - Steve tells us it that it was nearly as small as a Blue-winged Teal.  He adds:
"Note the jet black bill, which would be very unusual for a female N Shoveler this time of year. The head pattern is reminiscent of BW Teal, but is shown by a minority of female N Shovelers. Also, the birds compact jizz is that of a teal, which is what I thought it was on initial glance. The bill is not dramatically different in shape from that of a Shoveler, but seems subtly so."

apparent Blue-winged Teal x Northern Shoveler hybrid (same bird as in photo ID 1443 above; with Northern Shoveler and Gadwall), Ish Reservoir, Larimer County (Colorado, USA), 24th March 2011 - copyright Steve Mlodinow
(photo IDs: 1441-1442)


Steve managed to get some good flight shots of this bird and draws our attention to the white trailing edge to secondaries and pale belly, more typical of Blue-winged Teal than Shoveler. and the limited dark leading edge to underwing coverts, classic for Northern Shoveler. The white bar anterior to the speculum is like that of Shoveler.  In these photos the bill appears a bit smaller than that of male Shoveler, though this is hard to assess. The leg colour seems more like that of Northern Shoveler.


apparent Blue-winged Teal x Northern Shoveler hybrid (same bird as in photo IDs 1441-1443 above; with Northern Shoveler), Ish Reservoir, Larimer County (Colorado, USA), 24th March 2011 - copyright Steve Mlodinow
(photo IDs: 1439-1440)


Steve's next one was quite similar.  He describes how it was in between Cinnamon Teal and Northern Shoveler in size, though closer to the teal in that regard.  Its face pattern was like that of a Blue-winged Teal, but not quite as prominent.  The eye showed yellow (yellow-orange?).  The bill was hefty and black, looking much like a Shoveler's in size and shape, though a bit less spatulate (clearly more so than nearby Cinnamon Teal).  In the end, the bird looked like a small Shoveler, with a proportionately smallish bill, very black bill (which some Shovelers will show, though not commonly) and a somewhat Blue-winged Teal-like face pattern (not as evident in these photos as in the field).  The bird was viewed for many minutes near Cinnamon and Blue-winged Teals and looked a bit larger than these photos suggest.




apparent Blue-winged Teal x Northern Shoveler hybrid, El Tanque, Chametla (Baja California Sur, Mexico), 5th November 2012 - copyright Steve Mlodinow
(photo IDs: 1246-1249)


The next bird was in captivity. Also in the collection were single drake Cinnamon Teal and Blue-winged Teal (the latter apparently a first-winter). On my first visit this was all I saw so this bird could have been paired with either (most birds in the recently re-stocked collection were young pairs), though on a subsequent visit I found a female Cinnamon Teal and also observed this bird keeping company with the drake Blue-winged Teal.

Apart from its bill the bird closely resembled Blue-winged Teal but when I looked at the photos after the first visit I thought the bill looked too spatulate. I considered whether it could instead be Cinnamon Teal, or a hybrid between the two species. The head pattern appears to rule out pure Cinnamon Teal and the colour on the bill seems wrong for either Blue-winged or Cinnamon Teal or, presumably, a hybrid between the two. Moreover I thought the bill was perhaps too spatulate even for Cinnamon Teal, so the most satisfactory explanation seemed to be Shoveler x Blue-winged Teal.



captive possible Blue-winged Teal x Shoveler hybrid, Blakeney Collection (Norfolk, UK), 7th December 2015 - copyright Dave Appleton
(photo IDs: 2409-2411)

But on my next visit this bird - at least I'm fairly sure it was the same bird - appeared rather different to how it seemed from the photos the first time round. The bill didn't look so spatulate and the colour on it was more subtle. Could this be a pure Blue-winged Teal after all?  Comments welcome!



captive possible Blue-winged Teal x Shoveler hybrid, Blakeney Collection (Norfolk, UK), 23rd December 2015 - copyright Dave Appleton
(photo IDs: 2429-2431)


Further views the following year haven't really helped very much...

captive possible Blue-winged Teal x Shoveler hybrid, Blakeney Collection (Norfolk, UK), 26th October 2016 - copyright Dave Appleton
(photo ID: 2833)


captive possible Blue-winged Teal x Shoveler hybrid, Blakeney Collection (Norfolk, UK), 3rd December 2016 - copyright Dave Appleton
(photo ID: 2834)



captive possible Blue-winged Teal x Shoveler hybrid, Blakeney Collection (Norfolk, UK), 18th January 2017 - copyright Dave Appleton
(photo IDs: 2835-2836)


The next bird has a more clearly spatulate bill which should have rung alarm bells, but nevertheless it masqueraded as a vagrant Blue-winged Teal for a couple of days before its hybrid identity was clocked (at least it was reported on the rare bird news services simply as a Blue-winged Teal into its third day before being corrected).




Blue-winged Teal x Northern Shoveler hybrid, Grimley (Worcestershire, UK), 28th August 2014 - copyright Andy Warr
(photo IDs: 2439-2442)


This same bird reappeared the following autumn when it had developed a more prominent pale loral spot.  Notice how obvious the colour on the bill is when seen from underneath!







Blue-winged Teal x Northern Shoveler hybrid, Grimley (Worcestershire, UK), 26th September 2015 - copyright Andy Warr
(photo IDs: 2443-2449)



Blue-winged Teal Anas discors
Northern Shoveler Anas clypeata

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