Clinging jellyfish invade Rhode Island waters

SOUTH KINGSTOWN, R.I. — Matt Rigby and Alorah Bliese pull up net after net filled with eelgrass and algae from the bottom of Potter Pond.

The two graduate students at New Jersey's Montclair State University dump the contents into a Rhode Island Department of Environmental Management skiff and comb through the tangled mess for animals hidden within. They pick out feisty mud crabs and delicate shrimp, slender pike and fat starfish, but two hours into their search on this late-August day, they haven’t found what they’re looking for: the clinging jellyfish, a tiny, near-invisible creature that resembles a delicate glass ornament but packs a walloping sting.

The invasive jelly has been spotted before in Rhode Island, but this past summer was the first time people reported getting stung, with three cases in Potter and Point Judith ponds, in South Kingstown and Narragansett, according to the DEM.

Not much is known about the animal here in the Northeast, so the agency welcomed the researchers from New Jersey who have been tracking the recent appearance of “clingers” in their state and around New England. One of their tasks is to figure out the exact types of clinging jellyfish that have been found. While people in Rhode Island reported painful stings and rashes, the cases in New Jersey have so far been more severe, with victims being hospitalized for respiratory and systemic reactions.

Whether there are differences between the jellies in the states is one of the questions that they and other researchers are trying to answer: Where did the species come from? Is its sting becoming more toxic? Is climate change playing a role in its spread?

“I think that each time we learn something new, it opens up a suite of questions,” says Annette F. Govindarajan, a biologist at Woods Hole Oceanographic Institution.

The Montclair State team found hundreds of the jellies a few weeks before in Potter Pond, yet, true to the animal’s confounding nature, it was proving to be elusive on this sunny afternoon.

The clinging jellyfish is named for its habit of using sticky tentacles to grasp sea plants in the underwater meadows it inhabits.

Native to the northern Pacific Ocean, it’s one of any number of invasive species that have appeared in places where they had never been found before as part of a trend that scientists expect to intensify as environmental conditions shift and ecosystems are thrown out of balance.

In the Northeast, think of the gypsy moth, which escaped from a failed silk-weaving experiment in Massachusetts, or the Asian shore crab, which probably arrived in the ballast of ships. Unlike the moth, whose caterpillar has defoliated forests, or the crab, which has displaced lobsters and other native crustaceans, the jellyfish long maintained a more benign presence in the region, its range limited and its numbers low.

But a spate of stings in recent years has spurred a concern that the species could become a menace to humans.

“It’s a public health issue,” says Paul Bologna, director of Montclair State’s Marine Biology and Coastal Sciences Program. “Are you going to let your kids go in the water if they end up in the hospital?”

Harvard naturalist Alexander Agassiz first documented large numbers of the species in kelp beds off Washington state in 1862. Clinging jellyfish showed up in Woods Hole, Massachusetts, in 1894 and were soon observed elsewhere around Cape Cod and Groton, Connecticut.

Theories abound about how the animal got to the Atlantic Coast. Perhaps jellies came in ballast water or as polyps — an early stage in their life cycle — attached to ships from the Mediterranean, which had gone through an earlier invasion of the species. They could have hitched a ride on oysters brought from Europe or on seaweed used to pack clams from Puget Sound. Curiously, scientists at the time never reported any stings from handling them.

Apart from a remnant group on Martha's Vineyard, the creatures all but disappeared in the 1930s when a wasting disease wiped out nearly all the eelgrass beds on the Atlantic Coast.

But in 1990, the first stings on Cape Cod were reported. Since then, the animal has spread to parts of New Hampshire, Rhode Island, Connecticut, Long Island and New Jersey. Globally, the jelly has turned up as far south as Argentina and as far north as Norway.

It’s unclear when the species arrived in Potter or Point Judith ponds, but it was found for the first time last June in the Narrow River, in Narragansett.

Because stings by clinging jellyfish were historically reported only off Russia and Japan, it's believed that different varieties of the animal exist: a toxic type native to the western Pacific and a harmless one in the eastern Pacific.

Pointing to the absence of stings in the Northeast before 1990 and the prevalence since, Govindarajan has theorized a second invasion of the species. But she doesn’t discount the possibility of a resurgence in the original 19th-century intruders, or even that there may have been a native population in the region all along.

“I don’t think any of the possibilities are mutually exclusive,” she says. “There could be several things going on.”

Unlike snakes or spiders, which deliver a single dose of venom using fangs, jellyfish inject innumerable micro-doses of toxin from barbs hidden in the stinging cells on their tentacles.

What does it feel like to be stung by a clinging jellyfish? Studies in Japan and Russia, where there have been outbreaks in which hundreds of people have been stung on a single day, list burning of the skin, difficulty breathing and liver and kidney problems. In some cases, the sting has caused temporary blindness or deafness.

The “Handbook of Clinical Toxicology of Animal Venoms and Poisons” describes “neuropsychiatric derangement in some victims.” The effects have been compared to Irukandji syndrome, a condition caused by the sting of box jellyfish in Australia that is characterized by a feeling of impending doom. Although symptoms from clinging jellyfish venom can persist for days, no deaths have ever been reported.

Mary Carman, a colleague of Govindarajan’s at Woods Hole, was stung on the face in 2013 and described the pain as similar to having “five hypodermic needles” plunged into her skin. A swimmer on the Cape suffered temporary paralysis after encountering the jelly. One man in New Jersey compared the sting to being jabbed with “a thousand ice picks.”

The first person to be stung in New Jersey suffered full-body muscle spasms, was put on a morphine drip, and spent nearly three days in the hospital.

“I thought I was going to die,” Matt Carlo told the Asbury Park Press.

Two years ago, Moise Solomon was swimming in Mumford Cove in Groton, Connecticut, when he felt as if he had been stabbed. He was taken to the emergency room with high blood pressure, an elevated heart rate and chest pains.

“I had never had such a reaction to a jellyfish sting before or afterward,” says Solomon, who has vowed to never again swim in an eelgrass bed at low tide.

As part of Bologna's research at Montclair State, he has stung himself with mushroom jellies and rubbed the still-toxic tentacles of a dead Portuguese man o’ war across his arm. He has been stung on the face by a lion’s mane jellyfish and says it’s considered a rite of passage in his lab to experience a sea nettle sting. Colleagues have prodded him to see what a sting from a clinging jellyfish feels like.

“With all the people I’ve met who’ve gotten stung, I know I don’t want to try it,” he says.

After launching from a boat ramp in South Kingstown back in August, John Lake, supervising biologist with the DEM, steers through the channel that leads into Potter Pond, passing Matunuck Oyster Bar and the summer visitors enjoying lobster rolls and fried clams on the outdoor terrace. 

Rigby and Bliese are making the second trip by the Montclair State team to Rhode Island. On the first visit earlier that month, Rigby and another student pulled up nets crowded with 10 or more clinging jellyfish at a time and found about 250 in all. The animals ranged in age, so even though the jelly typically lives as a free-floating adult for only a couple of months every summer, the researchers are expecting to find many more.

Jellyfish are not actually fish, but are members of a distinct phylum that includes sea anemones and corals. Unlike their cousins that float on currents in the open ocean, clinging jellyfish prefer waters away from the hammering of waves. Salt ponds offer a perfect habitat, where sea grasses are more common and where oyster farms may also offer shelter.

The creatures spend daylight hours at the bottom of the water column and come out at night to feed, swimming upward by contracting and extending their tentacles, then flipping over to catch small crustaceans called copepods and fish larvae to eat.

With the clinging jellyfish's transparent body, the internal organs are visible, forming the distinct orange-brown cross that Rigby and Bliese look for as they start scooping plants from the pond. They start in Seaweed Cove in the southern part of the pond and then make their way to Sycamore Cove in the middle part. At each stop, Lake takes temperature, dissolved oxygen and salinity readings. At each stop, there are no jellyfish.

“It’s hard to believe after we found so many before,” Lake says.

“Did we already go to the place where you pulled up a lot last time?” Bliese asks.

“This is it,” Lake responds.

At any one time last summer, Bologna had as many as 700 clinging jellyfish in his lab at Montclair State.

Inside two rooms cluttered with nets, waders and tanks filled with “jellyfish attracting devices” — tile squares with green ribbons attached to mimic eelgrass — he and his team have spent the last two years running experiments on jellies they’ve found around the Northeast.

The tanks are empty of the animals now, but Bologna keeps the water warm and oxygenated just in case easy-to-miss polyps left behind by reproducing adults are hidden somewhere. Nobody has been able to actively cultivate the animals, so the only way to grow them in the lab is by chance.

Until 2016, Bologna, a specialist in sea grass habitats, paid only passing attention to jellyfish. But at a conference that spring, he met Govindarajan and Carman, from Woods Hole, and they asked if he had come across clinging jellyfish in any of his field research. He hadn’t, but he promised to keep an eye out.

Two months later, an aquarium in Point Pleasant Beach, New Jersey, told him that a fisherman had found an unidentified jelly in a canal. It turned out to be a clinging jellyfish. Within days, the first sting in New Jersey was reported. Two more cases followed this past summer, both requiring hospitalization.

The New Jersey Department of Environmental Protection enlisted Bologna’s lab to find out more about the animals, and since then, he and his students have surveyed the waters around the state, finding more and more jellies as time goes on. They’ve traveled to Martha’s Vineyard and Connecticut to collect specimens. When Bologna heard about the cases in Rhode Island, he contacted the DEM.

Bologna believes the jellies may have been in New Jersey for a century or more, after tagging along on European ships in a phenomenon he calls “the Ellis Island effect.”  But their numbers were probably small and they went unnoticed, living out their short adult phase before the height of the beach season.

The right conditions for the jelly may have simply come together in recent years. One theory is that Superstorm Sandy in 2012 wiped out numbers of sea nettles — another type of jelly that preys on clinging jellyfish — leaving some coastal waters relatively free of a chief predator.

Just like the team at Woods Hole, the Montclair State scientists have found a genetic connection between some of the jellies in the Northeast and those found in north Asia. But they can’t explain why others found exclusively in New Jersey have slightly different genetics and whether that explains why the stings have been so bad there.

They also don’t know how the animal is spreading. Jellies are undoubtedly reproducing each summer, but where they leave the polyps that will overwinter and then spawn adults the following year is a mystery.

Jack Gaynor, a molecular biologist at Montclair State, says he recently saw someone selling a used dock and ominously imagined it carrying innumerable polyps to new waters. But he also says something as small as a piece of seaweed could do the trick.

Jellies are durable creatures, able to survive in higher water temperatures and lower oxygen levels that will kill their competitors — the type of conditions that are becoming more common as the climate changes. Jellyfish numbers have spiked in the Sea of Japan and the Mediterranean, and the animals are thriving globally. A recent study published in the journal Wilderness and Environmental Medicine projects an increase in the populations of certain poisonous marine creatures, including jellyfish.

When it comes to clinging jellyfish, Bologna is certain of one thing.

“There’s every reason to believe there’ll be even more next year,” he says.

With the sun waning in the hazy sky over Potter Pond, Rigby lets out an exclamation as he crouches over yet another clump of watery plants.

“Finally,” he says.

Wearing dish gloves for protection, he lifts out a glob of algae and picks it apart to reveal a gelatinous bulb about the size of a quarter with a telltale cross on its body. Squeezing a pipette dropper, he uses its suction to grab hold of the slippery jelly and then drops the animal into a glass jar, where it lazily pulses through the water.

An hour passes with no more clinging jellyfish found, so Lake steers the skiff back to shore. Rigby can’t explain why the animals disappeared. Maybe they just reached the end of their lives. Or perhaps some environmental factor changed. Temperatures spiked the previous week. Heavy rains may have played with the pond’s salinity.

As he unloads equipment from the boat, Rigby studies the single specimen. The jelly should have as many as 90 long tentacles, but it has far fewer, and the ones it does have are stubby.

“This one doesn’t even look that good,” he complains.

Lake understands the scientific value of finding more jellies, but he couldn’t be happier with the day’s meager catch.

“To be honest, I'm glad they're gone,” he says.

At least until next summer, when DEM scientists and the Montclair State team will be monitoring for any new signs of clinging jellyfish in Rhode Island.

— akuffner@providencejournal.com 

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On Twitter: @KuffnerAlex