Poor Osbourne, but that was pretty noble of him. Wally knows he eats fish, but it might have crushed him to find that he was using Wally’s method of catching the ones needing saving just to eat them.
Are fish really trapped like that in little puddles? I don’t know, that was just for the comic. I suppose it’s possible with the shifting of the ice that it could happen. The actual puddles however, do exist out on the ice. In many cases though, they are not just small puddles as they appear, but are actually small openings to huge underwater caverns under the ice. Keep that in mind next time you’re in Antarctica and you’re wanting to go jump in one to splash a friend.