Food base is normal from what I have seen, there are plenty of scuds, sowbugs, midges, blackflies, black caddis, and still quite a few sulphur nymphs. It isn't a lack of food.
No signs of handling damage on any of the fish I reference, they all appear to be perfect other than a massive weight loss.
DO in the Clinch is great, and will always be great so long as the water stays cold as it usually does, and the weir is still in place.
1.) The food is there, is it in the same quantities as in years prior? I have no idea and it would be really difficult for most to determine whether it is or isn't. I don't know of a biomass size study ever being done on the river. So I personally don't feel food is an issue, if it were than the effects would show in all fish, not just the larger fish.
2.) I personally feel the atrocious flows TVA ran during the spring and early summer caused water temps to spike, resulting in lower DO, increased crap in the river (sediment/didymo), and less feeding opportunities for larger fish. Those factors which did happen could easily result in what is being witnessed on the lower river. As most probably know the larger fish prefer to feed during times of increased flow as it dislodges more bugs and feeding consumes much less energy.
I personally feel it all revolves around the flows the river had thrust on it for 3 months earlier this summer. Could it be a result of an over predation on the food source? Sure, and the trash fish (brook trout) would be a good place to start looking for a cause. Forever there was not the increased pressure on the food base which is now present with the introduction of another species. However, at the same time it may have no impact, and my disdain for the trash species may be clouding my judgement.