I have watched these buggers for decades. I don't qualify to answer your inquiry as I don't live downstream of TVA, but I'll offer some observations nonetheless.

Over the years I have noticed a wide variation in hatches from year to year. I can remember seeing them so prevalent that I have seen cars slide on them at night. I remember seeing one car do a 180 near Kykekr's in Kingston one night several years ago. I can remember having to knock them off the pumps to gas up. One particularly bad year I can remember having to drive in Meigs County and Bradley county, on highways running to the Tennessee River like Highways 30, 60, and 68. The things were so bad the roads were slick; it was like driving in a thick fog at night. It was dangerous. And played hell with being able to keep a windshield useable. My memory of noticing these swarms goes back to the 70s. I can remember in recent years that I have seen one or two on gas pumps and wondered where they were in their normal numbers. There seem to be more this year than in the last couple, although about 3 years ago they sure were plentiful. Made a feller wanna do some fly fishing!

And I can remember that the populations each year have been widely varying. This year the high level of moisture/rain has affected them, as drought also affects them in other years. While I certainly can't discount some possible effect that the TVA debacle may have had on populations in some areas, the lack of being able to isolate the situation makes it difficult to assign a causal relationship.

RB

I don't think aquatic insect nymphs are affected that much by rain cycles. The lake bottom pretty much stays wet. What can happen is that the rain is washing in sediment that interferes with the benthic habitat. We know that roughly ten miles of the Emory and Clinch have been covered by ash, though that varies by distance from mud zero.

I guess I would like to see a real study performed on this. It could be easy in some respects. Dredge nets could be used to sample for numbers of nymphs in a given area, etc.

When the willow flies are hatching, I could fly fish all day. You can fish under the Interstate bridge all day long, and catch something almost every cast. I missed it this year. For some reason, fishing just didn't seem like a good pass time.
My favorite spot is still covered with about 8 feet of coal ash. I'd say the willow flies won't be there for a couple of years.
I do know that in most places, the hatch seemed pretty much as good as it has been in the past. I believe next year will tell us the effects of the disaster relating to the hatch.

Funny you should ask this Steve, because Russ and I were commenting earlier this year about the fact that they were nearly non-existant at our house and we wondered about all the ash that's been in our cove affecting the population. We have lived here 11 years and every year we have had them so thick that I'd have to go out and sweep or blow off the deck in the morning. This year, nearly nothing. And Russ said to tell you what we did have was a month later then ever before. I have little tiny electric candles in some windows and smaller lamps in the house that I leave on all the time. I remember every year having to shut them all off at night or the window screens would be just caked in the mornings. This year I left them all on.

I'm not an expert, but I'd have to disagree on the rains affecting them because we've had a year or two where the water was so high our dock was underwater, but we still had the Willow Flies.

WC, thanks for the willow fly info. Did you take that nice photo? :)

Now I'm wondering whether the "little white moths" on which I've seen both raccoons and a bobcat feasting (Link...) are instead large white willow flies.

-- OneTahiti

To Lisa and others who leave lights on all night, may I be so bold as to suggest that any light you leave on all the time be a LED light, which uses a lot let electricity than incandescent or even fluorescent lights?

For example, I have a string of Christmas lights on the front porch tucked under the eaves (to avoid night light pollution) that emit just enough light for the unexpected visitor to be able to see the steps. We figured it cost us just a few pennies a year to keep them on all night.

We also have a white LED night light in the bathroom for you know what.

I would think after the fly ash disaster, you would want to bring down your electricity bill to "punish" you know who...

Here is a link to Wikipedia detailing everything you would want to know about LEDs:

Link...

to WhitesCreek: sorry I sidetracked your post on Willow Flies. My spouse says telephone poles used to get covered by mayflies when he was a kid (he's 7 years my senior). This year, because June and July were especially rainy in southern Quebec, we've had mayflies all summer, but not in the numbers that used to cover car windshields with goo. Also, 10 years ago, at this time of the year, I used to see Monarch butterflies in migration every 60 seconds or so, all flying doggedly SSW. All afternoon yesterday, I only saw one :(

to Lisa and OneT: my apologies for not thinking! All I have to worry about when I step out of the house at night in summer are skunks! Our friends in Georgia and Florida warned us enough, though, when we went down to visit. But it has been a while. Since Bush. But that's a story WhitesCreek probably would not like me to tell here... ;)

Canary in the coal mine. Insects are a great indicator of environmental health. So are some fish.

says they will have bulbs out in the 4th quarter of this year that will pay for themselves in less than one year.

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