I wasn’t able to count all the swans I found yesterday at Blakes Lake in the Green Island Wetlands. I think it’s safe to say there were at least 400, but probably more, feeding in the shallow waters of the lake. Heat shimmer above the water surface made it kinda difficult to see details of the birds in the viewfinder of the camera. While standing on the dyke there were quite a few more swans moving in and this was the chance to make a few clicks from a shorter distance. It wasn’t until I had a closer look at the birds on the screen of my computer that I realized that there were quite a few Tundra Swans among the Trumpeter Swans, which latter I had seen during the last few weeks already. This also explained the considerable increase in numbers of swans present on the lake.
While the Trumpeter Swans may stay here in eastern Iowa during the winter, the Tundra Swans spent the winter at the Mid-Atlantic coast. They are back now and on the way to their breeding grounds in the arctic region of Canada and Alaska. Trumpeter Swans are slightly bigger but this is not always a safe indicator for identification. It is the yellow spot that adult Tundra Swans show at the base of their bill that leaves no doubt about what species we see.
The yellow spot is at least very good visible in the full size photo of these two Tundra Swans flying overhead. The size reduced picture you see here in the blog makes it a little more difficult to see this important feature.