It's not uncommon to find Herring Gulls feeding on dead fish along the Illinois, Lake Michigan lakefront, especially in the Fall season. Below is a series of photos taken at 63rd Street Beach on 01 Ocotober 2014.
When I arrived at the beach this adult was feeding:
The 1st cycle has almost completely replaced all of its juvenile scapulars which is just a tad more advanced than what I've been seeing for the last couple of weeks in Michigan City and New Buffalo, but still, completely expected for this region.
The relatively large pale tips to the newly grown primaries on the 2nd cycle bird are the boldest they'll appear all season. Here's a better look at the open wing:
The white tips will soon start to wear down as the season progresses and will likely be unnoticeable by the end of winter.