Moon jelly
Aurelia labiata
- On view
- Open Sea
- Animal type
- Invertebrates
- Ecosystem
- Open ocean
- Relatives
- Sea nettles; Class: Scyphozoa
- Diet
- Zooplankton
- Range
- North East Pacific; common in Monterey Bay and along the California coast
- Size
- Up to 24 inches (60 cm) in diameter
Meet the moon jelly
This dreamy jelly is named for their translucent, moon-like bell. Instead of long trailing tentacles, the moon jelly has short tentacles that sweep food toward the mucous layer on the edge of the bell.
Natural history
Scientists have studied the life cycle of this jelly extensively. Adult male moon jellies release strands of sperm, which are ingested by females. After fertilization, females brood their larvae on their oral arms. The larvae will release and settle on or near the seafloor and grow into polyps. In the asexual phase, polyps can create buds that grow into new polyps. They will also undergo metamorphosis in this phase known as strobilation, where they produce tens of ephyrae, which release and grow into adult medusae.
Related videos
The moon jelly lifecycle
These extraordinary lunar beauties go through many phases in their lives—from egg to polyp to medusa with a few steps in between.
Conservation
Though moon jelly populations are still plentiful, plastic bags that end up in the ocean look just like these jellies to animals that depend on them as a food source. Thousands of turtles and birds die each year after swallowing indigestible wads of plastic they mistake for jellies.
You can help by eliminating single-use plastics from your daily life. Bring your own reusable grocery bag next time you go shopping to help keep plastic bags out of the ocean.
Cool facts
- Although they didn't get to the moon, nearly 2,500 moon jelly polyps and ephyrae—two early stages in the jelly life cycle—went into orbit aboard the space shuttle Columbia in May 1991. They were part of a study on the effects of weightlessness on the development of internal organs in juvenile jellies.
Related videos
Moon jellies up close
Jellies have two kinds of skin tissues: an outer exchange layer and an inner stomach skin. The frilly parts in the center are called oral arms, which are projections of the stomach made of gastrodermis. They digest food from a distance! Yum.
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