North American River Otter
Besides their eye sight underwater, river otters use their whiskers to help hunt for food. The otter’s whiskers can sense vibrations of fish movement, so they are able to detect the proximity of their prey. Otters are also known to have very high and speedy metabolism. Within an hour of eating, the substance of their meal makes it through their digestive tracts. In the winter to help river otters stay warm, they have 57,800 hairs per square centimeter that make up their thick, warm coat.