From late spring through fall, three different species of jellyfish can be encountered in the waters of Long Island Sound. Found along the northeastern Atlantic coast and Canada, the Moon jellyfish, Aurelia aurita, is the most abundant jellyfish in the Sound. Easily identified, it has four distinct horseshoe-shaped reproductive organs on its bell. Translucent, the bell generally measures from four to 15 inches in diameter. Swimming by pulsating its bell, the creature remains near the surface. Armed with stinging cells, nematocysts, it captures mollusk larvae, developing crustaceans, young polychaetes, fish eggs and a host of other tiny marine animals. However, its stinging cells pose no threat to humans. When contacted, it produces only a mild burning or stinging sensation.
Calm waters and a midday sun sometimes reveal the colorful pale orange/yellow to reddish-brown lion’s mane jellyfish, Cyanea capillata. The cold-to-temperate species usually makes its first appearance in Long Island Sound during the early spring. However, it continues to be common in its waters throughout most of the summer. To the chagrin of bathers and fishermen, it is sometimes driven into sheltered coves or beaches where contact with it must be avoided.
Lion’s mane is regarded as the world’s largest species of jellyfish. In Long Island Sound, its bell is typically 6-12 inches in diameter with tentacles that can be from 10 to 30 feet long. However, in the Arctic Ocean, its bell diameter can reach 8 feet, and its tentacles can extend to 120 feet! Contact with its stinging cells can cause an instant prickling or burning sensation, followed by itchy red skin bumps. The jellyfish’s reputation as a nasty stinger played a pivotal role in Sherlock Holmes’ mystery, The Adventure of the Lion’s Mane. The famous detective was called in following the unexplained death of a science teacher. The victim had been seen staggering near a beach when he collapsed and gasped the words “the lion’s mane.” Though in some individuals, the jellyfish can produce a severe reaction, its toxin doesn’t compare to that of Australia’s box jellyfish, Chironex fleckeri. The sting from a large box jellyfish can cause death in humans within three minutes! It is considered the most venomous marine animal on earth.
Despite the lion’s mane’s formidable armament, the jellyfish plays a protective role for some juvenile fish, such as juvenile butterfish and whiting. The slow-moving jellyfish offers the butterfish a haven and a ready supply of food. Unharmed by its hot, stinging tentacles, the fish swims in and out of the umbrella’s underside. Leatherback turtles readily feed on the jellyfish.
The Atlantic Sea nettle, Chrysaora quinquecirrha, is found along the coast, from New England to Brazil. Along the Atlantic, they can live in salty ocean water and lower salinity estuaries. The jellyfish is especially prevalent in Chesapeake Bay. They are less common in Long Island Sound’s waters, where their population peaks between late July and September.
The sea nettle measures from 2 to 16 inches in diameter. Its overall length can reach 24 inches. Though attractive, its tentacles are armed with thousands of stinging cells that discharge on contact. It is not considered lethal for humans; it does cause a moderate sting and a rash that can persist for about 20 minutes. Young butterfish and small American harvest fish seek refuge within the jellyfish’s stinging tentacles; they even feed on their host’s tentacles.
Other species of jellyfish make their way into Long Island Sound, such as mauve stingers, crystal jellyfish, mushroom jellies, and cannonball jellies, but they are relatively rare. Two species of comb jellies, the southern comb jelly, ranging in size from 3 to 5 inches and the sea gooseberry, approximately 1 in long, are common to the Sound. However, they are not at all related to jellyfish. They lack stinging cells and belong to an entirely different group of marine animals.
FIRST AID FOR JELLYFISH STINGS
When tentacles come into contact with a person’s skin, the stinging cells discharge. They pierce the skin and inject their venom. The immediate sensation can be burning or stinging. It is then followed by itching and/or a bumpy rash. The rash may last for only a short time or persist for several days. Very rare symptoms can be nausea, vomiting, headache, or dizziness. If symptoms arise, such as difficulty breathing, dizziness, or severe pain, seek immediate medical help.
Immediately after contact with the jellyfish, the site should be flushed with seawater. Never use freshwater. It triggers the stinging cells, causing the release of their venom. Do not use urine, meat tenderizer, alcohol, or ammonia. Rubbing the site with a towel or applying a pressure bandage must also be avoided.
The tentacles should be removed with tweezers or a gloved hand. Some recommend using a credit card to remove them, but it must be done with caution. Lift them, but don’t scrape them off. If available, wash the site with vinegar before and after removing the tentacles. It is also recommended to immerse the site with hot water (104-113 F) for about 20 to 25 minutes to relieve the discomfort and deactivate the venom.