I think it's worth noting, given a recent proliferation of female Barrow's Goldeneye reports from the upper CT River, that a yellow bill is not a diagnostic feature. As is generally true with most IDs, it's never wise to base them on a single feature. Female Barrow's Goldeneyes usually have yellow bills, but not always. Female Common Goldeneyes usually have primarily black bills, but not always. Some can be very yellow. A good, solid ID of a female Barrow's should be based on bill size and shape and head shape (in addition to color). The bills are typically short and deep compared to Common. The head shape is also different and well illustrated in good field guides (what? you don't use a field guide? I'm startled by how often that seems to be true these days). At any rate, a decent amount of recent female reports seem to suggest that observers started and stopped at bill color. Some good current CT photos (not easy to get) of female Barrow's would be great to have. Greg Hanisek Waterbury