How does Jack's description of being hunted connect to the fears of the little ones ?

I don't think that Jack ever "fears" the Lillluns. If anything they become an extension of pigs for his obsession to hunt and kill. The chapter's beginning follows Jack on a solitary hunt through the forest, which underscores Jack's importance to the novel and explains his preoccupation with hunting. For Jack, hunting is not an instinctive talent but a skill that he continues to develop as the story unfolds. His motives for hunting are disturbing. He hunts not for the ostensible purpose of gaining food to eat but for his personal enjoyment. Golding indicates that there is something tremendously dangerous in Jack's obsession; his expression is one of "madness" when he speaks about his desire to kill. At this point in the story Jack is not sufficiently prepared to kill, but he is approaching the point at which he can inflict mortal violence upon another, whether a pig or a person.