Mallard x Spot-billed Duck Anas platyrhynchos x Anas poecilorhyncha

I'd seen pure Spot-billed Ducks at this collection before and carelessly assumed these were the same birds - it was only when I got home and looked at the photos that I realised something wasn't quite right. For the male the extensive yellow on one bill, the curly tail feathers and the faint reddish wash on the breast point to Mallard involvement and I think the female is a hybrid too.

A subsequent visit produced a more Mallard-like bird, but this resembles other published photos of Mallard x Spot-billed Duck hybrids. It seems likely that the original birds were backcrossed with Spot-billed Duck rather than, as I had first assumed, the new bird being backcrossed with Mallard. Thanks to Joern for his input on this.

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captive Spot-billed Duck x Mallard hybrids, possibly backcrossed with Spot-billed Duck, Blakeney Collection (Norfolk, UK), 16th April 2011

 

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captive male Spot-billed Duck x Mallard hybrids, Blakeney Collection (Norfolk, UK), 24th November 2013 - the top left bird may be the same as in the photos above, possiby backcrossed with Spot-billed Duck; the other 3 photos show a single bird

 

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captive male Spot-billed Duck x Mallard hybrid, Blakeney Collection (Norfolk, UK), 22nd February 2014 - probably the same bird as above

 

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captive male Spot-billed Duck x Mallard hybrid, Blakeney Collection (Norfolk, UK), 7th December 2015

 

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captive Spot-billed Duck x Mallard hybrid, possibly backcrossed with Spot-billed Duck, Blakeney Collection (Norfolk, UK), 7th December 2015

 

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captive male Spot-billed Duck x Mallard hybrid, Blakeney Collection (Norfolk, UK), 18th January 2017

 

When I first saw this bird I thought it was likely a young male Mallard showing remnants of juvenile plumage (and bare parts), but when I discovered it (or a very similar bird) six weeks later looking hardly any different I thought a different explanation was required. By this time I had established that the above hybrids were in the collection again (the collection has been recently re-stocked after being destroyed) and the most satisfactory answer seems to be that this is a Spotbill hybrid backcrossed with Mallard.

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captive possible Spot-billed Duck x Mallard hybrid, probably backcrossed with Mallard, Blakeney Collection (Norfolk, UK), 30th October 2015

 

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captive possible Spot-billed Duck x Mallard hybrid, probably backcrossed with Mallard, Blakeney Collection (Norfolk, UK), 7th December 2015