The Death and Life of the Great Lakes by Dan Egan

One of the best conservation books I’ve read in a long time is the one that was our “assigned reading” for the GCA Conservation Study Trip to Lake Erie in September 2017.  It’s The Death and Life of the Great Lakes by Dan Egan.

Author Dan Egan has been writing about the Great Lakes for more than 10 years.  He knows his stuff and he’s able to present it in a very interesting and readable way.  From the early changes that humans have made to this extensive ecosystem beginning in the 1800s to the ongoing threats they face, Egan tells the story of one our most important natural resources in a way that both educates readers and inspires them to do what they can to preserve them for future generations.

The Great Lakes contain 20% of the world’s supply of surface fresh water.  This fact alone makes what happens to the Great Lakes of critical importance.  Add to that the large number of jobs and the possibilities for recreation, there are millions of people that rely on the Great Lakes for their livelihood and their leisure as well as for their water supply. 

For thousands of years, the Great Lakes were separated from the Atlantic Ocean.  Humans have made many changes in the past 200 years that have upset the ecological balance in the region.  The building of the Erie Canal in the early part of the 1800s first enabled non-native species like the sea lamprey and alewife, to decimate the population of native fish.

The construction of the St. Lawrence Seaway in the 1950’s allowed ships to sail across the Atlantic into the Great Lakes, bringing with them invasive species, particularly zebra and quagga mussels, in the ships’ ballast water.  These mussels have spread throughout the Great Lakes and into waters all over the US, littering beaches with their tiny, sharp shells and clogging dams and water systems.  Hundreds of millions of dollars are spent each year to try to mitigate the damage they cause.

Another man-made change that has affected the Great Lakes occurred in 1900. Building the Chicago Sanitary and Ship Canal reversed the flow of the Chicago River, allowing water from Lake Michigan to eventually flow into the Mississippi River. Instead of a natural barrier between the Mississippi drainage basin and the Great Lakes basin, the two are now interconnected.  Invasive species from the Great Lakes are affecting regions along the Mississippi and invasive Asian carp are making their way up the Mississippi into Lake Michigan.  A perfect example of the law of unintended consequences!

Algae blooms are another significant issue in the Great Lakes and other bodies of water.  Originally, the Great Black Swamp, the gigantic wetlands south and west of Lake Erie, filtered the water flowing into the lake.  This land has now been drained and turned into some of the most productive farmland in the country.  But it comes with a cost.  Farming methods are called into question with too much fertilizer, especially phosphorus, leading to an increase in a variety of blue-green algae called microcystis that is quite toxic at higher concentrations.  The water is unsafe to swim in or to drink when the levels of microcystis get too high.  

With all these significant concerns about the environment around the Great Lakes and beyond, are there any hopeful notes?  One interesting thing that has occurred is that the native whitefish in Lake Michigan have adapted to be able to digest mussels and alewives while Chinook salmon and other fish that were introduced for the sport fishing industry have not been able to do that.  It looks like some natural adaptation is occurring. 

The other solution posed by Dan Egan is to get young people engaged and passionate about the environment by providing them with firsthand experiences.  He did that by taking his young son fishing, getting him “hooked” in more ways than one.  Looking back on my own childhood, those times I spent outside playing and exploring helped make me more passionate about preserving the environment for future generations.  I’ll bet the same is true for many of you as well.