Sea otters are just the most adorable. With their fur and their flippers and their swimming in the kelp forests, they're just like little stuffed animals. And to make them even cuter, they collect their favorite rocks.
Under each forearm, the sea otter has baggy folds of skin. The otters store food in these folds. They also store their favorite rocks. They use these rocks to break open mollusks and clams for food. Otters can crack open sea urchins and crabs with just their teeth.
The adult sea otter is the smallest marine mammal and it is an endangered species. Sea otters are also the only marine mammal that does not have a layer of blubber to keep it warm. Instead, their thick fur insulates them and keeps their body around 100 degrees.