The New York Times Bestseller, The Death and Life of the Great Lakes by Dan Egan, takes us through a comprehensive history of the Great Lakes and how we have impacted its delicate ecological balance. The Great Lakes holds 20 percent of the world’s supply of surface fresh water and provide substance, work and recreation opportunities for tens of millions of Americans. Egan chronicles successive invasions by lampreys, alewives and zebra and quagga mussels caused by our modification to the hydrology and ecology of the Great Lakes for shipping, waste removal and recreation.
A single Seaway ship can hold up to six million gallons of vessel-steadying ballast water that gets discharged at a port in exchange for cargo. And that water, scientists would learn after it was too late, can be teeming with millions, if not billions, of living organisms.
The book steps through the creation of the St. Lawrence Seaway which effectively opened the front door to the previously isolated Great Lakes. This allowed invasive species to “hitchhike” in the ships’ ballast water. To further allow for seafaring vessels to travel the Great Lakes other canals like the Welland Canal were constructed to by-pass other navigation barriers like Niagara Falls. This allowed invasive species to enter and spread throughout the Great Lakes previously protected by the geography of the St. Lawrence River (i.e. impassible rapids) and its great barrier, Niagara Falls.
Egan brilliantly explains how the changes in the ecology and hydrology of the Great Lakes are interrelated. He describes how each change has a ripple effect on the balance of the Great Lakes. For example, how the alewives affected native species forging on zooplankton and how the introduction of the salmon affected the populations of alewife. Everything is related.
The book reviews the current threats to the Great Lakes caused by the creation of the Chicago Sanitary Ship Canal. We have effectively opened a backdoor to the Great Lakes. This backdoor has become ground zero for the invasion of the bighead, silver and black carp currently decimating the Mississippi River system.
A normal lake is knowable. A Great Lake can hold all the mysteries of an ocean, and then some.
After all the doom and gloom, Egan concludes the book with proposals and discoveries that provide hope for the Great Lakes. We can learn from our past mistakes and work past geo-policial boundaries to protect one of our world’s most precious resources. I particularly found the idea of genetically modified species being used to cause a population of invasives to crash. Egan describes research showing that species can be implanted with a gene to force them to reproduce only male offspring for 3 generations. Stocking this modified species for multiple years could cause a population to crash. However, this comes with several political, ecological and ethical questions. Is it better to allow the Lakes to find their own balance with invasives or is it better to return it to a more pristine state with native species?
I highly recommend this book to anyone that drinks water in the United States.
If you live in the Great Lakes watershed or enjoy recreating on its waters, this is a must read. I highly recommend reading The Death and Life of the Great Lakes by Dan Egan.