One of the threats to the BAER’S POCHARD (青头潜鸭) is hybridisation with the closely related, and range expanding, FERRUGINOUS DUCK (白眼潜鸭). At the Baer’s Pochard breeding site in Hebei Province, Ferruginous Duck is a common breeder; I counted more than 60 on site last weekend versus 24 Baer’s.
Another drake, superficially resembling a drake Baer’s, sported a chestnut cap and slightly less white on the flanks than one would expect for a pure Baer’s. It was associating with a group of Ferruginous Ducks and I recorded the video clip below. The chestnut cap is particularly noticeable towards the end of the clip.
I hope to visit the site a few more times over the coming weeks and will look out for more evidence of hybridisation and, hopefully, evidence of breeding Baer’s too.
EDIT: It has been suggested by folks at WWT, who have been catching and taking DNA samples from captive birds, that the drake in the video clip may be a first summer male. Personally, the colour of the cap, resembling the chestnut brown of Ferruginous and not the darker brown typical of Baer’s, makes me think there is some Ferruginous influence but I’ll go back soon and try to get more photos!