Hi Stewart and Tweets,

The high numbers of wigeon at the Fill this week has certainly been a treat. Picking out female Eurasian Wigeons is not too tough, as soon as you see get a chance to study one or two in the field and get a feel for the differences. In general, look closely at the females around the male Eurasians, they tend to stick together. Eurasian females are browner overall, opposed to the gray and pinkish-orange tones in American. They have a with a smaller brown (not gray), square head, and darker eye. They can also be identified by the patterns in the coverts. Cameron Cox and I wrote an article for Birding a couple years ago with all the details on female wigeon identification. It's up online on the ABA website in the Mar/Apr 2005 Birding archives. Here's the link:

http://www.americanbirding.org/pubs/birding/archives/vol37no2p156to164.pdf


The article is based mostly on studying birds at Green Lake. I have not seen a female Eurasian at Green Lake this year, but there is one maybe pure adult male Eurasian and one first-cycle male Eurasian. I say "maybe pure" because the adult male has the most extensive green patch behind the eye I've seen in a Eurasian. It is typical to have a fair amount of green, but this one is a bit beyond what I'd feel comfortable calling a totally pure Eurasian. While its not a F1 American x Eurasian hybrid, it looks like there could be American genes from a couple generations back. As for hybrid females, to my knowledge they are not identifiable in the field, but some individuals are suspicious. There is one female at Green Lake that has been there for two years that Cameron and I think may be a hybrid female. It has a number of intermediate characteristics, but its just too tough to call.

I've never heard a female Eurasian vocalize, but the male calls are quite distinctive. They give a one note, sharply rising whistle, weHEEEEer. It is often louder than American calls, so it can be heard over a noisy flock of Americans.

Good birding,
Jessie Barry
Seattle, WA