I read an entire book on jellyfish, and it was worth every gelatinous minute. Here is my review, originally published on ecolitbooks.com.
Stung! On Jellyfish Blooms and the Future of the Ocean, by Lisa-ann Gershwin (The University of Chicago Press, 2013)
They’re here, and we’ve not just cleared out the guest room for them, we’re opened up the front parlor, the master bedroom, rumpus room, and kitchen. Soon we’ll be barricaded in the basement with a stinging, gelatinous substance dripping on us through the cracks in the ceiling. I’m talking about jellyfish. Our relationship with them has changed for the worse. As they fill our fishing nets and clog our nuclear plant intake valves around the world, they reflect our relationship with the entire eco-system. And now it’s time to say goodnight. DNA research has recently stripped the title of First Multi-Cellular Animal from the sponge and handed it to the jellyfish, and they might very well turn out to be the Last.
When I wrote jellyfish into the plot of Float, which was released in early 2013, I could not have imagined how dire the situation would get in such a short period of time. I was still thinking that if we could find a use for them — like turning them into a true bio-plastic — there might be hope. After reading Stung! by Lisa-ann Gershwin, I am not so sure about that anymore. No matter how many we harvest, more jellyfish will just bloom in their place, because the problem isn’t just that there are too many of them, it’s that they are the bellwether for a very sick ocean. As oceanographer Sylvia Earle writes in the intro, As seas become stressed, the jellyfish are there, like an eagle to an injured lamb or golden staph to a postoperative patient – more than just a symptom of weakness, more like the angel of death.
Gershwin puts jellies in the greater perspective of the general ocean health, discussing at length how jellyfish blooms (population explosions) are the result of degraded ecosystems as well as the driver of further decline. So a large part of the book is spent explaining, in layperson’s language but with the fastidiousness of a researcher, how, exactly, jellies are able to take advantage of even the smallest anthropogenic perturbation, the fancy word for manmade disturbances. These include the usual culprits of ocean acidification and warming climates from our carbon waste, pesticides, herbicides, fungicides, oil spills, leaching plastics, and radioactive material.
One of the worst perturbations is over-fishing, which creates imbalance, music to jellyfish ears if they had them. When a fisheries collapse, it’s not just the target species that disappears, every plant or animal that was dependent on it goes as well. Then its prey goes postal, causing a cascade of problems up and down the food chain. When the Bering Sea was fished out of Pollock by humans, the seals and sea lions disappeared, and the killer whales had nothing to eat but sea otters. When the otters disappeared, their favorite food, the sea urchin, ate up all the kelp forests, destroying the nursery for any remaining species, taking the seabirds with it. Enter the jellyfish to feast on the single-celled muck. An entire area of the Bering Sea is now called the slime bank. When the kilka, the main food fish of the beluga sturgeon, of beluga caviar fame, was fished to extinction, the sturgeon followed. Then who steps in? The mnemiopsis jellyfish, making any sort of re-stocking impossible, since they devour the eggs of both the kilka and sturgeon. They might not have caused the problem, but they prevent any cure.
Farmed salmon, already so bad for the ocean environment, was made for jellyfish, who bloom luxuriously by feeding on all the nutritious salmon poo. The situation is made worse when the swimming vortex of the caged fish sucks the jellies against the mesh and the fish are suffocated. No so the jellyfish, who can survive in very low levels of oxygen. It was the environment they grew up in, hundreds of millions of years ago. The same goes for warmer water. It is their natal soup. Jellies have withstood the ‘big five’ mass extinctions because they didn’t need to change as the environment warmed, and they will survive the next.
Jellies come in all sizes and colors and shapes, able to fill any ecological niche. Fifteen hundred species have been named and classified, with more being discovered on a regular basis. They have self-descriptive names: moon jellies, comb jellies, rainbow jellies, box jellies, fire jellies, sea wasps, sea nettles, sea tomatoes, sea walnuts, and on and on, including “the long stingy stringy thingy,” which is a wake-up call for budding scientists to take more creative writing classes. Some of them area as small as 1/5th of a grain of rice, others as large as a refrigerator. They are found in all latitudes and depths, all seasons of the year, with a few freshwater jellies thrown in the mix. Even Antarctica is changing to a jellyfish-dominated ecosystem. The demand for krill to feed fish farms has denuded the waters of the main food for penguins, seals, and whales. The jellies have taken their place, because they are able to eat the tiny phytoplankton known as copepods that have replaced the krill, but the others can’t. They are too small to see, but since the jellyfish don’t have eyes, and hunt by touch, they can. The same goes for the silt storms created by trawlers scraping the bottom of the sea beds for fish. Only jellies can navigate in the dark waters. The rest of the fish, meaning those not caught up in the trawl nets, starve because they can’t see their prey.
Speaking of prey, the omnivorous jellyfish can eat both high and low on the food chain. First by eating the eggs and larvae of big species, but also by eating the food that the larvae of that species would eat. This hat trick makes them both predator and competitor of species bigger, faster, and smarter than themselves. They can also survive long stretches of famine, shrinking in size until food is available again. When they are not eating, they are reproducing, often simultaneously. They can create more of themselves by hermaphroditism, self-fertilization, external fertilization, courtship and copulation, fusion and fission. This last is why cleaning the farmed salmon cages is futile, because it just stimulates more growth. They are not just prolific, they are practically immortal. Even putting aside the fact that cloning is a form of immortality, the cells of one species, Turritopsis dohrnii, reorganizes itself after death to form new colonies of polyps, the equivalent of a dead butterfly’s cells reforming into a caterpillar.
Jellyfish, what are they good for? Aside from a few good Asian dishes, which we might be well advised to develop a taste for, jellies have some medical uses. The discovery of a jellyfish protein that glows green won the Nobel prize in chemistry in 2008, and is used to track the growth of cells, mapping the neural circuits of the human brain. We’ll come up with more uses as time goes by, because one day, they’ll be all we’ll have to work with.
Remember the 1958 sci-fi movie The Blob, with Steve McQueen? Where an alien glob of goo takes over a town, and no one is listening to the teenagers until it’s too late? Think of jellyfish as the aliens. The teenager is played by Lisa-ann Gershwin, except that she’s stopped trying to get the adults to take her seriously and do something. Now she is calmly cataloging the cause and effect of the invasion for posterity. She believes that we have pushed the ocean too far, beyond a tipping point we never saw coming. The New York Times reported recently that the change won’t be gradual. Several human and natural systems are in danger of rapid and catastrophic collapse, meaning mass extinctions. Due to rising heat and lowered oxygen, the ocean is on its way to developing vast dead zones. No fish, no coral, no whales, no penguins, just algae and jellyfish. Lots of jellyfish. Radical simplification is what this is called, as the seas revert back to where they began. Gershwin has no suggestion beyond the single word: Adapt.