I fish the South Fork of the Holston. For the past 3 years I have kept a journal of all my trips. I have noticed the Sulfur hatches are less frequent and with far less quantity. Three years ago, Sulfurs poured off, not so much now. I have ask the reason for the decline of local fishermen, biologist and entomologist. They have given reasons such as water quality, release schedules, number of degree days that cook the eggs and fish eating insect eggs. The more bugs, the more feeders.
This past week I talked with another entomologist, he offered the reason could be that as the number of insects increases so do the fish, bottom feeder aquatics and insects eating eggs.
This makes sense in some respects because there were hatches so strong it looked like snow. Fish eat the bugs and I suppose the eggs, bottom feeders eat the eggs and according to this expert, so do other bugs. This could explain the cyclical nature of the number and intensity of hatches on some rivers.
Does this resonate with anyone ?