Ocracoke nature, flora & fauna
Lion's Mane. Photo by P. Vankevich

Lion’s Mane. Photo by P. Vankevich

September 2010

Spotted on Ocracoke: The Lion’s Mane
Text and Photo by Peter Vankevich

Two years ago or so, I featured in this column the Cannonball Jellyfish (Stomolophus meleagris) that had been spotted just off the beach at Springer’s Point. I noted that unlike many jel­lyfish, their toxins are rela­tively harmless to humans with little stinging capabili­ties. This month’s feature, an­other jellyfish (or these days also called “sea jellies”), goes by the curious name of Lion’s Mane (Cyanea capillata) and deserves a little more atten­tion in how it is approached as was illustrated in a rather bizarre beach incident that occurred up north earlier in the summer.

This species gets its name from its very long tentacles that some thought looks like the mane of a lion. It is par­ticularly noteworthy for being not only the world’s largest jellyfish but capable of grow­ing into one of the longest animals in the world, one specimen caught back in 1870 measured 120 feet, longer than a Blue Whale! The large crown, called the bell, can range from a diameter as lit­tle as five inches up to nearly seven feet. They are normally denizens of the northern cold waters of the Atlantic, Pacific and Arctic Oceans. On the Atlantic side, most of the year they rarely venture below the 42nd parallel, i.e. around Cape Cod. They will drift onto the Outer Banks, how­ever, when the waters cool in late fall and winter so it was a bit of a surprise to me to see this one beached near the Ocracoke/Hatteras ferry ter­minal on June 6, 2010.

Lion’s Mane feed primar­ily on zooplankton, small fish, ctenophores (when pro­nounced the c is silent), and moon jellies. On the other side of this food chain, its predators include seabirds, large fish and sea turtles. It is a member of the phylum Cni­daria (pronounced nigh-dar­ia, another silent c). A noto­rious trait of Cnidaria is that they have microscopic struc­tures known as nematocysts located along their tentacles which inject toxins into their prey. Nematocysts will cause variable degrees of stinging sensations when they come in contact with human skin which is a good reason to avoid touching them.

This species made quite a splash in the news earlier in the summer when it was re­ported that up to 150 people were stung by a large jellyfish on a popular beach in New Hampshire within a period of about one half hour.

So what happened? Accord­ing to several news reports, a very large jellyfish weighing up to fifty pounds with ten­tacles as long as 12 feet was spotted in the water among many swimmers. Lifeguards attempted to pull it to shore with a pitchfork resulting in breaking the tentacles into many pieces that ended up both in the water and on the beach.

People soon began complaining of itchiness and a stinging sensation. There was so much commotion that five ambulances and a hook and ladder truck showed up, and according to one report, the lifeguards were sent to local stores to purchase the recommended antidotes bak­ing soda and vinegar. No one was seriously injured, but a few children were sent to the hospital as a precautionary measure and released.

So what can be done if one encounters a Lion’s Mane on Ocracoke? Well the preferred method of removal would not be by pitchfork amidst a bunch of swimmers – an ex­tremely unlikely event on Oc­racoke. In fact, they are best left alone. If one is seen on the beach, avoid walking barefoot in the area since there may be pieces of hard to see ten­tacles around. They may still produce stings up to three or four days after breaking off.

If seen in water while swimming, move away from that immediate area. The sting of a Lion’s mane is not considered dangerous, but common sense dictates, like a bee sting, if one encounters symptoms that are severe such as dizziness or respira­tory distress after coming into contact with one, the person should seek medical atten­tion immediately.

This sea jelly enjoys a bit of literary fame thanks to one of Sir Arthur Conan Doyle’s Sherlock Holmes writings called The Adventures of the Lion’s Mane. This is one of the few stories narrated by Hol­mes himself rather than by Dr. Watson. (Doc. Watson is a much better story teller.) Hol­mes observes a man running from the beach in apparent distress mutters the phrase “Lion’s Mane” and drops dead.

The rest of the story in­volves eliminating suspects and concluding that that the killer was the jellyfish. Early on it was observed that the victim had a heart condition that saved Doyle from taking much more than a tad of po­etic license.