Saturday, 19 April 2014

Common Pochard x Tufted Duck

Common Pochard x Tufted Duck hybrid, Barry (Glamorgan, UK), 9th November 2016 - copyright Thomas Winstone
(photo ID: 3066)


This is probably the commonest duck hybrid in the UK, though the majority of records are of males.  The next one is a female and seems to be quite a typical individual.

Common Pochard x Tufted Duck hybrid, Killingworth Lake (North Tyneside, UK), 21st January 2016 - copyright Tom Tams
(photo ID: 2611)


The range of variation in females is not yet entirely clear and some individuals seem to be much trickier.  As with all hybrids in this project, please contribute any more photos you have so that we can build a clearer picture.  David Darrell-Lambert has done just that and I'm pleased to present a great selection of his photos below, showing a bit of variation among his females.  Always room for more though...


Common Pochard x Tufted Duck hybrids, Hyde Park (Greater London, UK), 2nd February 2015 - copyright David Darrell-Lambert
(photo IDs: 2682-2683)



Common Pochard x Tufted Duck hybrid, Finsbury Park (Greater London, UK), 13th March 2011 - copyright David Darrell-Lambert
(photo IDs: 2680-2681)



Common Pochard x Tufted Duck hybrid, Hyde Park (Greater London, UK), 9th December 2011 - copyright David Darrell-Lambert
(photo IDs: 2685-2686)


Common Pochard x Tufted Duck hybrid, Victoria Park (Greater London, UK), 7th March 2015 - copyright David Darrell-Lambert
(photo ID: 2684)


Common Pochard x Tufted Duck hybrid, St James's Park (Greater London, UK), 8th February 2007 - copyright David Darrell-Lambert
(photo ID: 2675)



Common Pochard x Tufted Duck hybrid, St James's Park (Greater London, UK), 3rd April 2007 - copyright David Darrell-Lambert
(photo IDs: 2676-2677)


Common Pochard x Tufted Duck hybrid (with Common Pochards), Thorpe Park (Surrey, UK), 28th February 2009 - copyright David Darrell-Lambert
(photo ID: 2678)


Common Pochard x Tufted Duck hybrid, Thorpe Park (Surrey, UK), 9th December 2010 - copyright David Darrell-Lambert
(photo ID: 2679)


This one from the north of England is, I presume, the same bird as shown at the top of this page (photo ID 2611)...



Common Pochard x Tufted Duck hybrid, Killingworth Lake (North Tyneside, UK), 16th January 2016 - copyright Chris Knox
(photo IDs: 2604-2605)


Males can be relatively easy to recognise, though having said that it's not unusual for these to be erroneously reported as vagrant Lesser Scaups. The reddish colour on the head can be hard to make out and seems to vary in intensity between individuals.  If in doubt about eliminating Lesser Scaup check the bill pattern, the eye-colour and the body - Lesser Scaup has much more coarsely vermiculated upperparts and less obviously grey flanks.




Common Pochard x Tufted Duck hybrid (with Tufted Duck), Swanton Morley (Norfolk, UK), 27th December 2008 - copyright Dave Appleton
(photo IDs: 0467-0470)


The next bird seems to show a more obviously reddish head than any examples of this hybrid that I've seen before, and the back looks a bit paler too.  I suppose it's plausible that it's a backcrossed bird but I guess it's simply within the range of variation for this hybrid?  Henry tells us that the orangey eye visible in the photos was evident in all light conditions, and distinct from the red-eyed Pochard.  Nice to get a good look at the wings here too.



Common Pochard x Tufted Duck hybrid, Espoo (Finland), 19th May 2009 - copyright Henry Lehto
(photo IDs: 2533-2535)



Common Pochard x Tufted Duck hybrid (presumably same bird as in photo IDs 0467-0470 above), Swanton Morley (Norfolk, UK), 30th December 2008 - copyright Dave Appleton
(photo IDs: 0471-0472)


Common Pochard x Tufted Duck hybrid, Welney (Norfolk, UK), 2nd January 2005 - copyright Dave Appleton (photo ID: 0473)


Another female that seems to be typical from what we have learned so far:

Common Pochard x Tufted Duck hybrid, River Enz, Pforzheim-Eutingen (Germany), 25th February 2005 - copyright Joern Lehmhus
(photo ID: 0716)


In his photos of what is apparently the same bird there's a slight bluish cast which Joern tells us was not present in life.




Common Pochard x Tufted Duck hybrid (same bird as in plate ID 0716 above), River Enz, Pforzheim-Eutingen (Germany), winter 2005/06 - copyright Joern Lehmhus
(photo IDs: 0839-0842)


Andy Warr emailed the project with some images of a hybrid female.  Based on the head shape, the extent of pale in the head and the grey wing-bar he wondered if it might be Pochard x Ring-necked Duck.  I have no experience of such a hybrid - not even males - and can conceive that it might match this bird's appearance.  But I'm not sure whether any of these features are beyond the range shown by Pochard x Tufted Duck.  That would of course be a more likely answer, but does it fit this bird's appearance?  Let us know what you think!





possible Common Pochard x Tufted Duck hybrid (with Common Pochards and Tufted Ducks), Ripple (Worcestershire, UK), 4th October 2015 - copyright Andy Warr
(photo IDs: 2370-2374)


Another drake:


Common Pochard x Tufted Duck hybrid (with Common Pochard), Titchwell (Norfolk, UK), 8th February 2014 - copyright Dave Appleton
(photo IDs: 1752-1753)


The next one may have been the same bird, returning for another winter.





Common Pochard x Tufted Duck hybrid (with Common Pochard), Titchwell (Norfolk, UK), 3rd January 2015  - copyright Dave Appleton
(photo IDs: 1747-1751)


The identity of the next bird is not altogether clear. It was not seen in good light and it is difficult to tell from the photos what the true colour of the back was. If it was as black as it looks in some photos then it is surely a pure Tufted Duck, but if it is as grey as it looks in others then it must be a hybrid.  One strong possibility is that it is a Pochard x Tufted Duck hybrid backcrossed with Tufted Duck.









 
possible (Common Pochard x Tufted Duck) x Tufted Duck backcrossed hybrid, Utterslev Mose (Copenhagen, Denmark), late February 2008 - copyright Lars Michael Nielson 
(photo IDs: 0890-0897)


The next one seems to be a typical female hybrid:


Common Pochard x Tufted Duck hybrid (with Tufted Ducks and Common Pochard), Stege slambassiner (Moen Denmark), 18th February 2006 - copyright Rasmus Strack
(photo IDs: 0908-0909)


The next female is not identified.  To me it resembles other examples of Common Pochard x Tufted Duck hybrid but Lars Michael Nielson who was with Rasmus when the photos were taken explains why he thinks it might not be:
"The bird was in a mixed flock of Aythya ducks, mostly Tufted Ducks but also some Common Pochards and Greater Scaups. In the field, the birds was clearly larger than the Tufted Ducks, intermediate between Pochard and Tufted.  The head shape is not as 'edgy' as the other female Pochard x Tufted Ducks above and the brown parts of the bird are not as dark as well. Furthermore the colour of the back and flanks is more similar in colour comparing to the other females. At first this made us think of Pochard x Scaup, but the overall shape and colour of the bird does not fit very well with that combination. We then thought backcross to Pochard as a possibility but again we have no experience with such backcrosses. We have also been talking of involvement of other Aythya species such as Redhead or Ring-necked Duck but havent been able to find any pictures of female hybrids involving theese species. When the bird flew it showed all grey wings, further indicating that this bird might not be an F1 hybrid Pochard x Tufted Duck, or involvement of Ring-necked Duck. I belive that the identity of this bird might comtinue to be a mystery. I have read the text in the Gillhams' book and actually find some similarities to the female hybrid Canvasback x Ring-necked Duck (Number 128)."
Lars welcomes comments, as we always do!


unidentified Aythya hybrid, possibly Common Pochard x Tufted Duck hybrid (with Tufted Ducks), Stege slambassiner (Moen Denmark), 3rd February 2007 - copyright Rasmus Strack
(photo IDs: 0901-0902)


Next is another one where the identity is a bit of a mystery.  One contender, and my reason for including it in this thread, is backcrossed (Common Pochard x Tufted Duck) x Tufted Duck.  That could explain the darker back than on typical Common Pochard x Tufted Duck hybrid, but it's far from certain.





unidentified Aythya hybrid, possibly (Common Pochard x Tufted Duck) x Tufted Duck backcrossed hybrid, Utterslev mose (Denmark), April 2008 - copyright Rasmus Strack
(photo IDs: 0885-0889)


A tricky female Aythya hybrid I photographed in Cornwall previously featured on this page as a 'possible' Pochard x Tufted Duck hybrid.  I remain uncertain about its identity but am now favouring Pochard x Ferruginous Duck.  For that reason I have moved the photos to the page for Common Pochard x Ferruginous Duck hybrids.  However I am still not 100% convinced that Pochard x Tufted Duck is ruled out, so I will continue to refer to it here too, leaving just one of the photos here for now:

possible Common Pochard x Ferruginous Duck (or perhaps x Tufted Duck) hybrid, Gwithian Sands (Cornwall, UK), 19th November 2013 - copyright Dave Appleton 
(photo ID: 0476)


This male has been present for at least 5 years at Thurlby, Whisby and Norton Disney gravel pits in Lincolnshire (UK).  Though it has been identified by optimistic birders as a Lesser Scaup on a number of occasions, it is a typical Pochard x Tufted Duck hybrid.  Dean tells us that it is always found with Tufted Ducks, never Pochards.  Apparently it usually pairs with Tufted Ducks but no young have been detected, so presumably it is either infertile or any backcrossed young are so similar to Tufted Duck so as to be undetectable.





Common Pochard x Tufted Duck hybrid, Thurlby, Whisby or Norton Disney gravel pits (Lincolnshire, UK), no date supplied - copyright Dean Nicholson
(photo IDs: 2637-2641)




Common Pochard x Tufted Duck hybrid, Thurlby Gravel Pit (Lincolnshire, UK), no date supplied - copyright Dean Nicholson
(photo IDs: 2642-2644)


Another easy one...


Common Pochard x Tufted Duck hybrid, no location given (probably UK), 12th March 2016 - copyright Philip Ridsdale
(photo IDs: 3092-3093)


Structurally the next bird was much like a Pochard and it had grey Pochard-like wing-bars.  I considered the possibility that it was just an aberrant Pochard, but I don't think so - it also had a less contrasting dark breast than other female Pochards there and the bill pattern wasn't normal.  As seen above female Pochard x Tufted Duck hybrids typically show a white face, more extensive than is usually present on either parent species, but this was the same size as Pochard, had a darker bill than most Pochard x Tufted females and a more restricted pale subterminal band, and it lacked any hint of a tuft.  In some ways it was quite like the bird above seen by Lars and Rasums (photo IDs 0901-0902) - not fully resolved but perhaps a Pochard x Tufted Duck hybrid backcrossed with Pochard.  I also considered Pochard x Scaup, a combination I have never come across before, but I' suspect not.  Thoughts welcome!












possible Common Pochard x Tufted Duck hybrid, Welney (Norfolk, UK), 4th February 2017 - copyright Dave Appleton
(photo IDs: 3114-3123)


The next set of photos were taken at the same place as photo IDs 2370-2374 above and it's possible that it's the same returning bird.  There does seem to be a hint of Ring-necked head shape in one or two of the photos but on balance I'm favouring Pochard x Tufted Duck again.







probable Common Pochard x Tufted Duck hybrid (with Common Pochards), Ripple Pits (Worcestershire, UK), 9th March 2017 - copyright Andy Warr
(photo IDs: 3176-3182)


Joern Lehmhus has written about Common Pochard x Tufted Duck hybrids in the German magazine Aves.  The text is in German but non-German speakers may still be interested as it's accompanied by a number of photos of Common Pochard x Tufted Duck hybrids.  You can access the PDF of Aves 3 (2012) - scroll down to page 32 - the nine photos captioned "Reiherente x Tafelente" are Common Pochard x Tufted Duck hybrids.



Common Pochard Aythya ferina
Tufted Duck Aythya fuligula

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