User blog comment:Kogath/Monster Hunter Frontier G5 Discussion/@comment-6050823-20140813105402/@comment-4009941-20140817182501

In multiple games you can spy on Kusha eating ore like in the Jungle. This is likely a example of a kusha on a special diet like gold desposits or drinking from water with lots of Gold in it(Lots of MH world is unexplored so there should be tons of locations where humans have not collected the gold and going by the way gold is in MH I would assume its more common than in our world).