Warm ocean currents off the coast of Southern California delivered a surprise to a couple of squid fishermen this past weekend.
A female argonaut ― an octopus also called a paper nautilus ― turned up in their bait box, The Daily Breeze reported Oct. 16. The men recognized the rare find and turned it over to the Cabrillo Marine Aquarium, said Kiersten Darrow, the aquarium's research curator.
Argonauts live near the surface of the open ocean, unlike most other octopuses, which live near the bottom. The argonauts secrete thin, translucent shells that hold pockets of air, helping them float. Their normal range is the warm water along the equator, especially near Indonesia and the Philippines, Darrow told OurAmazingPlanet.
"I've never seen anything quite like this," she said of the California find.
The silvery, baseball-size animal the fishermen caught has eight tentacles, big eyes and the color-changing abilities characteristic of an octopus. Its size means it's probably a full-grown adult, Darrow said.
In one of the aquarium's Jacuzzi-sized tanks, the octopus is now exploring its surroundings, flashing gold when it sees an overhead light or purple when it's in darker water, Darrow said.
"A couple of times, it's reached out its tentacles and explored around the tank, touching the different walls, especially if we have food sitting on the bottom of the tank. It seems like it's smelling the water," she said.
When the argonaut first arrived at the aquarium, it lay at the bottom of its tank without moving. Aquarium staff gently nudged it to surface so it could suck in some air. "Sure enough, it was able to float in water after that," Darrow said.
The octopus is on a diet of shrimp and fish. The aquarium staff hopes to see it exhibit hunting behaviors. If it does, they'll prepare to release the argonaut back into the wild.
"Our first goal was to try to make it better," Darrow said. "We'd like to release it, but we don't want to release it if it's sinking to the bottom. If the animal can hunt food, then we know it has good chance of survival."
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