Tuesday 17 June 2014

Red-crested Pochard x Common Pochard

Red-crested Pochard x Common Pochard hybrid, Botshol (The Netherlands), March 2016 - copyright Roy Slaterus
(photo ID: 2741)

I suppose this smart hybrid could be overlooked among Pochards given a cursory look, but on closer inspection the identity is clear.  The bill shape and head shape recall Red-crested Pochard while there is a hint of the red bill colour and orange head colour (especially on the crown).  And the smooth grey upperparts contrasting with the whitish-grey flanks are unlike those of Common Pochard.  The angle of the rear edge of the breast seems intermediate.  Note that both this bird and the next one show a diffuse but distinctly paler area on the upper scapulars.  To me this looks almost like a reflection giving it a metallic look, but maybe that is only in photos?

Dean tells us that the next bird was present for just one day among an influx of Common Pochard, normally a scarce bird at this site.  When he first saw it asleep among the Pochard he noticed its slightly larger size, that it was sitting higher in the water and had a darker mantle.  I can imagine thoughts of vagrant Redhead whizzing through Dean's head but he was quick to realise that there was a less salubrious (but equally interesting) explanation.  With better views and sustained observation Dean noted the following:
  • Bulkier than Pochard; bigger more rounded head with steep forehead and with rounded rear crown;
  • Bill was mainly pale red/pink with a dark nail and dark base, closer in shape to Red-crested Pochard;
  • In flight (see photo ID 2636 below) the large and broad white wing bars are very conspicuous compared to the Pochards, also white leading edge and scapulars; underwing was very white;
  • Darker grey/brown mantle contrasting strongly with white flanks; the mantle was also paler directly behind the neck where drake Red-crested Pochards have a small white patch;
  • Subtly paler brown (with orange tint) head more obvious in the field than the photos depict;
  • The black breast was similar to Pochard but in direct comparison was slightly more extensive running back on to the flanks slightly further, especially at the bottom near the water line.  

Red-crested Pochard x Common Pochard hybrid (with Common Pochards), Fillingham Lake (Lincolnshire, UK), 18th February 2014 - copyright Dean Nicholson
(photo IDs: 2625-2636)

The next one was found by Lars Michael Nielson and was believed to be the first such hybrid to be seen in Denmark.

Red-crested Pochard x Common Pochard hybrid, Lake Roegboelle, Lolland (Denmark), 2nd October 2005 - copyright Rasmus Strack
(photo ID: 0898)

Although there is no red apparent in the bill the next bird is very similar to Dean's above.

Red-crested Pochard x Common Pochard hybrid (with Tufted Ducks), Biddinghuizen (Flevoland, Netherlands), 18th January 2015 - copyright Diederik Kok
(photo IDs: 3013-3014)

I presume this is the same bird:

Red-crested Pochard x Common Pochard hybrid (with Tufted Duck), Biddinghuizen (Flevoland, Netherlands), 11th January 2015 - copyright Diederik Kok
(photo ID: 3015)

The next bird is quite similar apart from some brown feathers in the flanks but it has distinct reddish tones to the bill.

Red-crested Pochard x Common Pochard hybrid (with Common Pochards and Tufted Ducks), Veluvemeer (Flevoland, Netherlands), 21st December 2014 - copyright Diederik Kok
(photo IDs: 3016-3021)

One more from the UK...

Red-crested Pochard x Common Pochard hybrid, JCB Lakes, Rocester (Staffordshire, UK), 11th April 2017 - copyright Philip Ridsdale
(photo IDs: 3197-3199)

Joern Lehmhus has written about Red-crested Pochard x Common Pochard 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 couple of photos of Red-crested Pochard x Common Pochard hybrids.  You can access the PDF of Aves 4 (2013) - the article starts on page 21 with section 2.3 on this hybrid beginning at page 24 - the two photos captioned "Tafelente x Kolbenente" are Red-crested Pochard x Common Pochard hybrids.

Red-crested Pochard Netta rufina
Common Pochard Aythya ferina

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