Sunday 26 March 2017

Recent updates

Black-headed Gull x Mediterranean Gull hybrid, Christopher Cadbury Reserve, Upton Warren (Worcestershire, UK), 12th March 2017 - copyright John Oates
(photo ID: 3173)


Here's another of our regular posts letting you know what pages have been updated in the project recently.  As always, a big thanks to all who have contributed photos and/or insights, and if you haven't done yet or have more to offer then please get in touch.  You can comment on any thread if you have anything to say about the hybrids or topics covered, and if you have any photos you would be willing for us to use, please let us know (e.g. by emailing us).

The recent updates are summarised below but remember you can find an index list linking you to ALL the bird hybrids featured so far here:
And an index list of all the bird hybrid topics covered so far here:



So, the recent updates are:


New Bird Hybrid page added for:

New photos added to:

Text updated in:


Don't forget you can follow us on Twitter at @BirdHybrids

Enjoy browsing - and please do contribute where you can!

Tufted Duck x Lesser Scaup

Tufted Duck x Lesser Scaup hybrid, Ambleside Duckpond, West Vancouver (British Columbia, Canada), 19th March 2007 - copyright Paul Kusmin
(photo ID: 3144)


It seems pretty clear that this bird is a Tufted Duck x Scaup sp. hybrid but whether Greater or Lesser Scaup is involved is not so straightforward.  The coarseness of the vermiculations on the upperpart is different from at least some Tufted Duck x Greater Scaup hybrids and I think that is very likely to point to Lesser Scaup parentage.  In the two photos (above and below) the darkness of the upperparts looks different - that is often true in Tufted Duck x Scaup sp. hybrids, varying according to light and angle to the observer.

Tufted Duck x Lesser Scaup hybrid (same bird as in photo ID 3144 above), Ambleside Duckpond, West Vancouver (British Columbia, Canada), 16th March 2007 - copyright Paul Kusmin
(photo ID: 3145)


Tufted Duck x Lesser Scaup was the suggested ID for the following bird on the other side of the Atlantic (Tufted Ducks are vagrants among Lesser Scaup in North America while Lesser Scaups are vagrants among Tufted Ducks in Europe, so the hybrid is just as likely to occur on either continent).  The identification of this bird was discussed but I couldn't see that any clear conclusions were reached - as always, comments welcome.  There is also a video of this bird on YouTube.

possible Tufted Duck x Lesser Scaup hybrid, Møllekrogen (Denmark), 14th October 2016 - copyright Rasmus Strack
(photo ID: 3065)



Tufted Duck Aythya fuligula
Lesser Scaup Aythya affinis

Thursday 2 March 2017

Recent updates

apparent Great Blue Heron x Great Egret hybrid, Fort de Soto Park, Pinellas County (Florida, USA), 17th August 2016 - copyright Dave Norgate
(photo ID: 2976)


At last I have managed to clear nearly all of the backlog of photos waiting to be uploaded here since my previous update, far too long ago.  Below is a summary of what's gone in.

As always, a big thanks to all who have contributed photos and/or insights, and if you haven't done yet or have more to offer then please get in touch.  You can comment on any thread if you have anything to say about the hybrids or topics covered, and if you have any photos you would be willing for us to use, please let us know (e.g. by emailing us).

The recent updates are summarised below but remember you can find an index list linking you to ALL the bird hybrids featured so far here:
And an index list of all the bird hybrid topics covered so far here:



So, the recent updates are:


New Bird Hybrid pages added for:

New photos added to:

Text updated in:


Don't forget you can follow us on Twitter at @BirdHybrids

Enjoy browsing - and please do contribute where you can!

Dunlin x White-rumped Sandpiper

Dunlin x White-rumped Sandpiper hybrid, Rock Point Provincial Park (Ontario, Canada), 19th May 2016 - copyright Chris Cheatle
(photo ID: 2931)


There have now been quite a range of hybrid shorebirds recorded but this is the first calidrid hybrid we have featured in the Bird Hybrids project.  Hopefully others will follow soon...

Apparently Chris's excellent set of photos were reviewed by two published shorebird authors, an OFO (Ontario Federation of Ornithologists) and EBird reviewer and confirmed as this combination by all. This spring bird appears to be in breeding plumage - juveniles moult out of juvenile plumage during their first winter and the patterning and freshness of the feathers in May mean these are not retained non-breeding feathers.  Once that is understood it becomes clear that no pure species fits the bill.  The head pattern and the breast spotting running down the foreflanks recalls White-rumped Sandpiper whereas the rufous in the scapulars is too extensive for that species.  The bill is intermediate between the two species and Chris reports that the rump was generally white.








Dunlin x White-rumped Sandpiper hybrid (same bird as in phtoo ID 2931 above), Rock Point Provincial Park (Ontario, Canada), 19th May 2016 - copyright Chris Cheatle
(photo IDs: 2932-2939)



Dunlin Calidris alpina
White-rumped Sandpiper Calidris fuscicollis

Wednesday 1 March 2017

Black-bellied Whistling-Duck x Fulvous Whistling-Duck

Black-bellied Whistling-Duck x Fulvous Whistling-Duck hybrid, Moon Lake, Progreso Lakes, Hidalgo County (Texas, USA), 28th December 2016 - copyright Daniel Jones
(photo ID: 2998)


Hybrids between various species of Whistling-Duck seem to crop up quite frequently in captivity but wild-bred Whistling-Duck hybrids seem to be much more unusual.  This bird has the dark chestnut upperparts of Black-bellied with subtle pale tips to the feathers that are intermediate between the two species (plain on Black-bellied, clearly barred on Fulvous).  The dull head, the bill and legs lacking bright colours and the lack of a black belly are all possible on a young Black-bellied Whistling-Duck, but that cannot be the explanation here as the belly is also distinctly orange.  The vent (beneath the tail) is white, like Fulvous, and the black marks on the foreneck also recall those on a Fulvous Whistling-Duck.  Daniel's flight photos also reveal that this bird is missing the pale stripe through the centre of the upperwing that is found on Black-bellied Whistling-Duck





Black-bellied Whistling-Duck x Fulvous Whistling-Duck hybrid (same bird as in photo ID 2998 above; with Black-bellied Whistling-Ducks), Moon Lake, Progreso Lakes, Hidalgo County (Texas, USA), 28th December 2016 - copyright Daniel Jones
(photo IDs: 2999-3003)



Black-bellied Whistling-Duck Dendrocygna autumnalis
Fulvous Whistling-Duck Dendrocygna bicolor

Greater White-fronted Goose x Lesser White-fronted Goose

probable Greater White-fronted Goose x Lesser White-fronted Goose hybrid, Oudeland van Strijen (Zuid-Holland, Netherlands), 22nd February 2015 - copyright Diederik Kok
(photo ID: 3010)


There is quite a lot of variation in both Greater and Lesser White-fronted Geese so proving hybrids between them is quite difficult.  I am not entirely certain that pure Greater White-fronted Goose can be discounted for this individual as there probably isn't any single feature shown by this bird that does not sometimes appear on them.  However the combination of conspicuous yellow eye-ring, limited dark belly markings and slightly short-looking very pink bill make me think it is a good candidate.  There isn't much in the size or structure visible in the photos to clinch it though, so I am a bit cautious about labelling this as a definite hybrid.


probable Greater White-fronted Goose x Lesser White-fronted Goose hybrid (with Greater White-fronted Geese; same bird as in photo ID 3010 above), Oudeland van Strijen (Zuid-Holland, Netherlands), 22nd February 2015 - copyright Diederik Kok
(photo IDs: 3011-3012)



Greater White-fronted Goose Anser albifrons
Lesser White-fronted }Goose Anser erythropus

Tunrda Bean Goose x Barnacle Goose

Tunrda Bean Goose x Barnacle Goose hybrid (with Tundra Bean Geese), Oost (Texel, Netherlands), 30th December 2016 - copyright Diederik Kok
(photo ID: 3006)


The pale cheek with a reddish brown lower rear section reminds me of some Red-breasted Goose hybrids but I don't think that can be the case here.  I've never seen Tundra Bean x Red-breasted but based on how White-fronted Goose x Red-breasted Goose hybrids look I would expect a darker body and a more obviously smaller bird.  So I think Barnacle Goose seems the better solution for the white-cheeked parent.  It would be difficult to say for sure what the grey goose parent was but the fact that it is surrounded by Tundra Bean Goose makes that a pretty good bet - and the bright orange legs and pale belly are certainly consistent with that.



Tundra Bean Goose Anser serrirostris (formerly Anser fabalis rossicus)
Barnacle Goose Branta leucopsis

Tundra Bean Goose x Greater White-fronted Goose

probable Tundra Bean Goose x Greater White-fronted Goose hybrid (with Tundra Bean Geese), Oost (Texel, Netherlands), 29th December 2016 - copyright Diederik Kok
(photo ID: 3004)


Convincing examples of hybrids between some of the wild Anser species that occur in Europe are surprisingly hard to come by.  Perhaps that is because the hybrids are genuinely scarce, or perhaps it is hybrids are difficult to detect and even harder to prove, with variation in parent species considerable.  I suspect it's the latter but maybe in time this will become more clear.  This one looks like a promising candidate to me, although proving it is not an odd but genetically pure Tundra Bean Goose is not straightforward.

The white round the base of the bill is not enough on its own to reject pure Tundra Bean Goose - quite often they have a little white round the bill.  Usually this is broken on pure birds, not surrounding the whole of the upper mandible in a continuous line.  Not only is it continuous here but it's quite broad at the top too.  Perhaps that is possible in pure Tundra Bean - it wouldn't surprise me if so - but this bird also has a lot of dark shading behind the white, something that I don't recall seeing to this extent on a Tundra Bean Goose.  The extent of orange on the bill may not be too excessive for Tundra Bean Goose (though is not usual) but it also seems to have a pinky tone to it.  I think in combination these features point to a likely hybrid origin, although I am troubled by how perfect the rest of the bird looks for Tundra Bean Goose.  Maybe it is just a very unusual Tundra Bean Goose, but I am more convinced by this bird being a hybrid than others I've seen where the hybrid ID has been suggested.

In addition Diederik thought this bird called differently from the Tundra Bean Geese.  He has a recording of it at waarneming.nl.  I think it's quite a subtle difference, but that may be because I don't hear Tunrda Bean Geese calling often enough!

As always, comments are welcome!

probable Tundra Bean Goose x Greater White-fronted Goose hybrid (same bird as in photo ID 3004 above; with Tundra Bean Geese), Oost (Texel, Netherlands), 29th December 2016 - copyright Diederik Kok
(photo ID: 3005)



Tundra Bean Goose Anser serrirostris (formerly Anser fabalis rossicus)
Greater White-fronted Goose Anser albifrons

Great Blue Heron x Great Egret

Great Blue Heron x Great Egret hybrid, Fort de Soto Park, Pinellas County (Florida, USA), 17th August 2016 - copyright Dave Norgate
(photo ID: 2976)


The long kinked neck of this intriguing bird is very much like that of a Great Egret, but in other respects the structure of this bird seems to resemble Great Blue Heron as much.  The grey plumage and the bill do not belong on a Great Egret, whereas the yellow lores must come from an Egret species.  The latter, along with the neck structure, help rule out Würdemann's Heron (the hybrid or intergrade between Great White Heron (the white form occidentalis of Great Blue Heron that occurs in southernmost Florida) and typical Great Blue Heron.

Thanks to Steve Mlodinow for pointing out that this bird has been accepted as this hybrid by eBird reviewers and photographed by other observers over six months.










Great Blue Heron x Great Egret hybrid (same bird as in photo ID 2976 above), Fort de Soto Park, Pinellas County (Florida, USA), 17th August 2016 - copyright Dave Norgate
(photo IDs: 2977-2986)



Great Blue Heron Ardea herodias
Great Egret Ardea alba

Common Goldeneye x Hooded Merganser

Common Goldeneye x Hooded Merganser hybrid, Ottawa River (Ontario, Canada), 26th October - copyright Gordon Johnston
(photo ID: 2997)


Goldeneye sp. x Hooded Merganser hybrids are fairly frequently reported in the wild and broadly speaking this is a typical plumage for either.  The majority of reports probably relate to Common Goldeneye x Hooded Merganser.  The head colour seems to reflect that of the Goldeneye parent species at least in many instances, but you can't really make that out here.  However the extent of white in the scapulars helps clinch this one as involving Common Goldeneye rather than Barrow's Goldeneye.

We already have a page featuting a probable female Goldeneye sp. x Hooded Merganser which, in view of the extent of yellow on its bill is possibly more likely to involve Barrow's Goldeneye.


Common Goldeneye Bucephala clangula
Barrow's Goldeneye Bucephala islandica
Hooded Merganser Lophodytes cucullatus

Great Egret x Snowy Egret

Great Egret x Snowy Egret hybrid, Fort de Soto Park, Pinellas County (Florida, USA), 18th August 2016 - copyright Dave Norgate
(photo ID: 2987)


Dave says this bird seemed intermediate in size between Great Egret and Snowy Egret.  Structurally it seems to have an intermediate neck length and shape - you can see a hint of the kinked shape of Great Egret in some of the photos but it's not as clear as in a pure bird.  The bare parts also seem to be consistent with expectations for this hybrid.  Certainly the legs are wrong for Snowy Egret being entirely black right down to the bottom of the feet.  The gape line only extends back to below the cetnre of the eye, just like it does on Snowy Egret.  On Great Egret it would extend right back to beyond the back of the eye.  The only pure species I could possibly turn this into is Intermediate Egret, which in some respects it quite closely resembles.  However, although the Asian form of Intermediate Egret apparently does adopt a black bill in breeding condition (I don't believe the African form does) this bird is showing no sign of being in breeding condition.  I don't think the bill structure is quite right for Intermediate Egret either, and of course an Asian Intermediate Egret is rather unlikely in Florida - there are one or two ABA-area records but only from the Aleutian Islands in western Alaska so far as I know.




Great Egret x Snowy Egret hybrid (same bird as in photo ID 2987 above), Fort de Soto Park, Pinellas County (Florida, USA), 18th August 2016 - copyright Dave Norgate
(photo IDs: 2988-2991)



Great Egret Ardea alba
Snowy Egret Egretta thula