Dirty Dan, are you maybe thinking of Orangethroat Darters? They were in a 2005 report from MI DNR as suffering declining numbers and they do show up as "species of concern" but not threatened or endangered. I couldn't get your link from post #6 to work, but I did manage to find that list at http://www.michigan....2._274586_7.pdf
This list went into effect in 2009. Darters on there, but no Rainbows. River Darters, yes, but no rainbow. The Michigan Natural Features Inventory from Michigan State University (2009)lists a few darters, including Orangethroats, but no Rainbow Darter. http://mnfi.anr.msu....imals.cfm#grp16
I am hopeful that you are mistaken in the Rainbow Darter's status. Which would make it more more easy to enjoy them!
Don't take this as criticism, because it is not. I applaud you for looking out for the fishes and wildlife of your state and being willing to speak out on their behalf. I'm just not convinced you have this right. But if you do, I like my crow served with a side of pride stuffing...