Good article for others who might be interested in Great Lakes hydrology.....
.......I will tell you that the quagga muscles have been the most beneficial invasive species ever. More than the salmon intentionally introduced to control the alewife invasive species.
As a kid in the 60’s and 70’s, the Lake was becoming a messy. With both Chicago and Milwaukee on the same contained body of fresh water, this seemed inevitable. (The flow of the Chicago river was reversed for this reason in 1900 after a 13 year effort and much political strife since St Louis was competing with Chi for midwestern dominance and didn’t want Chicago’s refuse headed their way. And Milwaukee made virtually no effort at all to clean up its mess - even their new sewage system was simply constructed over the top of its old one resulting in sewage spills when storms overflow the system).
The water as a kid was greenish, and you couldn’t see deeper than 10feet deep. Alewives (an unintentional invasive brought by foreign tankers) flourished in the algae rich waters, but they have natural yearly die offs that resulted in the beaches being coated with the carcasses of millions of dead fish each late Spring.
The salmon were introduced to eat the alewives, and this worked beautifully. Not only did they control the population of alewives, they thrives, and a very lucrative and fun tourist industry popped up with game fishing.
Salmon began naturally spawning and self sustaining in the rivers of western Michigan.
Then the zebra mussels came. Boaters and fisherman were up in arms as they clogged their exhaust pipes and intake pipes, but the water began to clear. The game fisherman hated this because it limited the alewives food and thus the salmon’s food and thus the salmon numbers dropped and their size became smaller with less to eat. Thus the state began stocking salmon into the rivers each year - dumping in millions of salmon fry - and this worked to bolster the salmon for a while.
But then something happened.
The water kept getting clearer. I mean pristine clean. More than with the zebra mussels. You can now see down 40 feet, and the water is deep blue and clean. Despite Chicago and Milwaukee and growing population.
It turns out we have a new unintentional invader from ships - the quagga mussel. About the size of a dime, these things coat the bottom of Lake Michigan with trillions of them. Like the zebra mussels, they act as mini water filters - sucking out algae and impurities.
In the early 80’s while at ND, I heard Philippe Cousteau talk at the Library Auditorium about his findings after the Calypso had gone through Lake Michigan. His outlook was grim as he said that the bottom of the Lake was coated with a black ooze from the cities.
That ooze is now gone nearly 40 years later.
I share this because it’s interesting to me, and I’ve witnessed it first hand. I liked this article for those who are interested also.
Link: https://phys.org/news/2020-07-climate-asian-carp-threat-lake.html