I was on a Lake Erie Island (Middle Bass Is.) this past weekend, not that far from the Canadian border and islands.

Parked in the "front yard" (lake) was a U.S. Border Patrol boat 20 feet off shore with a crew of 3-4.

I'm guessing that it was hiding out there waiting to interdict a boat(s) from Canada. Or perhaps they were waiting for a specific boat based on intelligence.

After being there for a couple of hours it raced off (4 outboard motors) around the East side of the Island headed North towards the nearby Canadian Island and out of sight.

Anyway, thought you might like to know that DHS does evidently patrol Lake Erie to some degree.