I'd dearly love to see one in the wild.
QB, I doubt they were ever in the Buffalo. It seems like cool water is required for them. If I remember correctly, they only absorb oxygen through their skin. Cooler water can carry more oxygen than warm. They are also very likely to absorb any toxins in the water into their body. They need CLEAN, cool, heavily oxygenated water.
Ultimately, they may have to restrict access to certain areas of the upper parts of these spring fed systems. I think it would also help if they put some reasonable restrictions on streamside land owners. Ie you can't let you cattle beat down the banks. You cant plow to withing feet of the stream bank, you can't gravel mine and ruin the stream.
You would think owning land along some of the magical rivers we have in our area would make you value you them more than some ppl apparently do. I hate that folks chase the almighty dollar to the detriment of the creeks and rivers.