The Lion’s Mane jellyfish, scientifically known as Cyanea capillata, is recognized as one of the largest jellyfish species globally. Its appearance is characterized by a distinct eight-lobed, saucer-shaped bell, which can range in color from light orange or tan in juveniles to deep red or dark crimson in larger, older specimens. From this bell extend numerous long, thin, hair-like tentacles, giving the creature its evocative name. The bell can measure over 2 meters (6 feet 7 inches) in diameter, and its trailing tentacles can reach lengths exceeding 36.5 meters (120 feet), making it longer than a blue whale.
Understanding Their Sting
The sting of the Lion’s Mane jellyfish is primarily a defense mechanism and a means to capture prey, generally causing a painful but not life-threatening reaction in humans. Upon contact, thousands of microscopic stinging cells, called nematocysts, inject venom into the skin. This immediately results in a burning, prickling sensation, followed by intense, localized pain that can radiate, often accompanied by redness, welts, and itching.
While discomfort is significant, severe systemic reactions are uncommon but possible. Symptoms may include muscle cramps, headache, nausea, vomiting, dizziness, or even difficulty breathing and heart problems in rare cases. The venom is designed to paralyze small prey. The severity of a sting depends on factors like the area of skin exposed, the duration of contact, and the individual’s sensitivity.
Where Lion’s Mane Jellyfish Live
Lion’s Mane jellyfish primarily inhabit the cold, boreal waters of the Northern Hemisphere. Their distribution spans the Arctic, northern Atlantic, and northern Pacific Oceans, with common sightings in regions like the English Channel, Irish Sea, and North Sea. While typically found in coastal waters, they can also drift in the open ocean.
These jellyfish usually remain near the surface, at depths of no more than 20 meters (66 feet). Their slow pulsations mean they largely depend on ocean currents to travel across vast distances. They are most frequently observed during late summer and autumn when they have grown considerably, and currents tend to sweep them closer to shore.
Responding to a Sting
If stung by a Lion’s Mane jellyfish, the initial response should focus on safely removing any remaining tentacles and alleviating pain. Carefully pluck visible tentacles using tweezers or a gloved hand to avoid further stings; never use bare hands. Rinsing the affected area with vinegar can help deactivate unfired stinging cells, or saltwater can be used if vinegar is unavailable, but fresh water should be avoided as it may worsen the sting.
After tentacle removal, immersing the affected skin in hot water can significantly reduce pain. Over-the-counter pain relievers like ibuprofen or acetaminophen, and antihistamines for swelling, can also provide relief. Seek immediate medical attention for severe symptoms such as difficulty breathing, extensive stinging, or stings to sensitive areas like the eyes or mouth. Common myths like applying urine, rubbing the area, or using alcohol are not recommended and can sometimes exacerbate the sting.