Regions with otters tend to host dense forests of kelp, a brown seaweed that anchors to the seafloor. Kelp forests provide a physical structure in which diverse marine communities find shelter and food. Sea otters prey on urchins, which consume kelp. According to James Estes, sea otter populations have dropped dramatically in Alaska and the Aleutian Islands. If sea otter populations in these areas continue to decline, what might happen with populations of sea urchins and kelp