A great example of the superstitious nature of Karana's people happens in the first chapter of Island of the Blue Dolphins by Scott O'Dell. Karana's father is the chief of their tribe, and he is the one who greets a small contingency of men from the Russian ship who have come from to the island to hunt for otter.

Captain Orlov has come with forty men to hunt, and he parleys with the chief for permission. Karana's father thrusts his spear into the ground and announces himself as Chief Chowig, chief of the Ghalas-at tribe. Karana is on the cliff, and she is surprised that her father has so quickly revealed his secret name to these strangers. 

I was surprised that he gave his real name to a stranger. Everyone in our tribe had two names, the real one which was secret and was seldom used, and one which was common, for if people use your secret name it becomes worn out and loses its magic.

The girl's name is Won-a-pa-lei, or, "The Girl with the Long Black Hair." Her secret name is Karana, and she does not reveal it to many.

When the Russians leave, they kill Karana's father, and Karana superstitiously believes this happens because he revealed his secret name to the hunters.