Night Wings by Joseph Bruchac

"Suddenly something drops down with a whomp of wings that blot out the stars.  Two red eyes stare at me from the inhuman face of the one who guards this place."  It was only a dream, but it was a dream so powerful that Paul could not shake it from his memory.  He knew the story of Pmola, a winged creature who hid a treasure on the mountain, and his ancestor, the brave hunter,  whose live was spared by Pmola.  While Paul had great respect for his elders, he surely had a hard time believing such a story and such a creature was real.  But when modern treasure hunters kidnap him and his grandfather and force them to lead the way to Pmola's hidden treasure, Paul begins to believe that only the wisdom and the spirits of the ancients can save them.