SPITTING OUT THE BONES
When I was a kid we would occasionally have fish for dinner. When I questioned how to eat fish I was told that "You eat the meat and spit out the bones." Good advice for eating fish and many other things in life as well.
In my early days of fly fishing I was privileged to make the acquaintance of Vince Marinaro and to spend time fishing with him when he came to fish the Au Sable River in Michigan where I was living at the time. After I moved from Michigan to Montana we maintained our relationship through letters and cassette tapes. Those letters and tapes are some of my most treasured earthly possessions. Vince was one of the luminaries of modern fly fishing and his first book, A Modern Dry Fly Code, was just being rediscovered by the fly fishing public about the time that I first met him. That book presented many ground breaking ideas from the jassid to the crisscross hackled dry fly.
Vince was a spring creek angler, spending the bulk of his angling hours fishing the famous Pennsylvania spring creeks, especially the Letort. Vince was a tactician and his inquisitive mind was always searching for a tactical edge over his quarry; the wary trout of the Pennsylvania spring creeks. Through study and observation he became convinced that selective trout key on certain impressions that insects riding on the surface of the water create with their feet or bodies. He invented a new method of tying dry mayfly imitations that caused the imitation too keep the thorax and abdomen off the water. He called this style of tying "thorax style" which later came to be referred to as "crisscross" hackle. Vince was also convinced that the wing of a mayfly served as a triggering mechanism when the fly approached the trout's window so he tied mayflies with oversized cut wings.
Over the years in private conversations, letters and cassette tapes we discussed his theory in some detail. While he was convinced that trout use the impression that insects make outside of the window and the importance of the wing on mayfly duns when deciding whether something is edible, he was unable to account for the fact that trout eat conventional imitations that do not produce these characteristics. Although he maintained his support of his "thorax style" method of tying dry flies, in practice they proved to be no more effective than conventionally tied patterns.
For several years I tied a series of flies that consisted of nothing more than a tail, thread body, thorax and hackle. I varied the color of the tying silk, the thorax dubbing color and the hackle to emulate the insect that I was intending to imitate and in the smaller sizes – 18 thru 24 – they were as effective as fully dressed flies tied to imitate the same insects. I'm not certain what Vince would have said about those flies but clearly they produced solid rises and confident takes despite the lack of wings which Vince considered critical.
On a recent trip to the Bighorn River in Montana I was using a large [size 16] down-wing caddis pattern that is tied parachute. The post is pink so that it can be easily seen. I was using that pattern as an indicator for my much smaller [size 20] pattern that I was fishing as a dropper. The small fly represented the insects that I observed on the water but I hooked most of the fish that I caught on the caddis pattern, which did not represent anything that I saw on the water the entire three days that I fished there! Stomach samples, obtained with a stomach pump, produced nothing that looked like my caddis pattern, but nonetheless it was taken with gusto by several very nice wild trout.
The conclusion that I have drawn from all of this that, despite all of our observations and clever tying techniques, we still do not know what causes a trout, or any other fish to take our flies. We have our "theories" and our carefully crafted speculations and in many of these "theories" there is a modicum of truth. As with Vince's theory, fish may use the impression that an insect makes on the surface before the insect enters its field of vision [the window] to decide if it will investigate further, however the reality is that it's only one clue and not necessarily the definitive one. Flies that are tied according to Vince's method are rejected while a conventionally tied pattern is eaten with relish.
Fly fishing is an inexact science, if it can even be labeled as a science. If you are searching for a logical explanation for why fish react in a certain way you will end up frustrated because fish are not logical in their actions. When you entertain the latest theory or consider the latest killer fly pattern eat the meat, [the modicum of truth it may contain] and spit out the bones. Then go out there and have a good time.