At the beginning of chapter 14 of Island of the Blue Dolphins, Karana must go get water from the spring. Due to her injured leg, this is a very difficult journey. Along the way, she encounters the wild dogs. Due to her injuries, Karana knows she is vulnerable. She initially scares them away by raising her bow and crawls on to get water. At the spring, the dogs surround her. It is here that Karana notes that the leader of the dog pack has yellow eyes.
Some low bushes grew there, and among them, with just his head showing, stood the big gray dog. He did not move, but his yellow eyes followed me, turning slowly as I drew near the cave.
The wild dogs surround Karana, and it seems that they have laid an ambush for her if she tries to escape. For safety, Karana moves into a nearby cave where she stays for six days.
At the beginning of chapter 15, Karana describes the leader of the dog pack again, emphasizing his yellow eyes.
I am sure that the pack grew bolder because of their leader, the big one with the thick fur around his neck and the yellow eyes.
This particular dog seems to be a newcomer to the island. Karana figures that he came with the Aleuts and was left behind during their quick getaway after the battle. This particular dog is different than the other dogs on the island which are smaller and have brown eyes. These differences make it clear to Karana that this large yellow-eyed dog is a newcomer.