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Japanese spider crabs

Did you know?

Macrocheira kaempferi

It’s not a spider – but it looks a bit like one! With a leg span up to 12 feet, this is the biggest crab species in the world.

Meet our giant crabs

Living deep down
in the Pacific.
Japanese spider crabs live in the deep, cold depths of the Pacific ocean around Japan. Our crabs share a habitat inside the Pacific Seas Aquarium, just near the entrance.
Living deep
and eating off the floor
Imagine the Seattle Space Needle, pointing 600 feet under the ocean…that’s how deep these crabs like to live!
They scavenge the sandy sea floor for dead plants and animals – with a live treat whenever they can catch it.
From legless larvae
to long-legged giants
Female spiders crabs carry fertilized eggs on a part of their abdomens until they hatch into tiny planktonic larvae.
These look nothing like adult crabs! Instead, they are small, round, legless and transparent, and drift in the ocean.
Crab camouflage
Cover your carapace
Some young crabs “decorate” their carapaces with small anemones or algae as camouflage.
But adults rarely do – they’re too big to have to hide from predators!

Protect the Ocean

It takes all of us.

THE THREAT: Ocean animals are in danger – from humans. Our plastic and oil spills engulf them. Our boats and nets overfish them. And our carbon dioxide warms their world.

TAKE ACTION: Stop using straws, bottles and other single-use plastic. Drive less, recycle more. Pick up pet poop and avoid pesticides. Eat sustainable seafood. And speak up. Together we can protect the ocean.

Aquarium Stories

Behind the Shimmer

It’s more than just a play of light. Wander down the ramps of the new Pacific Seas Aquarium, and you’ll pass through shimmers of colored light. You’re immersed in their play and flicker, as if swimming through a sunlit lagoon. It’s art – the light installation “Shimmer,” by California artist Gordon Huether – but the … Continued

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Lunchtime in the aquarium

Animal care aide Jordan Jirik lies flat on her stomach, her head hanging over the top of Baja Bay’s 280,000-gallon habitat. Below her, five hungry spotted eagle rays swim eagerly up to a large black sign with a big white X emblazoned on it. It’s their feeding-station target. And when it appears in the water, … Continued

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We opened the Pacific Seas Aquarium!

Two dozen necks crane up, up, up, eyes riveted on the scene above, as four hammerhead sharks cruise overhead. Sunny the sea turtle joins the scene, swimming unhurriedly by and then diving deeper into his home. Suddenly, two eagle rays “fly” overhead, their pectoral fins gently flapping up and down to propel them through the … Continued

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Who's Nearby?
Love our spider crabs? Then look for our jellies, just down the “shimmer” ramp!