An uninvited visitor at an aquarium almost wiped out the entire crab population. Find out how it snuck in

The aquarists at the Monterey Bay Aquarium noticed that less and less of their crabs in the Shale reef exhibit came out to eat during feeding times. Only once a red octopus, the size of a fist, crawled out of the shale reef onto the aquarium floor, did they realize why.

"We'd noticed that there weren't as many crabs coming out at feeding time in that exhibit. Now we realize that's where they'd all been going — into the octopus's tummy!" Exclaimed Barbara Utter, the senior aquarist.

The octopus managed to get entry to the aquarium on a rock or a sponge when it was still a baby. A baby red octopus is about the size of a fingernail, which explains why the little critter could hide out so successfully.

It spent it's time snacking away on the legitimate residents of the aquarium—the crabs. It was obviously living well, and managed to put on the bulk that made it's presence known to the aquarists.

Seeing that there is no 'undersea law' that can be enforced on the octopus for munching on the aquarium crabs, it is being prepped to live a life of captivity as a legitimate member of the aquarium's Splash Zone.

(Source)