text: A sea otter, resting on its back, holding its paw out of the water for warmth. While the sea otter has extremely dense fur on its body, the fur is less dense on its head, arms and paws so it will hold these out of the cold water to conserve body heat. Elkhorn Slough National Estuarine Research Reserve, Moss Landing, California, USA, Enhydra lutris, natural history stock photograph, photo id 21688