Marko Matesic/ BIA / Ferruginous Duck (Aythya nyroca) pair on pond, Krk, Croatia

Marko Matesic/ BIA / Ferruginous Duck (Aythya nyroca), Krk, Croatia

Dong Lei / Baer's pochard (Aythya baeri) with White-eyed pochard (Aythya nyroca) Chengdu City, Sichuan Province, China.

Dong Lei / Mixed group of Baer's pochards (Aythya baeri) with White-eyed Pochards (Aythya nyroca) Chengdu City, Sichuan Province, China.

Ralph Martin / Ferruginous Duck (Aythya nyroca), Baden-Wurttemberg, Germany

Duncan Usher / Ferruginous Duck (Aythya nyroca) male, Bavarian Forest, Bavaria, Germany

Martin Willis / Ferruginous Duck (Aythya nyroca) males and females, Yunnan Province, China

Joel Sartore / Photo Ark / Ferruginous ducks (Aythya nyroca) pair, portrait, Sylvan Heights Bird Park. Captive.

Joel Sartore / Photo Ark / Ferruginous duck (Aythya nyroca) male, head portrait, Sylvan Heights Bird Park. Captive.

Joel Sartore / Photo Ark / Ferruginous duck (Aythya nyroca) male, portrait, Sylvan Heights Bird Park. Captive.

Joel Sartore / Photo Ark / Ferruginous duck (Aythya nyroca) male, portrait, Palm Beach Zoo. Captive.

Joel Sartore / Photo Ark / Ferruginous duck (Aythya nyroca) male, head portrait, Palm Beach Zoo. Captive.