You’d think hitchhikers are more likely to be found on the highway to Whistler than in the ocean, but that’s the magical thing about the ocean, isn’t it? It’s full of surprises.
It turns out that there are all sorts of animals that hitchhike on other animals for a whole slew of reasons.
Take this crab, for example. It was observed peeking out from under the bell of a spotted jellyfish (Mastigias papua) by a keen-eyed Aquarium biologist behind the scenes. The spotted jellyfish itself could fit in the palm of your hand, so you can imagine how much smaller the crab is. The crab’s hind legs are shaped for swimming – they’re flat, like paddles.
This one appears to be a type of portunid crab (family Portunanidae, likely in the genus Carybdis). The family it belongs to is a huge group with over 400 described species. It was likely hiding under the bell of the jellyfish for protection.
Many different types (species) of animals seek shelter under jellyfish bells or among their tentacles. They include many species of crabs (local ones too), shrimp-like amphipods and fishes. Many of these animals form this type of association with jellyfishes at a certain life stage, usually when they’re young.
So the crab in this photo only hid under the jellyfish’s bell for a time. Once it grew a bit larger, the biologists found it on its own at the bottom of the exhibit – it became too big to fit under the jellyfish’s bell.
See these spotted jellyfish as part of the new exhibit Jelly Invasion, which starts on May 16.
Written by Karen Horak, writer-editor, content and digital experience at the Vancouver Aquarium