The New York Review of Books has a great review of Stung! On Jellyfish Blooms and the Future of the Ocean by Lisa-ann Gershwin. Jellyfish are getting moved around the world by ship ballast and causing huge damage to fisheries. We are also doing damage to their competitors. Read the whole thing.
From the Arctic to the equator and on to the Antarctic, jellyfish plagues (or blooms, as they’re technically known) are on the increase. Even sober scientists are now talking of the jellification of the oceans. And the term is more than a mere turn of phrase. Off southern Africa, jellyfish have become so abundant that they have formed a sort of curtain of death, “a stingy-slimy killing field,” as Gershwin puts it, that covers over 30,000 square miles. The curtain is formed of jelly extruded by the creatures, and it includes stinging cells. The region once supported a fabulously rich fishery yielding a million tons annually of fish, mainly anchovies. In 2006 the total fish biomass was estimated at just 3.9 million tons, while the jellyfish biomass was 13 million tons.
Humans are to blame in a variety of other ways as well. Overfishing of jellyfish competitors such as anchovies is helping the jellyfish wipe out other kinds of fish. We also cause oxygen depletion of water via fertilizer run-off. Jellyfish can out-compete other fish in low oxygen areas. The review outlines additional ways that humans are accidentally giving advantages to jellyfish.
Gershwin believes jellyfish are going to do catastrophic damage to the other species in the oceans. Scary.
“Read this book! You know that the oceans are in trouble, but this is the most comprehensive and clear explanation of why. Stung! is more than just a book about jellyfish; it is undoubtedly one of the best books detailing the stresses on our ocean ecosystems. It is a much needed and spectacular achievement.”
there are now 405 identified dead zones worldwide, up from 49 in the 1960s
Here is one I hadn't thought about before: the corn ethanol mandate (a subsidy for farmers masquerading as an environmental benefit) makes the very large Gulf of Mexico dead zone even bigger.
We need fish and healthy oceans. We should cut way back on allowed fertilizer run-off by shifting to different techniques to deliver fertilizer. We should also build marshes and other buffer zones between the farms and rivers.
|Share |||Randall Parker, 2013 September 06 10:00 PM|