19 August 1998

Several species of jellyfish are found in North Carolina waters, carried here by oceans currents, wind and tides. Although jellyfish encounters may be unpleasant for beachgoers and swimmers, the world of these ocean travelers is quite fascinating. Jellyfish are unique in many ways. They have no hearts, no bones and no brains to speak of, yet they consist of a complex system or network of nerves that enable them to react to the world around them.   Their looks are deceiving, too. Although it appears otherwise, jellyfish are not made of jelly at all. Their jelly-like appearance comes from their protective skins that are filled with a substance that is approximately 95 percent water. Muscle fibers laced through the jellyfish’s body hold it together.   During the summer months, its common to see moon jellies, sea nettles, cabbage head and mushroom jellyfish off North Carolina beaches. Later in the fall, the Lion’s Mane jelly and the Portuguese man-of-war the can be found along our coast.

It’s easy to see how the moon jellyfish, Aurelia aurita, got it’s name. Moon jellies are common in North Carolina waters during the summer and fall. Photo by Paul Humann

The moon jellyfish, Aurelia aurita, is named for its moon-like shape and translucent white color. This jellyfish is found in our waters from April to early November, depending on water temperature and ocean currents. It is most common in late summer and early fall.

A moon jellyfish’s tentacles are short and are located on the edges of its disked-shaped body. Four frilly oral arms hang down from underneath its body, or umbrella. These arms will be distinctly pink during August or September because of the large number of larvae developing on the edge of its umbrella. If you look at a moon jelly from above, you’ll see four purple horseshoe shapes, which are portions of its reproductive system.

The sea nettle, Chrysaora quinquecirrha, is about the same size as a moon jelly, however its umbrella may be pale white and may look like the spokes of a wheel. It is also commonly found along the North Carolina coast during the summer months. It is distinct from the moon jelly in that its oral arms are longer and it has fewer yet longer tentacles.

The mushroom jellyfish, Rhopilema verrilli, often floats off our coast between July and November, and it may even enter sounds and estuaries. It is another jelly named for its shape and it can grow quite large -- up to 14 inches in diameter. Because of its size, it can easily break if lifted out of the water. It has no tentacles on its umbrella; instead its oral arms are subdivided and almost fingerlike, extending down from the center of its umbrella. The mushroom jelly feeds on tiny plankton that are swept into its mouth by the beating of hairlike cilia on its arms.

The jellybomb or cabbage head jellyfish, Stomolophus meleagris, is whitish or opaque with a brown ring around the edge of its umbrella. Common in North Carolina waters from May to November, it also may enter sounds where the water is almost as salty as the ocean. Like the mushroom jelly, the cabbage head has no tentacles. Its oral arms extend down just below the edge of its umbrella.

The Lion’s Mane, Cyanea capillata, is the world’s largest jelly, measuring up to eight feet in width with tentacles more than 100 feet long. This mass of tentacles gives this jelly its name, since it resembles the thick mane of a male lion. It ranges in color from fuschia to purple with creamy to pinkish-white tentacles. It is common in our waters, including our sounds, from October to May.

Most of these jellies rely on their tentacles for capturing food. Tentacles are covered with microscopic, stinging cells called nematocysts which paralyze plankton, shrimp or small fish. The oral arms then carry the food to the jellyfish’s mouth.

The Portuguese man-of-war, Physalia physalis, is not a true jelly, since it is a colony of specialized polyps that live as one organism. The Portuguese man-of-war is distinguished by its float which acts as a sail, pushing the the colony along as it travels through the ocean. Strong east or southeast winds can blow this sailor inshore during the summer or early fall; occasional winter or spring storms may also bring the Portuguese man-of-war ashore. The stinging tentacles that stretch out beneath the float can produce a painful sting even after the animal is dead or after they have become detached from the animal. This is true for the tentacles of true jellyfish as well.

Sometimes, the tentacles catch a beachcomber’s foot or the arms or legs of a swimmer who happens to be sharing the water with a jellyfish. A nematocyst contains a barb on the end of a coiled string and it can act like a harpoon, sending painful stings into whatever it comes in contact with.

Stings from some jellyfish may require a doctor’s care. Everyone’s level of sensitivity to jellyfish toxin is different. People with a history of allergies to bee stings should be especially careful if stung by a jelly.

Basic first aid for stings should include:

• Carefully removing any remaining tentacles; do not rub the area with sand since rough treatment could result in additional stings.

• Washing the injured area with diluted ammonia or vinegar.

• If symptoms are severe, such as respiratory distress, muscle cramps or dizziness, seek medical attention immediately.