Return of the Jellyfish

 Vol. 10, No. 25

June 20-26, 2002

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Return of the Jellyfish

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Photo courtesy of the National Aquarium in Baltimore
by April Falcon Doss

Of all the Chesapeake’s creatures, the most hated is the stinging nettle jellyfish. We know them well, since our season for water sports is their season to thrive. Maryland’s lingering drought has brought us a Bay full of the saltier water that jellyfish love, which will translate any day now to a Bay full of jellyfish.

“Demon spawn,” I mutter, as I whisk my daughter out of the shallows where we wade, away from the sea nettle contaminating the shore.

The ambient temperature is 103 degrees; the heat index, 112. The only relief to be found is in the water, and the water has been invaded by demon spawn. “I’m sorry honey-pie,” I tell my three-year-old, who wants to get back into her float. “The water’s just not wet enough today.” The Severn River, evaporating under Maryland’s ongoing drought, is now the color of well-steeped Darjeeling, thickened with silt as if the tea leaves were ground to silken dust and suspended in the river. The salinity levels in the river have reached somewhere between 10 to 20 parts of salt per thousand of water, ideal for Chrysaora quinquecirrha, the stinging jellyfish that inhabits the waters of the Chesapeake Bay. The sea nettles have arrived two months ahead of schedule. I resent their interference with my summer-long aquatic plans, with my hopes for relief from the heat.

“Five hundred twenty-seven miles of shoreline in Anne Arundel County, and all of it infested,” I say to my daughter. “Time to step up the eradication plan,” I tell her. “Time to stock the Severn River with dolphins.”

The Best-Laid Plans
It travels in an aberrant direction, thronging perversely upriver, northward through the summer heat, against the current and away from the Atlantic Ocean. I have seen jellyfish, full-grown, whose bells spanned eight inches across, whose tentacles stretched six feet and longer. Eerily translucent, their color gives away the salinity levels of the surrounding water: The jelly’s bell-like medusa is reddish near the ocean waves and a streaky, milky white further inland, like egg albumin that’s only been partly cooked.

Jellyfish are more than 95 percent water. No bones, no brain, no real eyes. Sea nettles have no soul.

Ignoble, perhaps, but of ancient lineage. Scientists claim that jellyfish have been on the earth for over 650 million years, before there were dinosaurs and sharks. Which circle of hell did they populate, I wonder, before arriving here?

Jellyfish are resilient. At least one heavy-duty eradication plan — a plan that predates mine, that is — was implemented in the Chesapeake Bay in the 1960s, funded by no less a power than the United States Congress. Known as the Jellyfish Act, the legislation authorized the federal taxpayers to spend from $400,000 to $1,000,000 each year from 1968 through 1977. The purpose: “promoting and safeguarding water-based recreation for present and future generations in these waters,” specifically, by “controlling and eliminating jellyfish, commonly referred to as ‘sea nettles,’ and other such pests.”

Better living through chemistry was tried first. Unfortunately, the potions that would exterminate sea nettles were also toxic to everything else. Next, researchers identified a species of sea slug that devoured baby nettles. Regrettably, the sea slugs never reproduced in any significant numbers in the lab, and scientists abandoned slugging the Bay.

The most successful extirpation so far was perpetrated neither by Congress nor science, but by Mother Nature herself. In 1972, Hurricane Agnes reduced sea nettle populations in Chesapeake Bay to the lowest levels ever recorded. However, according to nettle researcher Jennifer E. Purcell, formerly of the Center for Environmental Science in Cambridge, “this method of control cannot be recommended.”

Still, these failures arise from logistics. I remain confident that a well-executed extermination plan would do a service to the entire ecological community of the Bay — and go a long way toward ensuring human health and safety.

Think I’m joking? The earliest recorded account of nettles in the Bay dates from 1750, when the Maryland Gazette reported that James Mitchell, an Annapolis man, “met with a singular and fatal accident” when he “became entangled in a great number of sea-nettles.” He drowned.

From time immemorial, nettles have harassed and annoyed commercial fishermen, who today wear goggles and long-armed rubber gloves when working the Chesapeake’s waters in late summer. They use separators to keep the teeming jellyfish out of the crab keepers where they hold their live catch; otherwise, the slimy mass will smother the crabs before they reach market.

The sea nettles in the Chesapeake are such a pestilence, in fact, that they are one of three species studied by the International Consortium of Jellyfish Stings. This scientific group also studies the box jelly, or sea wasp, dubbed the most venomous creature on earth. The sting from its 10-foot-long tentacles can kill a grown man in a mere 15 minutes of unspeakable pain; on average, it kills one person in Australian waters each year. This is the company sea nettles keep.

photo courtesy of the National Aquarium in Baltimore
A Modest Proposal
It is for all of these reasons, along with a fierce desire to protect our children, that I resolve to take action. It’s a modest proposal I offer: to stock the Severn River with dolphins.

According to a National Aquarium exhibit in 1999, one mustn’t dispose of plastic bags in open oceans, because bottle-nose dolphins get confused by the floating bags. Thinking the bags are jellyfish, the dolphins devour them, which then get caught in the dolphins’ digestive tracts, causing intestinal difficulty and even death.

As my husband and I read these Aquarium plaques warning of plastic ocean dross, I said to him, “Aha!

“Hmm?” He turned from the adjacent plaque.

“I’ve got it,” I said. “The final solution. We’ll be able to eradicate them at last.”

“Honey, you’ve leaped.” Shorthand for, What on earth are you talking about?

“Look,” I said, pointing to the display. “It’s perfect! Everyone loves dolphins; sea nettles suck. I doubt there’s a big lobby out there to protect the lowly nettle. Let’s start a campaign to stock the Severn River with dolphins. The dolphins can gobble up the nettles each year; children will be able to swim freely in the Bay; they can even swim with the dolphins if they get lucky. No one’s ever heard of any environmental benefit from the damn things. This is our chance to wipe them out.”

Dave was not looking at me. My voice had risen; I think he was checking to see if anyone else heard my rantings. He doesn’t embarrass easily, but still. An aquarium is just not the place you propose deliberate, premeditated extinction. Unless, of course, it’s sea nettles you mean.

The rest of the afternoon, I returned to the topic.

“Why not offer an Adopt-a-Dolphin plan?” I suggested. “It can’t be inexpensive to stock an entire river with marine mammals. And I don’t know that we could persuade DNR” — the Maryland Department of Natural Resources –— “to foot the bill. But if we could do it entirely with private funding, just think of the potential! Families up and down the Severn River could sponsor a dolphin. They’d get a picture of their dolphin with its name, maybe a T-shirt, a calendar depicting Dolphins of the Severn River each year. It would be a place to start,” I said. “We could do the test program here, then expand it to the rest of the Bay.”

As we lay in bed that night, I continued, bouncing off Dave my concerns about salinity levels: Would the dolphins truly feel at home? Do their favorite snack fish occur naturally in the Bay?

“What about the sanctity of all life?” asked Dave.

I look at him, annoyed. “These are demon spawn,” I replied.

Dave smiled and said something tolerant, like, “Yes, dear.” Before long, he fell asleep. I lay awake, honing my plans.

The Doss family enjoys the Severn River in pre-jellyfish season.
photo by Richard Falcon
The Providential View
The presence of demon spawn in our waters — rivers, creeks, inlets, coves, open Bay, that all look so pure and inviting — bothers me no end. How could a loving God permit such a pestilence? Why create, why allow, this venomous creature that has no apparent ecological purpose?

My research led me deep into the food web. Here in the Bay, we have a second kind of jelly, called comb jellies or sea walnuts. In autumn waters at dusk, they float near the surface, translucent and slightly luminous, the size and shape of a small egg. They are resilient and springy, kind of like an oversized Vitamin E capsule or an overheated semi-liquid gummy bear. They have no tentacles. They do not sting. They prove to me that divine logic does not require jellyfish to be malefic.

Comb jellies eat oyster larvae but are themselves eaten by sea nettles. The seemingly innocuous comb jellies do considerable damage to the Bay’s already tenuous oyster populations by devouring oyster spat before they can mature. I am taken aback when I learn that in a dry year, it appears to be sea nettles that come to the oysters’ rescue. Sea nettles love to eat comb jellies — out of pure spite, I have no doubt. No wonder: everyone must like the inoffensive comb jellies better, including God, I’m quite sure.

In a high-nettle year, sea nettle predation reduces the population of comb jellies in the middle Bay almost to zero. The nettles, despite being voracious eaters, do no harm to the oyster larvae: whenever sea nettles catch larval oysters, they spit the oysters back out, bivalve Jonahs to the nettles’ whale. With no comb jellies to eat spat, perhaps more oysters might grow. It gives me small comfort to know that nettles just-might-maybe benefit oysters. But do I like oysters that much?

Nettles suffer terribly in the Bay’s southern reaches. In those waters, whose salinity approaches seawater’s 31 parts-per-thousand, butter fish and harvest fish live caressed and sheltered by the sea nettles’ tentacles while the fish are young. When the fish mature, they turn on their jelly hosts and feast on their vital organs. The research doesn’t indicate whether the nettle suffers physical pain or the stun of betrayal.

Discovering this information nearly led me to abandon my eradication plan. I began to feel warmth and sympathy for the sea nettle, verging toward reluctant acceptance that perhaps, indeed, logic lived in the cosmic plan. Further inquiry, however, relieved me of those moral burdens: Sea nettles are a dread nuisance to a fish called the bay anchovy. The nettles devour the same plankton, fish eggs and larvae that bay anchovies eat; the nettles also eat the anchovies themselves. The anchovy is prime food for striped bass, bluefish and other Bay species. When nettles eat and out-compete the anchovies, I reason, my favorite recipes suffer, for the want of striped bass.

Enough research. I know the nettles stalk me. I know that I can’t eat the nettles in return. Medical literature reports that ingestion of jellyfish can result in abdominal pain, cramping and generalized urticaria — a synonym for nettle-sting-rash. It’s a culinary frontier I don’t need to explore.

An Elegantly Devilish Design
The National Aquarium in Baltimore notes that the potency of jellyfish toxins varies greatly among different kinds of jellyfish: “Some jellyfish, like the sea nettle, are only annoying and some, like the box jellyfish, are extremely dangerous if you come into contact with them.”

Only annoying? I wonder if the esteemed scientists at the Aquarium have ever had the kind of close encounter with a sea nettle that my friend Tracy did.

On Labor Day weekend, old schoolmates gathered for a crab feast on the Severn River. There had been adequate rainfall that summer, and we’d seen no jellyfish yet. If the water at marker 13, where I lived, showed no signs of contamination, then surely the water even further upriver, at Ski Island, would be fine.

Tracy, Dave and I puttered upstream in an 18-foot Donzi bowrider. The weather was perfect, 85 degrees and sunny with low humidity and — a rarity on a holiday weekend — the water was smooth enough to do some real water skiing. Within shouting distance of Ski Island, we brought the Donzi off-plane. Its hull settled into the water like an overweight man sinking into a Lazy-Boy chair.

“This is so cool. I can’t tell you how much I’ve been looking forward to this,” Tracy said as she donned her life vest and tossed two skis in the water. “I haven’t skied in years. We used to do it all the time on the lakes back home when I was a kid.” Tracy jumped feet first off the swim platform on the boat’s stern.

When she came up, she couldn’t see our horror. “Thank God,” I thought, “her eyes are closed.” Perched on her forehead above her right eye was the unmistakable milky-white blob of a nettle. Its bell was at least three inches across; it covered Tracy’s whole upper face. Its tentacles streamed down her cheek. As Tracy pushed back her hair, the tentacles entwined themselves with it and rested, lightly as a sigh, on her right forearm, wrist and hand.

“What is on me?” Tracy cried. She brushed and batted at her face and hair in the spasmodic, panicky way that nettle victims do. Thrashing in the water, held afloat by her life vest, she tried to break free of the stinging cells.

That’s the insidiousness of the nettles, you know: The more the victim struggles, the more engulfed in the stinging cells she becomes. It’s an elegantly devilish design. Each stinging cell, each cnidocyte, contains a tiny harpoon, called a nematocyst, sharp and fierce enough to penetrate even fish scales and crab shells. Triggered by physical contact with its prey, the nematocyst injects toxins into the victim’s skin. The activation of one nematocyst triggers the other stinging cells in the vicinity to sting as well. Suddenly, the harpoons of a single jelly are swarming its victim, penetrating skin, scales and shell, an entire hive of harpoons on alert.

The venom’s composition is diabolical, designed to injure, to stun and to kill. Nettle toxin consists of 10 to 30 substances labeled hemolytic, cardiotoxic and dermatonecrotic. Imagine gastric acid injected under your skin by a thousand prickling needles. Imagine it in your hands, your face, your eyes. Imagine that, in the sea nettles’ watery element, you can’t quickly run away.

Tracy didn’t have to imagine. While we watched, helpless, from the boat, Tracy was living my worst fears.

We offered to turn the boat around and put vinegar, meat tenderizer or baking soda on the stings. We offered to get her a papaya (a little-known remedy: the fruit contains papain, the same ingredient in meat tenderizer) and let her shower to be sure all the tentacles were off.

Amazingly, Tracy stayed in the water to ski. I guess she figured there was nothing else to fear, that the nettles had done their worst. When she was done skiing, we headed back. (No one else wanted to get in the water.) Tracy’s right eye was swelling shut, her face and arm were covered with long streaking welts, angry, red and swollen. Tracy showered, took Benadryl, and had a stiff drink. I doubt she’ll swim in the Severn again.

Karmic Justice
The bell of the jellyfish, the part that floats near the water’s surface, bears the scientific name of medusa, in honor of its resemblance to the Greek Gorgon Medusa, whose hair was a mass of writhing snakes. I don’t know what caused Medusa to perpetrate such evil, turning whoever looked at her to stone. It must have been a lonely life, though, destroying anyone who drew close.

I tell myself this to ease my conscience regarding my planned slaughter of the nettles. What a miserable existence they must lead. Nettles suffer from sleep deprivation of mind-numbing proportions: They are doomed to continuously feed and swim. From once every two seconds to twice every one, the jellyfish shrinks and expands its bell. It pulses upward with each contraction until the bell bumps the water’s surface. There, it spreads its tentacles and then sinks down, capturing food as it descends. Each tentacle works independently, stinging prey and sweeping the doomed creatures — fish and worm larvae, young minnows, bay anchovy eggs, shrimp and crabs — into the gastric pouches of the swimming bell, where the quarry is dissolved. Nettles even eat their own kind.

Even after Medusa’s death, a gaze from her head turned men to stone. Jellyfish beached on the shore still carry live penetrating harpoons. Until all the watery life-blood has dried out of them, leaving a glittery trail like a slug salted in the sun, the jellyfish still takes its revenge.

photo by Sandra Martin
Shamelessly Fecund
But really, you wonder, if you live north of the lower Bay, how many nettles can there be?

Plenty. Plenty enough that in late summer, a cubic yard of water from the West River, just south of Annapolis, may contain a dozen or more. Plenty enough to support a cottage industry of nettle nets to protect beaches and create sting-free pools in the Chesapeake’s infested waters. Plenty enough that windsurfers and waterskiers, men and women alike, wear pantyhose in the Bay. Inexplicably, the nematocysts that penetrate crab shell do not sting skin enmeshed in a layer of nylon.

Just how prolific are they? Shamelessly. Sea nettle reproduction is a marvel.

Nettles have taken to bell (they have no heart) the Biblical injunction to be fruitful and multiply, for they reproduce in two separate life stages and in two different ways. First, nettle eggs become larvae, setting down roots and turning into polyps, fixed and planted on the Bay floor, attached to the undersides of empty oyster shells or even to large grains of sand. While polyps, they reproduce asexually. They slowly migrate, leaving a sluglike trail of tiny cysts which will themselves become polyps.

From late April to early May, as the spring sun warms the Bay’s waters to temperatures in the mid-60s, the polyps elongate and multiply, strobilating or peeling off into tiny swimmers a few millimeters across, young nettles called ephyra. Within a few days of devouring small plankton and larvae, the ephyra acquire a more familiar shape: an ephemeral ring with short thin tenticular strands waving and a short body protruding vertically down.

The bell broadens as it develops into its final mature stage. The tentacles lengthen, streaming down in ever-increasing ribbons of death. At this fully grown medusa stage, the nettle is capable of killing and wounding prey. And at this stage, it reproduces again. The nettles begin producing sperm and eggs when the bell is a mere inch-and-a-half across. By the time the medusa is four inches wide, it sheds 40,000 eggs into the water each day. Ugh.

The Attack of the Demon Spawn
By mid-summer, the river water was thickening as the spring rains tapered off. I paced my swims by counting off laps in segments of 10-feet-per-piling, as I stroked my way back and forth alongside 120 feet of dock. I’d come to expect fish nibbling at my ankles if I stood in shallow water, and I reveled in the beauty of blue crabs swimming, not steamed.

Mid-stroke one morning, I felt my arm entwined with silken streamers. Strands of bottom grasses floating loose, I thought, until I felt the telltate burning pain. A jellyfish had ensnared my arm, ever more of its tentacles surrounding me as it tried dumbly to pull me into its bell for a snack, and as I tried to thrash my way free.

I no longer remember how I got out of the water, nor do I remember what happened next. I do remember calling in sick to work, sitting huddled in a chair, cold and nauseated, my head aching, feeling numb except for the swollen rash on my arm, a fire of unbearably tender itching. I felt light-headed and vacant and had difficulty concentrating, although my cognitive symptoms may have resulted more from the antihistamine I took to reduce the swelling and burning itch than from the jellyfish sting.

According to the medical literature, “systemic reactions can develop with local cutaneous findings.” These systemic reactions may “include weakness, headache, nausea, vomiting, muscle spasm, fever, pallor, respiratory distress and paresthesis.” Apparently, I was one of those. No mere sting or rash for me. The good news is that while “hypersensitivity reactions are common, anaphylaxis is rare.”

That afternoon, I stumbled back to the scene of my betrayal. There on the dock, where I had clambered out of the river, lay the saltwater tracings of a dried jellyfish’s remains. I gazed at the sun setting in front of me, and as it went down, I turned to greet the moonrise behind. A sudden dread came over me. I looked down: the water was rising, lapping just under the planks’ surface. Oozing up through the boards at my feet were bulbous, gelatinous globs.

My heart raced as I calculated the number of paces between my feet and the shore. With horror, I realized that the surging tide was swamping the beach. As a tentacle curled around the sides of the boards, I gulped. Even the house might not be safe.

I hurdled the jellyfish teeming up through the crevices at my feet. In a panic I raced, dodging waving tentacles and leaping over hundreds — no thousands — of blobs. In a photo-finish, I arrived barely safely on shore.

I awoke.

My next dream was about dolphins.

Copyright 2002
Bay Weekly