Moon jellyfish, scientifically known as Aurelia aurita, are common sights in coastal waters across the globe. These invertebrates are easily recognized by their translucent, saucer-shaped bell, which can range from 2 to 16 inches in diameter. A distinctive feature of these jellyfish is the presence of four horseshoe-shaped gonads, often appearing in shades of pink or purple, visible through their bell. They possess many short, fine tentacles that fringe the bell’s margin. Moon jellyfish primarily feed on zooplankton and other small organisms, drifting with ocean currents as they have limited swimming capabilities.
Do Moon Jellyfish Sting?
Moon jellyfish possess stinging cells, known as nematocysts, located on their numerous short tentacles. These specialized cells contain tiny, harpoon-like structures designed to inject venom into prey. The moon jellyfish’s sting is typically very mild for humans, as their stinging power is generally insufficient to deeply penetrate human skin. The nematocysts are primarily used for capturing small food particles like plankton, not for defense against larger animals. Therefore, contact with a moon jellyfish usually poses minimal threat, distinguishing them from species with more potent stings.
What a Moon Jellyfish Sting Feels Like
A moon jellyfish sting typically produces a mild and temporary sensation, with individuals often reporting a slight pricking, tingling, or fleeting burning feeling on the skin. This initial sensation may be followed by minor irritation, itching, or temporary redness in the affected area. Sometimes, a faint rash or small welts might appear, but these symptoms are usually localized and tend to subside within a few hours. The experience is often compared to a light brush against a prickly plant or a minor insect bite, rather than a significant injury. Severe reactions to moon jellyfish stings are exceptionally rare.
What to Do After a Sting
If stung, exit the water to prevent further contact and to assess the affected area. Immediately rinse the stung skin thoroughly with seawater, not fresh water, as fresh water can cause unfired stinging cells to discharge more venom. Avoid rubbing the area, which spreads the stinging cells and worsens the irritation. Any visible tentacles remaining on the skin should be carefully removed using tweezers or a blunt object like a credit card, rather than bare hands, to prevent further stings.
After removing any tentacles, immersing the affected area in hot water can alleviate pain and neutralize the venom. The water should be as hot as the individual can comfortably tolerate, typically between 104 to 113 degrees Fahrenheit (40 to 45 degrees Celsius), for 20 to 45 minutes. Applying a cold pack or soothing creams, such as hydrocortisone lotion, can also help reduce discomfort and itching. Seek medical attention if symptoms worsen, spread rapidly, or if you experience signs of a severe allergic reaction, such as difficulty breathing, chest pain, dizziness, or widespread swelling.