Size1-3 feet (0.30–0.91 m)
DietVariety of zooplankton including tiny crustaceans, invertebrate larvae, comb jellies, small fishes, fish eggs and larvae, as well as other jellies
RangeCoastal waters of California and Oregon, less common north to the Gulf of Alaska, west to Japan and south to the Baja Peninsula
- Dome-shaped body that may measure 1-3 feet (0.30–0.91 m) in diameter.
- The dome, or “bell,” is golden brown in color and has four ruffled oral arms extending downward as much as 12 feet (3.6 m) from its underside.
- There are also about 24 to 40 thin, maroon tentacles extending downward from around the perimeter of the bell.
- This bell-and-tentacles body shape is the adult stage of the nettle, called a “medusa.”
This bell-and-tentacles body shape is the adult stage of the nettle, called a “medusa.”
- Diet consists of a wide variety of zooplankton including tiny crustaceans, invertebrate larvae, comb jellies, small fishes, fish eggs and larvae, as well as other jellies.
- Occurs in the coastal waters of California and Oregon, less common north to the Gulf of Alaska, west to Japan and south to the Baja Peninsula.
- Found in largest numbers during fall and winter.
- In the familiar medusa stage, the male and female sea nettle sexes are separate and release sperm and eggs into the water daily during spawning periods. This is the sexual reproductive phase.
- Fertilized eggs develop into larvae that drift and then settle to the bottom, attaching to hard surfaces, such as oyster shells.
- Larvae develop into small polyps that remain on the bottom in a dormant state throughout winter. During the spring and summer, the polyps “bud off” tiny sea nettles (called ephryae) about a quarter of an inch in diameter that grow rapidly into a conspicuous medusa. This is the asexual reproductive phase.
- Sea nettles are made up mostly of water containing salts, with organic materials only totaling about 6.4 ounces (181 g) of its entire weight.
- “Not Evaluated” on the IUCN Red List.
- Contact with the tentacles of this sea nettle can result in a painful sting. Some stings could be severe enough to require hospitalization.
- In some areas, the Pacific sea nettle population may become so large that jellies clog the nets of fishermen and block water intakes. These conditions can last for months.
- Some scientists believe human influences in coastal areas are creating conditions more favorable to jellies, leading to the increased frequency of large blooms.
- High concentrations of jellies are thought to reduce populations of larval fishes, resulting in lower commercial catches of adult fish.
- Natural predators include sea turtles, some sea birds and some fish species (such as the mola mola).
- The name Chrysaora has its origins in Greek mythology. Chrysaora was the son of Poseidon and Medusa and translates into “golden falchion” (a commonly used curved sword which could cut through armor), a reference to the stinging ability of these jellies.
- Also known as the brown sea nettle.
- A group of jellies is called a smack.