As sea ice disappears because of climate change so may polar bears. Some ecologists believe polar bears could be extinct by the end of the century.

On this week's Sprouts we hear polar bears feasting on the remains of bowhead whales on the edge of the Beaufort Sea while cultural anthropologist Richard Nelson, who is standing nearby, describes the scene. He describes their actions and behavior and then goes on to explain the lives of polar bears, humans' historical relationship to them, environmental policy that affects them, and their chances for survival.

This week's Sprouts edition is produced by Lisa Busch and Richard Nelson of "Encounters," at KCAW in Sitka, Alaska. Richard Nelson is an acclaimed Alaskan cultural anthropologist and award winning nature writer. He hosts "Encounters," an environmental program produced at KCAW in Sitka, Alaska that brings the sounds of the northern wild to the radio. For more information about Encounters, visit EncountersNorth.org. Encounters is funded by the National Science Foundation.