When I first started fly fishing, I had a hard enough time just learning what a dry fly was let alone what an emerger was. Back in the day it was all about floating an Adams or bouncing a Hare’s Ear along the bottom. There wasn’t a lot written about a stream’s ecosystem or entomology in the sixties. What most fly anglers learned, including myself was from time spent on the water and our own little network of fly anglers. I have always been an avid reader of all fly fishing literature and it wasn’t too long before I stumbled upon the phenomenon of emerging insects in some book or magazine. I didn’t understand at the time how important emergers are to a fly fisherman but I at least became exposed to the occurrence.
It really wasn’t until I started becoming interested in stream born entomology that the emerger phenomenon really started to make since. That there was a whole stage in the life cycle of a Mayfly that keyed a trout’s feeding behavior into a feeding frenzy was exciting and I needed to study it more. The problem was as a young fly angler raised in a town of bait fishermen I had little or no input on the subject from other fly anglers. To read about something as important and interesting as emerging stream born insects and not be able to talk about it with other fly anglers was frustrating to say the least. About the only picture I could get in my mind was a fantasy of what effect an emerger must have on a hungry trout.
So the next best thing is to have some emerger patterns in the fly box just in case I need to use an emerger should the occasion arise. So I managed to find a few unsophisticated emerger recipes from some of the magazines or books I had squirreled away and proceeded to add a fair number of new mayfly emerger patterns to my fly boxes. At least now I felt ready just in case I ever ran into some trout feeding on emergers. The problem for me was there’s more to emergers than just having a few patterns in the fly boxes for just in case.
I won’t bore you with the scientific details or the entomological significance of an emerging mayfly or caddis fly. I’ll leave that for you to research and study. What I will do is tell you that trout are only really interested in three stages of water born insect’s life cycle. Each of these stages can be identified by what section of the water column they are most prevalent in.
Stage one is the nymphal stage and this stage is generally almost always identified with the bottom six inches of the stream or lake. Stage two is the adult winged stage of a stream born insect’s life and can be found on or just below the surface of the stream or lake. Stage three is the emerger stage of the life cycle between the nymph and adult stage. This is the stage I’m most concerned with and the emerger can be found between the bottom and surface of the stream or lake. This section of the water column can be as little as one foot or ten feet deep. That’s a lot of water for an emerger to swim through and it’s that much longer in the cross hairs of a hungry trout.
Trout are for the most part lazy. They are not complex creatures of the water but characteristically pretty easy to figure out. Trout must eat, procreate, and stay safe from predators. Whatever is the easiest way to achieve those three things is how most trout will react. When it comes to feeding trout, the golden rule is whatever takes the least amount of energy to achieve a meal the trout will do. If it’s easier for the trout to suck in an emerging caddis fly then it is to try and chase one down on the surface you can bet the trout will take the emerger. At this point you can begin to see the importance of the emerging caddis fly to the trout. If you can match the emerging caddis fly with a good emerging caddis fly pattern you are going to have a great day on the water.
Of course, it’s never as simple as that. Conditions, timing and the water you are on all play some role in catching trout feeding on emergers. Sometimes you can plan a whole fishing trip around a hatch of mayfly’s that are supposed to be hatching on a river and end up fishing the whole time with an attractor fly because that famous mayfly hatch just didn’t happen. Or before you can figure out that the trout are feeding on mayfly emergers they switch to mayfly duns. Whatever the situation or whatever the water you are on, the conditions or timing was just not right.
In a worst case scenario, the trout may be feeding heavily on emerging mayflies and you suffer a brain freeze and don’t recognize it. That was pretty much my story. I fully understood the whole dynamic of emerging insects and how they play an important role in the trout’s diet but I just never had the opportunity to experience it and see it for myself. The trouble with being a self-taught fly angler is you must learn everything the hard way. Sure, I caught a trout here and there on some obscure emerger pattern but never quite put all the dots together so I could look at the whole picture. I can say, through a period of trial and error and a lot of on the water experience I finally became enlightened. For many people the road to enlightenment can be pretty easy and the whole concept of the emerging mayfly and how trout feed on them comes pretty easy, but for me it took a meteor from space to land on my head to eventually turn the light on upstairs.
It had been a long hot summer’s day on Silver Creek in Idaho and my son and good friend Bill and I took turns leap frogging one another along one of Idaho’s best spring creeks. We had each managed to catch a few trout on forget me flies and were feeling the effects of our physical exertion and the sun’s heat. Basically, we were beat. After a good amount of time sitting on the grass under the shade of a Cottonwood tree, we finally all agreed we would be better served if we hiked out to the truck for some cool beverages and a cold lunch.
As we hiked the trail back along the creek you could see from time to time a trout rise here and there but nothing to get excited about until we rounded the final bend to the trailhead. As I rounded the bend and get one last quick glance at the creek, I instantly stopped in my tracks and became transfixed on a truly magnificent sight. You see, as the creek wound itself around that bend it undercut the inside bank and about twenty to thirty trout were lined up like solders on a parade ground and were in a feeding frenzy. We stood there in silence until Brian started laughing. Soon we were all laughing and giggling at our good fortune.
The only problem we had was there was only enough room for one person to fish it without putting the fish down. I was soon assigned the job of representing our motley crew and in doing so was given the task of taking no prisoners. So as I thought through my strategy for the attack my son and Bill sat down on a convenient bench, stretched out their legs and began to watch the show.
After some time watching those rising trout and seeing no visible insect on the water it occurred to me that the trout may be slurping an emerging insect of some kind. The rising trout were exhibiting all the signs that lead me to that conclusion. Lots of slow rises where just the backs of the trout came out of the water and of course lots of trout fining were clues. All were telling signs of trout feeding on emerging insects. With trout feeding on the surface and no adult insects on the water, my first thought was to put on an emerging PMD which best represented the mayfly we were using throughout the morning. After tying on my PMD emerger and checking my tippet I slowly waded out into the stream into position for my first cast. That first cast could have been my last cast for the trout ignored every other cast after that. After numerous casts I could start hearing little snickers of laughter coming from the peanut gallery as if they could have done any better.
I think I used every kind of emerger pattern and size I had in my possession that day and never even so much as got a look. Finally, after giving up, I just held my rod under my arm and stared at the water for what seemed like hours. Then I slowly started to connect the dots. Just below the surface film were small size 22 drifting midge pupas. Nothing in my fly boxes even came close to that size. Like an old fighter not wanting to give up but not having the good sense to stop I just stood there shaking my head in bewilderment. It wasn’t until my son said,” Dad you’ve just been schooled” did I finally give up.
What I learned that day is that there are basically two things you really need to understand when it comes to emerger fishing. One is to let the fish dictate to you what they want and the other is to make sure you have all the right ammunition to do the job. What I mean by ammunition is you must have the right emerger pattern or patterns in your fly box. If the trout tell you they are feeding on emergers and you have a good copy of what they are feeding on, you will experience a great day of fishing.
Do a little research before going to the river for the first time. Find out what insects are on the water or hatching. Don’t be quick to hit the river fishing. Take your time, enjoy the moment and begin to study the water you plan to fish. What I mean by studying is maybe take some time to seine the water with a hand seine. It’s small and light to carry. It’s easy to use and its use can clue you in to what is going on under the surface of the water. Take enough time to study what’s happening on top of the surface. Are trout rising? Are there a lot of birds flying around? Are there any insects on the surface or flying around the surface of the river? If you see rising trout what are they rising to? What kind or rise forms are the trout making? Are they subtle and quite rises or are the quick and aggressive? Any one clue can make the difference between a good day’s fishing and a average day’s fishing. A quick study of the water you plan to fish can alert you to whether trout are gorging themselves with emergers or taking dry flies.
If you are going to a river or stream where a particular mayfly or caddis fly are hatching or in abundance, then you definitely should have a good selection of those dry fly patterns in your fly box. You should have a variety of colors and sizes, and a good selection of like patterns. This will insure you have all the right dry flies to do the job right. The same can be said for emergers. You should have the same selection on sizes, colors and patterns to match the emerging stage of the mayfly or caddis fly you’re trying to imitate. Be prepared for all three stages of the life cycle and you will be prepared for any contingency you might find on the water.
There are always exceptions to the rule, and nowhere can this be said more than in the sport of fly fishing. Almost nothing is worse to a fly angler then to be on a body of water around active feeding trout and you don’t have the right fly. I think that haunts most fly anglers and can be the driving force behind compulsive fly tying. However, having a good understanding of trout behavior and how they feed can take you a long way on that day when things are a little slow on the water. And a good insurance policy is to have on hand a good selection and sizes of emergers to go along with your dry flies.
Northwest School of Fly Fishing