User blog comment:Lord Loss/Monster Hunter Theory... Blog/@comment-184.38.5.44-20121129223653

So I guess from MH4,it's safe to assume that the Kut Ku uses it's huge ears to hear for beetles and their larvae underground and than use their huge shovel like bottom beaks to dig them out.When they find the beetle,they grab it and than use their beaks to crush it into smaller pieces.

With the HC Blue Kut Ku's larger bottom jaw,I think it uses it for easier digging and to grab larger beetles.

Now Yian Garuga's beak,is most likely for crushing harder things like bone and the armor on some monsters skin but I think it could possibly eat the beetles if food was scarce.