New book documents how jellyfish are inheriting the oceans, with a lot of help from humans

By Marc Jampole

If even just half of what Lisa-ann Gershwin reports in Stung! is true, then many younger readers may be telling their grandchildren stories about the long ago days when humans caught ocean fish and ate them. Stung! gives the depressing news about how we’ve managed to pollute the oceans probably beyond saving. By beyond saving, Gershwin means a return to Earth’s oceans some 500 million years ago when disgustingly slimy and stingy jellyfish ruled.

Gershwin catalogues overfished areas, red tides, jellyfish blooms, heated and oxygen deprived waters, waters polluted by fertilizer and other human wastes and man-made catastrophes that collectively are killing many fish species and destroying the ocean’s delicate cycle of life.  She gives copious examples of all the problems we have created:

• Over-fishing, which means taking so many fish out of the water that a species is doomed to extinction.  Included in overfishing is the problem of bycatch, which occurs when fishing for one species leads to the capture and destruction of other species.  There is also bottom trawling, which essentially runs a large rake across the water’s floor, picking up delicacies like shrimp but destroying plant and other animal life.
• Eutrophication, which is a type of pollution caused by excessive fertilizer and sewage runoff causing an accelerated growth of algae and other plant life, leading to a disturbance in the balance of underwater life.
• Other kinds of pollution which causes deformities or contaminates fish and other sea creatures.
• The decline in oxygen levels in the oceans, which leads to the death of virtually all higher forms of life.
• The increasing acidification of the ocean, which dissolves shells. Particularly alarming is the fact that ocean acidification destroys diatoms, tiny creatures at the base of the food chain of higher order animals like fish, whales and penguins. Acidification also makes it more conducive for the type of tiny creatures upon which jellyfish love to graze.
• Climate change, which is warming the waters, again upsetting nature’s balance and leading to the imminent extinction of many sea dwellers.

As it turns out, each of these conditions makes the waters more conducive to jellyfish, since jellyfish can live in many environments and adapt well to a lack of oxygen.  Moreover, once jellyfish get a hold on a body of water, they multiply to the point of crowding out other life forms.

Stung! holds out absolutely no hope that we can fix the oceans. Gershwin’s last words in the book are “If you are waiting for me to offer some great insight, some morsel of wisdom, some words of advice…okay then…Adapt.”

But what does adaptation mean? I’m guessing that it means giving up on eating any creature from the ocean and figuring out how to eliminate the pollution from industrial fisheries, which right now contribute to the problem by dumping waste matter from production into the water. We’ll have to limit water sports to pools and other manmade structures, which we can keep clean of pollutants and jellyfish.  We’ll have to figure out how to keep jellyfish from destroying the filters of a variety of operations sited on bodies of water. It might mean developing technologies that actively clean carbon-dioxide out of the ocean water. It certainly will mean ending our dependence on burning fossil fuels, which is both warming the waters and injecting carbon into them.

Another recent book, Countdown by Alan Weisman, tells us what else we have to do: reduce the human population. We currently have about 7 billion people in the world and counting.

Some biologists think we can sustain 1.5 billion people living the kind of life we live in industrialized countries. My own back-of-the-envelope, seat-of-my-pants, pulled-out-of-thin-air estimate of the earth’s carrying capacity for humans is 1.0 billion. I pick that number because it’s the number of people on the earth in 1800.

My own belief—and it is only a belief—is that humans are so smart that we will survive, even if that means a return to living lives that, as Thomas Hobbes once put it, are “poor, nasty, brutish, and short.”  I assume that survival of humans will only come at the cost of a great decline in our population. My only question is whether war, epidemics, famine and chemical poisoning—the four horsemen of the Apocalypse—will cause the decline in our numbers or if we will take matters into our own hands and do it through birth control and family planning