On Friday I felt like checking the river for ducks and gulls, so I went to Strathcona Park at lunch. I wasn’t surprised to see all the Ring-billed Gulls there – they are back in droves, and I counted over 70 of them in the water and standing on the ice at the margins of the river. I was hoping to see some other species, though, particularly the much larger Great Black-backed and Glaucous Gulls that sometimes can be found loafing along the Rideau River; however, the only other species I saw was a Herring Gull examining a dead fish on the ice in the middle of the river.
About ten Canada Geese were back as well, while at least 20 Common Goldeneyes were still present in the open area north of the new bridge. As I was scanning them, I noticed one of the female ducks had a bright orange bill – so bright it was noticeable even without binoculars.
I had heard there was a female Barrow’s Goldeneye at Strathcona Park, but I didn’t really expect to see it. The most useful field mark in separating a potential female Barrow’s Goldeneye from the more abundant Common Goldeneye in winter is the bill colour – Barrow’s Goldeneyes have a bright pumpkin-orange bill, while most Common Goldeneyes have a black bill with a variable yellow tip. However, the bill colour alone is not diagnostic, as some female Common Goldeneyes can show a mostly yellowish-orange bill as well. Still, it is an important clue that you might have something different, and a signal that you should carefully examine a few other field marks before making a positive ID.
The most important field marks in distinguishing the two female goldeneyes are the shape of the head and bill. The female Barrow’s Goldeneye has an oval or elliptical-shaped head, whereas the female Common Goldeneye has a more triangular-shaped head with a noticeable peak. In the photos above you can see how the Barrow’s Goldeneye has a steep forehead and a flat crown. She also has long, puffy feathers on the back of her neck reminiscent of the crest of a female Hooded Merganser. In comparison, the Common Goldeneye has a sleek head and sloping forehead; these differences in profile remind me of the differences between a Canada Goose and a Cackling Goose.
As with scaup, the head shape changes depending on whether the bird is relaxed or actively diving. In these two images, the head of the Barrow’s Goldeneye appears sleeker as I had just caught her emerging from a dive. Unfortunately for my photographs, she was a very mobile bird, diving frequently while actively swimming down the river, and I never did know just where she was going to pop up next!
Bill shape is the other field mark that separates the two goldeneye species, and closer views are needed to see this. The bill of the Barrow’s Goldeneye is slightly shorter and stubbier than the bill of the Common Goldeneye, which further accentuates the steep forehead. In contrast, the Common Goldeneye has a longer, flatter bill; this is best seen in the first photo above.
I was thrilled to finally see and identify my first female Barrow’s Goldeneye, and I wished I could have spent more time watching her – I would have loved to have caught her in the same frame as a female Common Goldeneye for comparison. Perhaps another time, although with the temperatures rising and river opening up, our winter goldeneyes won’t be here for much longer.