Oliver and I escaped the busy thrall of the towns and cities for some excellent wild brown trout fishing this evening. This Highlands stream was so chilly that wading in shorts and wading boots, my feet and legs below the knees began to numb, even though temperatures reached the mid 90's today and really hadn't cooled off much. We found some surprisingly deep and wide water, but spots like these are rare and the trout important to release.
Oliver's much more experienced at this sort of fishing than I. He used a #22 dry fly to catch six browns, including two of about nine inches. My little six-incher fought hard on my new six-foot, two- weight. TFO rod. I felt impressed with this fish. This isn't really so different than catching 17-inch largemouths, since it's all relative and using an appropriate rod, leader, and tippet allows small fish to give a good account of themselves. I used 7X leader and tippet. This trout I caught and a couple of others I lost hit a #16 bead head nymph.
Mostly we fished a hole apart, Oliver going upstream to the next, and then I went to the next above him, but the most productive pool was large enough for us both to fish, only the trout seemed to want only the dry fly. Something hatched in minimal numbers, and Oliver said they looked like gray drakes. I think that's what he said. He first said something about caddis, maybe the gray drake is a form of caddis. Whatever the case, we did notice a few rising trout, just a few.
So long as water temperature remains below about 68 degrees, trout can be safely caught and released. I don't know at what temperature the line is crossed for each species, regarding lactic acid buildup during the fight and death after release when water is too warm. I got it from Chris Lido of The Fisherman magazine that 68 degrees is the line at which you should stop fishing trout if you plan on releasing them--which you should in wild and native trout streams, although eating a native brook trout in a lifetime is a very special treat. Browns tolerate the warmest water, rainbows second to warmest, brook trout coldest, so what the temperatures really are each species can tolerate a fight on a fly rod, I don't know, but I wouldn't fish any in water 68 degrees or warmer.
Some of our streams remain much colder than 68 through the entire summer. I remember diving headfirst into a deep Dunnfield Creek plunge pool on a 90-degree day in August. The water was so cold the shock overwhelmed me and I forcefully got right out. Spring emissions are about 55 degrees year round, and the Dunnfield is mostly fresh spring water, apparently.