Rising gracefully toward the ocean’s surface, the umbrella-shaped creature with short, near transparent tentacles, resembles a spaceship from another galaxy. Easily identified by the four small, whitish to pinkish, horseshoe-shaped structures near the center of its bell, the attractive moon jellyfish is a favorite exhibit at many of our public aquariums. Though moon jellyfish can tolerate sea temperatures of 210 F to 870 F, they tend to inhabit mainly warmer coastal and open waters of the Atlantic, Pacific and Indian Oceans. In Rhode Island, they are more common in late summer whereas in Long Island Sound, they tend usually make their first appearance in late spring. They are the most common jellyfish found in New Jersey waters. Luckily, contact with their stinging cells generally produces only a mild burning or prickly sensation.
These sea animals have occupied the seas some 650 million years, long before the age of dinosaurs. It has been estimated that more than 1.3 million different species now populate the world’s oceans. In 2016, NOAA, surveying the Mariana Trench, discovered a new species of jellyfish living at a depth of 2.3 miles below the surface! Three years later, another creature, suspected to be a jellyfish, was encountered at the bottom of the Indian Ocean’s Java Trench.
Jellyfish are up to 98 percent water. They have no bones, brain, heart or blood. Their digestive system consists of a single opening that serves both as a mouth and anus. Viewed from a safe distance, these beautiful gelatinous animals propel themselves in the water by pulsating their bell, while also hitching a ride on the ocean currents. In Japan, Korea and China, these slightly salty and chewy critters are sought out as a delicacy. Some are actually made into a candy. An estimated 25 to 30 species of jellyfish are said to be edible.
One of the largest of these sea creatures, common to our coastal waters, is the Lion’s Mane jellyfish. Locally, the diameter of its reddish to pinkish-yellow bell varies between 6 to 12 inches. Its tentacles can reach a length of 1.5 feet. But in Arctic waters, the creature can grow a bell of 8 feet in diameter with 100+ feet tentacles! In Sir Arthur Conan Doyle’s tale “The Adventure of the Lion's Mane,”
vacationing Sherlock Holmes eventually identifies the killer of a man found dead on the beach as the Lion’s Mane jellyfish. In reality, the species is considered a moderate stinger for most people, while others describe their encounter as quite painful.
Similar to many other species of jellyfishes, the Lion’s mane feeds on tiny ocean drifters, zooplankton, while they themselves serve as food for other species of jellyfish, some seabirds, leatherback turtles and the giant ocean sunfish, Mola mola. Certain shrimp, harvestfish and butterfish, unharmed by the jellyfish’s stinging cells, have been observed taking shelter under its bell.
The sea nettle jellyfish, with its 19-inch long thin tentacles lining the rim of its bell and four translucent ribbon-like arms reaching down from its middle, is a stunning beauty when encountered underwater or better still, from the opposite side of aquarium glass! The jellyfish is most commonly found in low salinity waters, ranging from Cape Cod to the Gulf of Mexico. The creature’s largest population, a subspecies of the sea nettle, is found in Chesapeake Bay.
Similar to all other jellyfishes, the nettle’s stinging cells consist of a harpoon-like structure that injects venom into whatever comes into contact with it. Once injected into the human skin, it can cause redness, swelling, blistering and pain. The sea nettle’s sting is not considered to be dangerous, but an individual’s reaction depends on the number of discharged stinging cells and the sensitivity of that person. The relatives of jellyfishes, corals and anemones, together called cnidarians, are also armed with stinging cells used for capturing their prey. Their stingers however, don’t penetrate human skin sufficiently to produce any harm. Worldwide, it has been estimated that yearly, well over 150 million people are stung by jellyfish.
The Portuguese Man-Of-War, a creature that resembles a jellyfish, is actually a colony of sea animals called hydroids. It is by far, one of the most dangerous jellyfish-like critter found on our shores. Held at the surface by a gas-filled bladder that is said to somewhat resemble the sail of an ancient warship, it is normally restricted to warmer Atlantic, Caribbean and Pacific waters. But occasionally, it catches a ride on the Gulf Current and then can become stranded on the beaches of southern New England to Florida. Similar to jellyfish, its dried-out tentacles can still inflict painful stings.
The box jellyfish, often called the sea wasp, is the world’s deadliest species of jellyfish. It is found in the coastal waters of northern Australia, New Guinea, Malaysia, the Philippines and Vietnam.
FIRST AID FOR STINGS: Peeing on the sting is definitely not recommended as first aid! The urine can actually discharge more stinging cells. Drenching the area with cool fresh water can also be harmful as is the application of baking soda, meat tenderizer, alcohol or rubbing the site with a towel. According to the Mayo Clinic, any tentacles remaining on the skin should be carefully removed with fine tweezers and not scraped off with a plastic credit card. Some claim that pouring salt water over the rash can be helpful, but rinsing the skin with vinegar for at least 30 seconds is much more beneficial. It is also suggested to follow up by emerging the site in bath water, heated to between 104 to 1130 F for 20 to 45 minutes. If a bath is not accessible, a hot water shower at the same temperature range can be substituted. Benadryl and oral or topical steroids can help relieve the swelling and itch, but if the reaction is more severe, you will need to immediately consult with a doctor.