Sea otters sleep on their backs, floating on top of the ocean like little furry rafts. To stop themselves drifting away from their friends, they hold paws - sometimes whole groups of otters link up into a long chain. A group of otters floating like this is called a “raft,” and the cutest sleepover on Earth.
Otters are also one of the few non-primate animals that use tools. When they find a clam or sea urchin, they grab a flat rock, lay back on the water like a dinner plate, and bash the shell open on their chest. They’re so attached to their favorite rocks that they actually carry them around in a loose pouch of skin tucked under each arm.
To survive the cold ocean without a layer of fat, sea otters have the thickest fur of any animal: up to a million hairs per square inch. That’s more hairs in one inch of otter than on most people’s entire head.
