"I'm not sure why it's come back," said Dudek, who posted his suspicions in a video on Facebook. "But someone is slicing and killing bass again. It's such a waste."

But the state Department of Natural Resources (DNR) doesn't believe that Green Lake's bass were intentionally killed this time around, as they were in the early 2000s by walleye fishermen upset over the prevalence of bass.

The fish may have been killed by something else, something that could be lurking in the live wells of the bass fishermen's own boats.