PS - I don't know how many of them die from the impact, but wow - that has got to hurt. Probably going at maximum velocity when they hit, which isat least 15 -20 mph for a large fish.

And I don't know if a big pole would work or not, but breaking up the ice with a boat definately does. If you are traveling along through a frozen stream, instead of coming up on a bunch of ice, you won't see the fish hitting the ice because you make so much noise getting there that the fish are allgone by the time you get there. But you can see the blood in the water from where they started jumping when they first heard you.