Northern Sea Nettle

(Chrysaora melanaster)

  • Animal Type


  • Exhibits

    Not currently on exhibit.

  • Range

    Pacific Ocean


This jelly's bell can be white to dark purple or red, with dark lines radiating from the top of the bell. The species derives its name from the Greek words melas and aster, which translates to "black star" because of the pattern on its bell.

Although not very venomous, their sting can cause an allergic reaction in some people. Their stinging cells, which are called nematocysts, are powerful, capable of causing serious skin irritation and burning sensations.

A Note from the Caretaker

It has been reported that the ancient ninja warriors of Japan used to scatter dried venom from this species into the wind to irritate the nose and eyes of their enemies during battle.

Quick Facts

Learn more about the northern sea nettle! Did you know that this jelly's tentacles can grow to a length of 10 feet?

This sea nettle can be found in the Pacific Ocean from Japan north to the Bering Sea.

They feed on zooplankton, including small crustaceans and other jellies.

The bell of this species can measure up to 12 inches wide. Tentacles on giant specimens can reach as long as 10 feet.

In the past, jelly populations were kept in check by predators like sea turtles and jelly-eating fish. Due to the reduction of their 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% water and an adult leatherback can weigh more than 2,000 pounds, one turtle can consume a lot of jellies.

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