Henry Chandler Cowles first stepped foot on the dunes of Indiana in the late 1800s while working on his dissertation for the University of Chicago. Studying the landscape, he noticed a progression in plant maturity that moved from the coast inland: barren sands became dotted with grass, and then shrubs and eventually forests. There, at the Indiana Dunes, Cowles first developed the field-defining idea of ecological succession, the process by which natural communities replace one another over time.
Cowles finally published his dissertation, “An Ecological Study of the Sand Dune Flora of Northern Indiana,” in 1898. But his love for the dunes continued.
Cowles dedicated his life to the landscape, bringing students there on field trips throughout his time as a professor. He also involved himself in conservation efforts, helping establish the Indiana Dunes State Park — which would go on to become something of a hidden gem and eventually even a national lakeshore in 1966.
“Those dunes are to the Midwest what the Grand Canyon is to Arizona and the Yosemite is to California,” wrote poet Carl Sandburg, in a letter to former Illinois Senator Paul Douglas in 1958. “They constitute a signature of time and eternity; once lost, the loss would be irrevocable.”
Appreciation, however, didn’t stop the impact of industry. In 1950, the Michigan City Generating Station coal-fired power plant was constructed by the shores of the Dunes — today, often mistaken for a nuclear power plant. The company has faced controversy for releasing “fly ash,” or liquid slurry, in water that flows to the lakeshore.
Just over a decade later, the White House compromised with local industry before establishing the national lakeshore, promising that alongside the park, another area would be used for integrated steel mills. Over 1,000 acres of central dunes were subsequently flattened by the Bethlehem Steel Company.
When Cowles saw the dunes, he saw the natural course of environmental change. Human development, however, has also caused change of its own.
The Indiana Dunes region has come to exemplify the complex relationship between wilderness and artificiality: marshes and steel mills, forests and smokestacks, dunes and city skyline. Industry, transportation and municipalities have fractured the boundaries of the park, sometimes creating ecosystem “islands” in isolation from one another.
Evidence also suggests that the Dunes may be “greening,” or experiencing accelerated growth from pollution-related nitrogen deposition. According to Noel Pavlovic, ecologist for the U.S. Geological Survey, chemical legacies remain in the park by Miller Woods, adjacent to the steel mill and landfill in Gary.
These realities echo warnings from earlier park advocates. Back in 1966, when the Dunes were first established as a national lakeshore, Congressman J. Edward Roush said, “If future generations are to remember us more with gratitude than with sorrow, we must achieve more than just the miracles of technology. We must also leave them with a glimpse of the world as God really made it, not just as it looked when we got through with it.”
Perhaps the strongest indicator of environmental damage is found in changing species composition. The Dunes remain a hub of biodiversity, but invasive species and climate change threaten vulnerable populations.
The Indiana Dunes stand at an overlapping point between different biomes. Arctic species like Jackpine grow adjacent to southern species like prickly pear cacti, while eastern deciduous forests thrive alongside western prairiegrasses.
“You have all these different ecosystems kind of colliding with each other,” Desi Robertson, the science coordinator for the Great Lakes Research and Education Center, said. “And so you have this incredible biodiversity where you find all these plant species concentrated in this little sliver along the southern shore of Lake Michigan.”
The biodiversity of the Dunes has been recognized as its key asset. Beyond aesthetics, it is essential to resilience against shocks like climate change and natural disaster. But climate-related disruptions may be threatening this safety net.
For example, Pavlovic described that record high spring temperatures in 2012 extinguished Karner Blue butterflies from Northwest Indiana. When the warmth caused eggs to hatch early, the lupine plants that Karner Blue usually eat had not emerged yet. Later, drought caused the lupine to dry out, killing off surviving caterpillars.
One 1991 report from the U.S. Geological Survey underscored the relative delicacy of the ecosystem, saying, “If our present climate changes, Indiana Dunes may well be one of the first places to reflect these changes.”
But the dynamic isn’t as simple as “man versus nature.” According to Robertson, the tension between natural and unnatural change is not necessarily as straightforward as we might think it is. For example, even during “pre-settlement” times, indigenous people modified the land with prescribed fires and agriculture. In other words, humans have been able to coexist with nature before.
“I think there’s this false dichotomy of natural versus human change. I don’t think you can go anywhere on this planet where people have not impacted it somehow,” she said.
Nevertheless, Robertson remains optimistic about the future of the Dunes. Because it is designated as a national park, staff have an obligation to protect its natural resources for future generations. For researchers like Robertson and Pavlovic, this means increasing biodiversity via prescribed burns, wetland restoration and treating invasive species.
“Indiana Dunes has this long legacy of scientific research,” Robertson said. “It has a lot of baseline data already. And because of that, we can build on that foundation.”
Robertson is currently collecting data on native bee populations and comparing it to earlier surveys. The research findings will help understand what habitat changes have impacted pollinators, which in turn impact plant communities.
“The park is making great headway in wetland restoration and controlling invasive Phragmites,” Pavlovic said.
“My hope is that we continue those efforts and grow them,” Robertson said, “and get to the point where we can go, ‘Hey, it’s hard to find an invasive species around here.’”
“We have kind of this dual mission,” she added. “We protect the resources for the enjoyment of the people. And we want to protect those resources so that they’re still here for the scientific legacy of this park.”
Nicely-written and very informative. I love the visuals, too.