Sea Otter and Her Pebbles

I've seen this otter a couple of times now in the past year or two. She plays with small pebbles, hitting them together, placing them on larger boulders, removing them, dropping them in the water, and diving to retrieve them. The folks at the Monterey Bay Aquarium say this otter was pup in their surrogate program in 2009. She's a full grown adult now, so she isn't mimicking tool use as pups might. Their best guess is she's just amusing herself. Who says otters don't know how to have fun!