Sexing Black Scoter, China (1 Viewer)

[xuky.summer]

I recorded three Black Scoter at Qingdao last sunday. two with yellow bill, are they adult female or first-winter male?
thank you very much!
xuky

 

[Nutcracker]

First-winter male - can also see the first adult black feathers on the tertials & scapulars.

 

[Grahame Walbridge]

They are all 1st-w's xuky. Note paler bellies on all birds; two 1st-w males as 'Nutty' says and a female with its slighter build, paler face + lacking yellow bill.

Grahame.

 

[xuky.summer]

Thank you very much!