Around 8:35 p.m., Barbara and I were setting up lawn chairs in the parking lot of the Riverfront Museum Center to count the Chimney Swifts that are roosting in the chimney of the old National Guard Armory. The museum center and armory are on Main Street on the west bank of the Rock River just north of downtown Rockford. We spotted a few gulls flying by going upriver (north), which I initially presumed were the Herring Gulls that have been hanging around Rockford between the airport quarry pond and the Rock River almost all of the summer. When we looked at the gulls with our binoculars two of them were Herring Gulls, but one individual was smaller, had a black head, a dark mantle, black primaries, no white between the black primary tips and the mantle, and no white outer primaries. It disappeared from sight behind the Museum Center building.
There is a log jam at the confluence of Spring Creek and the Rock River, about 1 block north of the Auburn Street bridge, where the Herring Gulls have been roosting in the evening, so we headed up there. This location is one block north of Auburn Street along the Rock River. The log jam is best viewed from upper Harlem Blvd. on the west bank of the river. Upon arrival, Barbara immediately spotted the Laughing Gull swimming in the river among the log jam. We didn’t have a scope, and the light was fading fast, but were able to call another birder who lives in the neighborhood (he was at the Armory about to count swifts, too!) so he drove up with his scope. I suspect that the gull will spend the night there and may still be present very early tomorrow morning.
We headed back to the armory and watched hundreds of swifts fly into the chimney until about 9:10 or so.