Friday, 11 April 2014

Yellow-billed Duck x Spot-billed Duck

Yellow-billed Duck x Indian Spot-billed Duck hybrid, Hannover Zoo (Germany), 24th October 2012 - copyright Joern Lehmhus
(photo ID: 0587)


Here's Joern's commentary on this bird:
At a first glance, this bird looks close to a Yellowbill, but there are some differences. Yellowbill does not show any facial pattern, but this bird has a weak facial pattern. Indian Spotbill on the other hand has a marked facial pattern.  The uppertail coverts are all black in this hybrid, similar to a Spotbill.  Yellowbill would have pale fringed uppertail coverts.
Note the orange legs of this hybrid, with some dark areas on the toes.  Indian Spotbill has bright orange legs.  Yellowbill legs are dark brownish or blackish with an orange hue, but not bright orange as in this hybrid.
The speculum looks a bit closer to Yellowbill, being too blue for Indian Spotbill, but the white line in font is broader than normal and the white line ending the speculum is fairly thin.  This also seems to indicate Spotbill influence; see the speculum of Indian Spotbill here:
arunachalabirds.blogspot.de/2011/05/indian-spot-billed-du...
The bill pattern is close to Yellowbill, but the upper edge of the upper mandible is yellow-orange, not yellow. This also points to Indian Spotbill as the second parent, as this has a red upper edge of the upper mandible and a yellow tip on a mainly black bill.  The tertials of the hybrid are again closer to Yellowbill in colour and pattern, as they are partly white in Indian Spotbill.
There were two very similar free-flying hybrids so it is not certain whether the photos involve one or both birds.




Yellow-billed Duck x Indian Spot-billed Duck hybrid, Hannover Zoo (Germany), 24th October 2012 - copyright Joern Lehmhus
(photo IDs: 0585-0586)


In the next photo the hybrid is on the left side in the middle ground; in the foreground left is a Yellow-billed Duck and on the right are Indian Spot-billed Duck and Red-crested Pochard.

Yellow-billed Duck x Indian Spot-billed Duck hybrid (with Mallards, Yellow-billed Duck, Indian Spot-billed Duck and Red-crested Pochard), Hannover Zoo (Germany), 24th October 2012 - copyright Joern Lehmhus
(photo ID: 0584)


A pair of similar birds were present in the zoo (but free-flying) in 2014.  Here is the female:




female Yellow-billed Duck x Indian Spot-billed Duck hybrid, Hannover Zoo (Germany), 25th January 2014 - copyright Joern Lehmhus
(photo IDs: 1598-1600)


And here's the male:




male Yellow-billed Duck x Indian Spot-billed Duck hybrid, Hannover Zoo (Germany), 25th January 2014 - copyright Joern Lehmhus
(photo IDs: 1601-1604)


I guess this is the same bird...



Yellow-billed Duck x Indian Spot-billed Duck hybrid, Hannover (Germany), 26th October 2014 - copyright Joern Lehmhus
(photo IDs: 1676-1677)


Yellow-billed Duck Anas undulata
Indian Spot-billed Duck Anas poecilorhyncha

No comments:

Post a comment