Warmer-than-usual summer waters have attracted a non-native breed of large jellyfish to San Diego beaches for only the sixth documented time in 100 years, and experts from Birch Aquarium at Scripps Institution of Oceanography, UC San Diego, are being called upon to help explain the mysterious visitors.

Greater numbers of these delicate drifters, commonly called black sea nettles or giant black jellies, have recently been spotted in the La Jolla waters adjacent to Scripps, brought by a current from the south. What causes this phenomenon some years and not others, however, is still a mystery to scientists.

In early August, Birch Aquarium at Scripps aquarist Vince Levesque caught one of these giant black jellies while snorkeling just off the Scripps Pier. After capturing the specimen in a plastic bag, which holds enough water to support the animal’s weight while preventing the handler from being stung, Lavesque took it back to Birch Aquarium where it is now on public display.

Curiosity about the black jellies off San Diego shores spread quickly, attracting six television stations to the aquarium in one day for a rare on-camera glimpse of the live, giant black jelly.

“People have always been fascinated with the jelly displays at the aquarium,” said Bob Burhans, Birch Aquarium curator.  “With all of the recent local media attention, our black jelly has become extremely popular among visitors.”

The specimen Lavesque collected has a bell 12 to 14 inches in diameter. Its tentacles are between 2 and 3 feet long. While that size is impressive for this area, it’s modest in comparison with those found in pristine, tropical locales. There, animals have been known to grow to almost 3 feet in diameter with dozens of feet of oral arms and tentacles more than 12 feet long. In jellies, oral arms make up the innermost circle of lacy tentacles, which dangle down from the underside of the bell. These delicate arms pack lots of stinging cells, and when practically invisible pieces are broken off in the surf, they can be an unwelcome, secret stinger of swimmers.

How many times has jellyfish expert Lavesque been stung? “More times than I can count,” he said. So many times, in fact, that over the years his hands have built up protective calluses that allow him to handle most breeds of stinging jellyfish without any pain.

For the rest of us, Birch Aquarium aquarists say the best remedy for a sting is to wash the affected area with salt water or vinegar, and avoid temptation to rub the area. Rubbing will only dig remnants of stinging cells deeper into the skin and cause more irritation.

Despite their sometimes fear-inducing stings, Burhans assures that jellyfish are not aggressive toward humans, and should be appreciated for their unique, natural beauty.

“Jellies are really magnificent creatures. The variety of shapes, colors, and beautiful appendages make them one of the more fascinating ocean animals,” he said.

-Shannon Casey

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