Yeah, I see them on lots of walleyes from Sakakawea, DL, and every other small lake in the prairie pothole region. You just gotta look and you will eventually find them.
They don't bother me tho, at least not as much as the tapeworm looking things in the walleyes at DL, or the little black peppercorn looking parasites in the meat of perch on the east side of the state.