I took the time to look it up and the spot does actually fade when the fish get's older. I imagin that it takes a very long time for the fish to reach a size where it would not become food anymore. There are several fish that would feed on a bowfin. Large catfish (channel, blue, flathead, bullhead etc), pike and muskellunge, black basses, walleye, large trout (lake trout). Then you also have snakes, turtles, birds, otters among others.
prob a stupid ? but i feel like learning what ocellaris im lost thanks