Jellyfish

There are certain, shared experiences that unite those of us who grew up on PEI. For example, getting storm-stayed in winter, going to the beach in summer, and having annual run-ins with Jellyfish!

There are at least three species of Jellyfish in the waters around PEI: the Lion’s Mane (Cyanea capillata), shown here, the smaller and more cinnamon-coloured Atlantic Lion’s Mane (Cyanea fulva), and the white Moon Jelly (Aurelia aurita). Of the three, the Lion’s Mane is the most common and the one swimmers are most wary of. (Contrary to popular opinion, Moon Jellies do sting but have shorter tentacles and weaker venom – and so much less impact – than Lion’s Manes).

And it is wise to be wary of Lion’s Mane. Those trailing tentacles are covered with stinging cells called ‘nematocysts’. Brush up against one, and you’ll trigger a harpoon-like needle to shoot out and inject a chemical cocktail of venom that causes a stinging, burning sensation. Because this is a mechanical rather than biological process, tentacles attached to dead Jellyfish and detached tentacles free-floating in the water maintain their ability to sting.

A Lion’s Mane isn’t trying to sting a human; we are far too large for it to eat! Instead, the Jellyfish is using its tentacles like a drift net, hunting small fish, crustaceans, zooplankton, eggs, larvae, and even other Jellyfish. Once a tasty morsel has been caught, the Lion’s Mane uses its oral arms to move the food to its mouth and digestive system within the red, jelly-like bell.

These Jellyfish live only one year and, when conditions are right, can become both large and numerous. Warm water and lots of food can lead to blooms of Lion’s Manes and other species, while favourable winds, tides, and currents can push them nearshore, creating headaches for beachgoers. While it’s hard to predict exactly when and where a Jellyfish bloom will occur, it’s a safe bet that we’ll be seeing them more often thanks to warming ocean temperatures.

And if you do get stung? You’ll want to avoid some of the most oft-recommended remedies. For example, testing has shown that rinsing with seawater actually causes more venom to be released; the only treatment worse that seawater was urine (for which I think we can all be thankful!). Rubbing with sand can also make things worse by causing any unfired nematocysts to release their venom. In contrast, rinsing with vinegar and applying heat (45C for 40 minutes) each significantly reduced sting severity.

For most of us, Lion’s Mane Jellyfish are an inconvenience rather than a real threat, but they are part of summer on PEI Untamed!