I visited my mother today. I know the back way from Gays Mills to Richland Center well. I slowed down at the Akan Village Garage because I saw the beaver dams there alive with activity. It appeared to be a major hatch.
This little stream is UN-named and empties in to Knapps Creek. The hatch was BWOs and the water was alive with them.
I casted once and caught this little brookie. I snapped a photo of her and inspected her gills for gill lice. They were loaded with gill lice. Her edges of her gills even looked tattered and darker colored due to the aggressive gill lice infestation.
I landed 9 more brookies in short order and all were loaded with gill lice. The light bulb went on at the 10th fish. The WDNR said that the gill lice usually doesn’t kill them by having them. Add stress on to the gill lice infestation and it could easily be fatal to the fish. Me catching them was that added stress they didn’t need. I might have killed all 10 of those brookies just by catching them.
Please check your brookies for gill lice when you catch them. If they are infected I would highly recommend not fishing that stretch.
I disinfected my gear with a 1% bleach solution and was sad as I drove away.
This is the first stream in Richland County I have discovered to have gill lice.
Better get the gates up and get a lawsuit started against your DNR too… 
On a serious note… how do they get it and is it native ? 
I have never heard of it, does it only afflict trout ? 