Yes. Pike will also sometimes eat their own if they are very hungry and haven't eaten in a while, but this isn't common in the wild. This is because most things in the water are too big for a Pike to catch on its teeth. But smaller fish like minnows are easy prey. The pike is not crazy about hunting for food though, so it just waits around until someone fishes out some small fish or when something kills one of the nearby and they can pick at it before anything else comes by and feeds on it instead of him eating it all himself.