Why a ‘storm’ of jellyfish took over Ocean City beaches this summer

Lindsay Walker, who grew up going to Ocean City, got stung by a jellyfish there for the first time this summer.

The waters were strangely calm this year, said the 49-year-old Baltimorean, who has been spending weekends in the beach town every month since May.

It was the calm before the storm, she said — before the ”storm of jellyfish.”

An unprecedented surge of jellyfish has disrupted vacations along Maryland’s coast over the past several weeks, with thousands of people reaching out to the Ocean City Beach Patrol for answers. The beach patrol is providing daily updates on jellyfish and other conditions amid the final weeks of summer. But many vacationers are choosing to stay out of the water, following warnings on social media. Experts say the jellyfish surge is likely due to a mix of factors, including drought and warm water temperatures.

Jellyfish are a common nuisance for swimmers and fishers during this time of the year. While there are several types of jellyfish in Maryland waters, the most prevalent in Ocean City is the stinging sea nettle. Many beachgoers consider August the jellyfish month, as water temperatures rise during the summer.

Walker said she could see the jellyfish in the water as she walked toward the ocean, dozens and dozens swimming about a foot away from each other. She got stung almost immediately the day it became too hot to avoid the ocean. Her husband got stung every time he went in, too, she said, to the point that he got used to it.

The number of jellyfish this year has been unprecedented, according to experts and city authorities. The city’s Surf Rescue team saw a large increase in the number of people reporting stings, said Butch Arbin, captain of the Ocean City Beach Patrol.

Months of drought, followed by a rainy spring and exceptionally warm summer, likely triggered the jellyfish bloom.

Nettles usually attach themselves to oyster beds, dock pilings and the bottom of boats in the beginning of their life cycle, said Megan Dunnock with the National Aquarium. Warming temperatures and rising salinity levels push them into adulthood, known as their medusa phase, when they go from larva to the familiar tentacled jellies.

Coastal waters reached 77 degrees in August, which makes this summer exceptionally warm, according to data from the National Oceanic and Atmospheric Administration.

The drought also led to low freshwater inputs, said Monty Graham, the director of the Smithsonian Environmental Research Center in Edgewater. Higher salinity and warmer temperatures yielded more food resources for jellyfish, he said.

It’s not surprising, he added, that the jellies that bloomed in the bays and estuaries would eventually be pushed out onto the open coast, especially with the recent heavy rainstorms and strong winds.

“This was a pretty banner year,” Graham said.

What to do if stung by a jellyfish

Jellyfish sting because they mistake people for food. The nematocysts — egg-shaped pill capsules on their tentacles — release barbs with toxins when they come into contact with another surface.

The toxins are injected through the top layers of the skin into the bloodstream. Most sea nettle stings are not considered “medically dangerous,” according to the Ocean City Beach Patrol, and stings can range from mildly to extremely painful.

Some people can experience an allergic reaction and should seek medical attention if they experience difficulty breathing, chest tightness, dizziness or swelling of the lips, tongue or throat.

The best thing to do when stung is wait it out, as the sting goes away on its own and relatively rapidly, Graham said. Pick off any piece of the tentacle that gets left behind and rub the skin with sand, he said.

The beach patrol also recommends rinsing the skin with seawater.