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Moon Jellyfish

Moon Jelly

Aurelia aurita

Moon Jellyfish Moon Jellyfish Moon Jellyfish Moon Jellyfish Moon Jellyfish

The moon jelly has translucent white, saucer-shaped bell, with a blue-gray transparent disk at its center through which the horseshoe-shaped gonads are visible. Short, delicate, fringe-like tentacles hang from the bell margins.

When deprived of food, they can shrink to one tenth of their original size to save energy. They redevelop to normal size when food is available.

Did You Know?

When deprived of food, they can shrink to one-tenth of their size to save energy.




Bell can be up to 12 inches wide, about the size of a dinner plate.


Temperate and tropical oceans worldwide; near the surface of shallow bays and harbors

Population Status

In the past, jelly populations were kept in check by predators like sea turtles and jelly-eating fish. Due to the reduction of these predators, jelly populations are growing at alarming rates.


Sea turtles and other jelly-eating animals such as tuna, sunfish, butterfish and spiny dogfish keep the jelly populations in balance. All seven species of sea turtles include them in their diets. The largest sea turtle species, the leatherback, depends on jellies for food. Because jellies are more than 90 percent water and an adult leatherback can weigh more than 2,000 pounds, one turtle can consume a lot of jellies.

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