I led a BBC outing to New Buffalo yesterday. For whatever reason it wasn't super heavily attended. That being said, there was a pretty sweet bird I noticed after about 30 minutes of standing there. A black and white long necked bird with a yellow bill appeared briefly in the bins, mostly staying hidden by not insubstantial waves. It's not that uncommon for a very distant Horned Grebe to stretch its neck and look pretty contrasty, but they don't have long yellow daggers for bills.
It took a few (anxiety provoking) minutes to re-find it, fortunately close enough to the New Buffalo breakwall that I could line up on some of the stones and wait for it to rise momentarily into view.
It worked its way a little closer and I had hopes it would stick around, but it kept mostly swimming south. Completely eliminating Clark's Grebe is tough, though Clark's should have a brighter yellower bill and would have less of the dark on top of the bill. This bird doesn't have a ton of black dipping below the eye though there is some, and it gets lost a little with the high contrast lighting conditions.