Jim, there's likely more than one way to skin this cat. I'm only suggesting we need to figure the best method(s) and get our asses in gear.
Higbean, I'm not certain what the damning aspect was. I would imagine that sufficiently high concentrations of algae could smother some creature, but I doubt all. My guess is it was a mixture of things that go part and parcel. Low oxygen, toxicity to some of the invertebrates, and no doubt a number of other things I'm unaware of at this point. The algae bloom pictured previously lasted for about 4 weeks during and after the application which was done about a mile east of where the photo was taken. The action involved the rental of a residential dock where a large tank was installed and the Sonar was fed into the river/reservoir via a steady but "controlled" stream. Their controls were a bit suspect. I'm told that use of aquatic herbicides has a tendency to cause a spike in nutrients due to decaying vegetation but don't have a clear understanding of that.
The things that stand out to the average person is the lack of fish, wildlife and fisherman that were relatively abundant prior to this event. Back before this happened we had more otters in the back yard than Jehovah's Witnesses knocking on the door. Anywhere from a couple to 10 fishing boats passing by on a daily basis, mostly bass fishermen. Another footnote in history....
