Hello, I just found out that N. Mockingbirds are not that common around Duluth and was asked to mention where I saw it. It was along the nature trail right before the little boardwalk to the left that comes off the end of the paved part of the trail (heading south). At least I think that's where it was. I was busy watching a bunch of warblers in some bushes along the dunes and happened to see it fly out and onto the airport fence. It then flew back across the path in front of me and into the bushes.
Interstingly, Mockingbirds used to be a rare find in Syracuse until about 5 years ago. Now they are a regular find. Molly Thompson Duluth, MN