Strange how green-winged teal keeps turning up in March every year at the moment - this one is still on site today and apparently displaying to the other teals! I suspect the run of records is the same bird but then birds never quite do things that you think they should, it could just as easily be a different bird every time!
Funny but they often say American green-winged teal but in reality they do nest over into Asia as I discovered when I went over to Siberia this summer, although I didn't see any they were in the Sakha bird books, I suspect they nested a little further north and away from the human hunting pressure.
Here's a couple of photo's and a video of the bird up on Ousefleet
and in a bit of light showing the braces.