Karana was stranded alone on an island off the coast of California. She had to learn to survive in the wilderness without tools or other people. Some of the challenges she faced were finding food, building shelter, and keeping wild animals from stealing her stored supplies. To protect her food, she built a fence using strong seal sinew instead of kelp, since animals would gnaw through kelp. The passage discusses Karana's struggles and resourcefulness in overcoming challenges to survive alone in the wilderness.