Is it a Fish? A Snake? A Jelly? Actually, it’s a Mimic Octopus—and We Have One on Exhibit in Tentacles!

Ever wish you could become someone else? The mimic octopus can. In less time than it takes to say “alter ego,” this curious cephalopod can become a venomous lion fish. Or a sea snake. Or a jelly.

“It will mimic these other animals when it’s threatened,” says Aquarist Chris Payne. “To become a snake, for instance, it will display black-and-white bands, extend two arms lengthwise and bury the other arms in the sand.”

In another favorite trick, it outspreads all its tentacles like a big prickly ball, to resemble the spines on a lion fish. Or it expands its mantle to look like a giant jelly. It all says one thing to a potential predator: Stay clear!

We’re one of the few aquariums to display this fascinating species (Thaumoctopus mimicus), which was only discovered in 1998, says Chris. Ours came from Japan, and is almost two feet from tip to tip. Its native habitat is sandy estuaries in the Indo-Pacific region.

Come find it if you can!


Learn more about our Tentacles exhibit

Watch the mimic octopus become four different animals


Curious about some of the science behind our Tentacles exhibit? Peek inside the world of deep-sea research at the Monterey Bay Aquarium Research Institute’s Open House July 19! Learn more

Curious about some of the science behind our Tentacles exhibit? Peek inside the world of deep-sea research at the Monterey Bay Aquarium Research Institute’s Open House July 19!

Learn more

Join us a for a special member night: Picnic by the Bay July 10! Bring your own picnic  and enjoy dining on our ocean-front decks or inside the Aquarium in front of your favorite exhibit. Not a member? Join now! Learn more 

Join us a for a special member night: Picnic by the Bay July 10! Bring your own picnic  and enjoy dining on our ocean-front decks or inside the Aquarium in front of your favorite exhibit. Not a member? Join now!

Learn more 


Our aquarists can get pretty wrapped up in their work! Share YOUR love of cephalopods on Instagram or Twitter and you could win one of eight packs of eight tickets to the Aquarium! #MBATentaclesLearn more 

Our aquarists can get pretty wrapped up in their work! Share YOUR love of cephalopods on Instagram or Twitter and you could win one of eight packs of eight tickets to the Aquarium! #MBATentacles

Learn more 


Nature’s Fireworks: We Discover the Flower Hat Jelly Life Cycle

Some things are worth waiting for – even if it takes 12 years.

Our jelly biologists have discovered the elusive life cycle of Olindias formosus – the stunning flower hat jelly, whose multicolored, fluorescent-tipped tentacles are like a living fireworks show.

The flower hat jelly was first discovered in waters off Japan over 100 years ago, but its life cycle was a mystery. Biologists around the world have been eager to exhibit this gorgeous jelly, but were unable to culture it to adulthood. Now, after 12 years of research, we solved the mystery, and you can see them in The Jellies Experience special exhibition.

“We’re thrilled to discover the life cycle of the flower hat jelly,” said Senior Aquarist Wyatt Patry. “Our team succeeded through collaboration, diligence and a bit of good luck.”

Our discovery could lead to predicting dangerous jelly “blooms” in the wild. The flower hat jelly packs a powerful sting, enabling it to kill and eat fish – and harm humans. Blooms of hundreds or thousands of these jellies off Japan and Brazil have resulted in injuries to many beachgoers, and at least one death, Patry said.

About the Flower Hat Jelly

Found in coastal waters off southern Japan, Brazil and Argentina, and in the Mediterranean, the flower hat jelly has brilliant tentacles trailing from its translucent, pinstriped bell. Another set of curly tentacles under its bell can quickly unfurl and grab prey. This nocturnal species swims in the water column at night and attaches itself to the seafloor during the day.

Our work to understand the life cycle of this mysterious jelly began in 2002 during the Jellies: Living Art special exhibition, which ran from 2002 to 2008. That team was the first to successfully exhibit flower hat jellies in the United States, and culture fertilized eggs and larvae – another first.

Shining a Light on an Amazing Life Cycle

Patry said the current team’s initial breakthrough occurred with a redesigned exhibit that let flower hat jellies capture and eat live fish and kept them away from debris on the bottom. Patry said the team hoped those conditions would encourage successful reproduction – and they did.

Special blue lighting in the exhibit was the next breakthrough. The flower hat jellies, which are fluorescent, are in a gallery that interprets three different types of “lights” in certain jellies – fluorescence, bioluminescence and diffraction. About six months after putting a batch of flower hat jellies on exhibit, Patry noticed two previously unseen stages of their life cycle – polyps and tiny baby jellies.

“I was only able to see them because they are fluorescent, like the adults,” Patry said. “From there we worked with the polyps to refine the ideal food and temperature requirements for them to produce more babies.”

Still have your first ticket to the Aquarium? We do! This week’s #ThrowbackThursday features our first-ever printed tickets, including one to our Grand Opening in 1984. We’re celebrating 30 years—help us reach our future goals

Still have your first ticket to the Aquarium? We do! This week’s #ThrowbackThursday features our first-ever printed tickets, including one to our Grand Opening in 1984.

We’re celebrating 30 years—help us reach our future goals

Music and molas? Evenings by the Bay starts this weekend! We’re open until 8 p.m. on Saturdays and Sundays so you can see the Aquarium in a whole new light. Learn more

Music and molas? Evenings by the Bay starts this weekend! We’re open until 8 p.m. on Saturdays and Sundays so you can see the Aquarium in a whole new light. 

Learn more

Remember hearing about Juno, the rescued pup that was reared behind the scenes by our exhibit otter, Ivy? Looks like she’s thriving at her new home at the Oregon Zoo!

Learn how we’re helping save sea otters

(Shervin Hess/Oregon Zoo)

Will fish and other #ocean animals get left high and dry? Learn more in our latest podcast.  

Where do you find inspiration? First as a volunteer and now as an assistant aquarist, Michelle Stamme loves working with our eight-armed animals—and painting them!

Share your love of #MBATentacles and you could win!

About me

The Monterey Bay Aquarium, perched on the edge of a world-famous coastline, is your window to the wonders of the ocean. It’s located on historic Cannery Row in Monterey and is open daily except Christmas Day.

For more information about our animals and exhibits, and to view our live web cams, please visit www.montereybayaquarium.org.

Hours of operation vary by season. Daily schedules and tickets are available on our website or by calling
(831) 648-4800.