Although you can fish for salmon in the Great Lakes, us Midwesterners consider them a delicacy. Restaurants fly them in daily from the Eastern Seaboard and Norway. Rarely ever do we eat a Lake Michigan salmon—especially at a fair price. I grew up hearing the legends of my grandfather catching salmon in the northern reaches of Lake Michigan, a byproduct of an intense Great Lakes fisheries initiative. The first stocking of the lakes happened forty years ago, long enough to establish the salmon as another part of the Great Lakes ecosystem.
It was a big surprise when salmon stopped their annual river run in the Kinnickinnic River, one of Milwaukee’s most ecologically strained waterways. Imagine people’s surprise when the salmon recently started coming back:
The revitalized salmon population comes as a direct result of Milwaukee’s watershed cleanup plan. City officials have been constructing green roofs, setting up rain barrels and buffering watersheds to stop toxic runoff before it pollutes the freshwater. These techniques have allowed the river ecosystem to reestablish itself and the wildlife is returning. Very simple cleanup plans like these are finding success across the nation.
I recently spoke to someone from Groundworks Anacostia about the cleaning up the Anacostia and the surrounding watersheds in Washington, DC. Groundworks places bandalog litter traps—barges that collect refuse without interfering with the ecosystem—on the Anacostia River to soak up refuse before it mucks up the river. Recently, a beaver had been spotted down the river from the DC watershed making a dam. There are few better signs of ecosystem health than wildlife returning and settling to a region.
But we have to ask the question: Why did the wildlife leave in the first place? Obvious answers would be that polluted watersheds destroy natural habitats (in Milwaukee, concrete fortifies the Kinnickinnic at points, which I find confusing because it facilitates runoff). Viewed through a more theoretical lens, the health of certain species of wildlife pertains to the preservation of their “umwelt”—an extension of an organism’s own personal ecosystem.
A German word, umwelt entered the lexicon in the 1920’s. It poorly translates to “self-world,” or the observable world of an organism occupying a certain habitat. For instance, since birds fly they occupy very large umwelts, whereas a tick that clings to a blade of grass occupies a very small one. The word somewhat-recently got an ecological treatment in T.F.H. Allen’s Supply-Side Sustainability, a book that suggests what we should sustain, and to what extent. He uses it to talk about the existence of certain species around army bases in the United States. Ground dwellers like prairie dogs and rare owl species thrive near the bases even though the army consistently tests weapons, drives tanks and flies planes. These issues don’t matter because the key aspects of the umwelt remain in tact, and the animals can occupy the landscape at their particular scale.
Combining these ideas, we can say that the beavers in the Anacostia and the salmon in the Kinnickinic survive through the preservation of certain key elements of their habitat. Trash disrupts the beavers' umwelt because it reduces fish populations and can prematurely alter the flow of a river (although beavers themselves are vegetarians, fish indicate river health). For the salmon, poor river flow and poor visibility affect mating patterns and force salmon to find other sites to spawn. Both the beaver dam and the salmon running are great examples of restoration in action, the confluence of great ideas, hard work and a little bit of luck restoring an umwelt. Groundworks Anacostia and the Milwaukee Metropolitan Sewage District focus on the overall health of the river, and let natural ecology do the rest.