How can I tell the difference between Eurasian Wigeon (Mareca Penelope) female and American Wigeon (Mareca Americana) female ? (1 Viewer)

[Xelioszzapporro!!]

That's the 3rd thread in order to differentiate female duck species with one another , which look to me indistinguishable and I am basically asking for help in order to find out how to tell them apart....this time it's wigeon.....I really don't know how I can tell apart an Eurasian Wigeon with an American Wigeon....

If somebody knows please tell me...

@Bewick @Alexander Stöhr @jurek @Southern Viking @nartreb @Stephen Dunstan @Harrybongo

 

[aeshna5]

Very similar. No doubt many get overlooked. Seeing the axillaries is probably the best feature, which is white in americana & greyish in penelope. Trouble is this isn't always easy to determine & can look whitish in the latter species.