Dan Egan's 2017 book is "an engaging, vitally important work of science journalism."
Quagga mussels
The Death and Life of the Great Lakes By Dan Egan W. W. Norton, 2017, 364 pages
The Great Lakes were blissfully isolated from the rest of the world for 14,000 years, with a thriving, self-sustaining freshwater ecosystem. Water flowed from tributaries primarily into Lake Superior, wandering through Lakes Michigan, Huron, Erie, and Ontario, then out the St. Lawrence River to the Atlantic Ocean. Thanks to the Niagara Falls, nothing – fish or mammal or machine – could travel upstream, by water, from the ocean to the four upper lakes west of Lake Ontario.
Then human ingenuity and industry intervened. The Erie Canal was completed in 1825, connecting Lake Erie and the upper lakes to the Atlantic, via Buffalo and the Hudson River. The Chicago and Michigan Canal, completed in 1848, connected Lake Michigan to the Mississippi River. Finally, the St. Lawrence Seaway was completed in 1959 – a 2,500-mile system of locks, canals, and channels engineered along the St. Lawrence River that permits big cargo ships to travel from the Atlantic to all five Great Lakes.
The seaway was expected to usher in a glorious new age of commercial shipping throughout the Great Lakes. It also opened the door to invasive species that stowed away on hulls and in bilge water of vessels from all over the world.
Shipping volume hasn’t met expectations. Invasive species have exceeded expectations, with varying degrees of catastrophic consequences and remedial success. Canal and channel building certainly share the blame for this mess with “over-fishing, over-polluting, and over-prioritizing navigation,” says Dan Egan, author of The Death and Life of the Great Lakes.
Egan is a reporter for the Milwaukee Journal Sentinel and a senior water policy fellow at the University of Wisconsin-Milwaukee's School of Freshwater Sciences. He is a graduate of the Columbia Journalism School, and has twice been a finalist for the Pulitzer Prize.
Harrowing
Here’s a good summary of the book from a review in the Toronto Globe and Mail by Eva Holland (March 10, 2017):
[Egan’s book] “is a series of increasingly harrowing chapters about the many invasive species that have since colonized the Great Lakes…from sea lampreys and alewives to the insidious zebra and quagga mussels [and Asian carp]. Each section of the book builds on the next; each invasion knocks out another piece of the Great Lakes' natural puzzle, enabling the next plague, and so on. In Egan's telling, even well-intentioned attempts to 'fix' the lakes tend, inevitably, to backfire. And the consequences are not just ecological: The book documents the billions of dollars spent by Great Lakes ports to keep tenacious mussels from colonizing and blocking their water-intake pipes, and the fears in those same ports that toxic, even deadly, algae blooms could soon poison the water supply for millions of people.”
Holland says The Death and Life of the Great Lakes “is an engaging, vitally important work of science journalism.”
Plankton annihilators
Zebra and quagga mussels are especially destructive. Unchecked, they can literally suck the plankton out of the lakes, starving all the aquatic life in the lakes that depends on plankton as a food source – in other words, nearly all aquatic life.
Whereas the mussels invaded through the “front door” – the St. Lawrence Seaway – Asian carp now threaten to invade through the “back door” – the Chicago canals that artificially connect the Great Lakes with the Mississippi River system. Monster-sized carp eat plankton and wreck the food chain maybe quicker than mussels can.
Invasive species aren’t the only danger the lakes face. “For several days in 2014, Toledo lost its entire water supply to a toxic algal bloom,” writes Ian Scheffler in a Columbia Magazine review (Columbia University, Summer 2017). “The year before, the water level of Lake Michigan hit a record low, before surging over three feet in just two years, prompting floods in Chicago. The culprits here are familiar: agricultural runoff and global warming.”
Now, thanks largely to pampered agricultural interests in Ohio, chemical farm runoff flows into Lake Erie and forms algal blooms that resemble an “aqueous atomic bomb” each summer. Egan warns that Lake Erie, which provides the drinking water to 11 million people, could soon face “a natural and public health disaster unlike anything this country has experienced in modern times.”
Havoc and hope
“The book’s final chapters look to the near future,” says Robert Moor In a 2017 New York Times review, “when a combination of climate change, a growing human population and even scarier invasive species (the razor-toothed snakehead, a strain of toxic dinoflagellates known as ‘cells from hell’) will further destabilize the lakes’ already wobbly ecosystem.”
I believe (this is Dave Freedman, not Robert Moor) that over the next couple of decades there will be mass migration from drought- and flood-stricken areas of the USA into the Great Lakes Basin, where the climate is relatively stable. (I have a bachelor’s degree in geography.) The influx of population will be both a blessing (more power in Congress) and a curse (higher density, energy use, pollution, and stress on the freshwater resources).
Egan offers a slim ray of hope. Thanks to new policies requiring ships to flush their ballasts, the influx of invasive species has slowed substantially. If the invasions can be stopped, the lakes may have a chance to settle into a new ecological balance. Floating docks are helping to mitigate the swings in lake level. There are proposals to erect barriers to block Asian carp, and genetic engineers are trying to devise ways to render the carp infertile.
“Egan’s most convincing suggestion,” says Moor in the Times, “is that we should close the [St. Lawrence] seaway to all overseas freighters, those oceangoing ships nicknamed 'salties,' which inadvertently smuggle invasive species in their bilge-water tanks. It is a radical-sounding proposition, which the shipping industry vociferously opposes. But Egan shows that it is surprisingly feasible. It turns out that all of the foreign oceanic freight currently shipped to the Great Lakes each day could be brought in and out by a single locomotive.”
“If that train delivered as much ecological havoc as the salties have,” Egan muses, “it is unlikely the public would still allow it to be running down the tracks.”