Fly Fisherman's Notebook
Kenneth Orvis Dilworth
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The original book that was stored away in my Dad's archives. This web version emulates all the original content with notes and text included. I'm made an effort to retain the original style, only updating for content and changes that were indicated, and included in Ken's notes.
CONTENTS
| Chapter | Page |
|---|---|
| Introduction | 1 |
| The Brown Trout | 2 |
| Insects | 3 |
| Mayflies and Fly Patterns | 4 |
| Caddis Flies | 5 |
| Stone Flies | 6 |
| Midges | 7 |
| Terrestrials | 8 |
| Minnows, Streamers | 9 |
| Rises to Look For | 10 |
| Conclusion | 11 |
INTRODUCTION
"They fasten red wool around a hook and fix to the wool two feathers that grow under a cock's wattles, and which in color are like wax. The rod they use is six feet long and the line of the same length. Then the angler lets fall his lure. The fish, attracted by its color and excited, draws close and... forthwith opens its mouth, but is caught by the hook, and bitter indeed is the feast it enjoys, inasmuch as it is captured."
DEANIMALIUM NATURA
(The Treasury of Angling)
by Larry Koller)
For all I know, everyone in this class could be classified as an expert fisherman. We are all striving to become better fishermen, and we love this sport which gives us a better outlook on life. It provides us with a way of forgetting the troubles and worries we encounter in this world of ours. Becoming an expert is a very desirable goal, but it is worthless if we lose our honor or our good manners in the process.
I have the good fortune of knowing some of the finest fly fishermen in the west. One of these men always releases every fish he catches so that it may live to fight again someday. I personally enjoy eating a few fish that I catch, except in places like Yellowstone, where I release all the fish I catch.
Being an expert is not so much the fact that we catch fish, but that we permit others to enjoy the sport. Having good stream-side manners is as much a part of good fishing as any other part. A few things we might do would be to never race to be the first one on the ...
THE BROWN TROUT
When a fisherman thinks of fishing on the Provo River, he usually thinks of the excellent brown trout population that the stream contains. Indeed, the brown trout was and is as fine a fish as ever swam in the waters of the Provo. It is appreciated by most anglers for its cunning and elusive nature, as well as for its fight.
Whether its sophistication was gained through long experience with the sportsman's wiles, or whether it was simply a gift of nature is not known, but the brown trout's craftiness is known by those who have tried to catch this fine fish.
Browns were introduced into this country a little less than a century ago, and from that original introduction have spread all over America, and eventually were introduced into the Provo River where they grew to monstrous size. Every year some are caught that weigh from 10 to 15 pounds, but a good sized brown on the Provo River will weigh from 2 to 4 pounds. Bigger fish are there, but they are hard to catch.
Brown trout spawn in the fall, and this is an excellent time to catch a big one on large streamers. Large browns may be caught on comparatively small dry flies, but usually the only browns that will be feeding on the surface will be young browns. Occasionally a sustained hatch of May flies or caddis flies will bring three and four-year old browns to the surface, but mainly these large browns feed only under the cover of darkness. Most insect hatches occur at night during the summer, and this is an...
INSECTS AND FLY FISHING
Philosophies on angling vary enormously. Most fly fishermen stick to a selection of flies that have a long history of success: Quill Gordon, Cahill, Light Cahill, Grey Fox, Royal Coachman, Red Quill, Hendrickson, etc., and they use a sampling of patterns that embraces the "imitation," "impressions," and "attractor" theories. These patterns will take all species of stream trout anywhere in North America—at times. In terms of the "right" fly, these fishermen are the most tolerant and broad—minded.
Farther up the scale are the anglers who discover by inquiry or observation, the most effective patterns for taking fish in the streams of their particular choice. As a rule, the choice of flies here becomes somewhat more specific and will include both "imitation" and "impression" theories in matching the naturals.
At the topmost level are those few scholar-fishermen who investigate the fly life of one particular stream, collecting naturals as they hatch, identifying them precisely, filling notebooks with the emergence dates of each species and the various times of day they appear, and with annotations as to type of weather, wind, humidity and barometric pressure coinciding with each appearance. Since there are several hundred species of May flies, Caddis flies, stone flies, and other insects favored by trout as food, this is an onerous task for all but the dedicated man.
The Treasure of Angling by Larry Koller
A fly angler must now decide just how...
INSECTS AND FLY FISHING
Anyone who has ever fished at all, soon learns that fish eat the darndest things. Their struggle to survive forces them to eat anything that happens to be available, and this includes plants, animals, and occasionally rocks, sticks, and metal. If you examine the contents of your catch, you find such things as insects, minnows, and even moss.
Fortunately the main part of a trout's diet consists of insects, for most plants are hard to imitate by anything other than a green woolly worm.
A trout's diet probably consists from 100 percent insects to about 50-35 percent as the fish increases in weight. Fish never totally stop eating insects, and this accounts for the occasional huge fish that is caught on a small fly. As a general rule the smaller fish feed almost exclusively on insects, and the larger three to five year olds will favor minnows and occasional insects. If you fish small dries, you will probably find smaller fish in your catch, but that may not be the important thing.
Since insects form such a great portion of a trout's diet, you will need to know a little about them. Not that you need to become a walking encyclopedia, having every insect within 50 miles of the stream memorized, categorized, and collected, for an angler can catch fish by just sticking to a limited selection of flies such as the Adams, Lt. Cahill, Quill Gordon, Royal Coachman, and others, and not know a thing about the insects they imitate. In fact these patterns actually...
MAYFLIES
This fly is the most important insect that fish feed upon. These flies vary in color from slate gray to almost pure white. These mayflies emerge when the temperature, and other conditions are met that permit them to complete their life cycle.
Mayflies hatch about noon during the winter; during the early morning and late evening in the spring and summer, and at night during the hot summer days. Some of the best times to find a hatch in the spring and fall is on those blistery days when it snows a little, and then the sun breaks through. Never pass up a good duck day if you want to enjoy some excellent fly fishing in the spring or fall.
It is enough to know that an adult mayfly begins its life cycle as a nymph, and that trout feed far more on mayflies as nymphs than as duns or spinners. It is a simple matter of availability.
The life cycles of stream insects are vitally important to the angler. It is always helpful to know that dark insects--the blue-gray duns, the little black stone flies--are early season flies; that the brown flies appear a bit later in the spring, that the pale, light-colored flies come still later and on into the summer. The Provo River has a hatch of brown caddis flies later on in the summer, but generally this rule holds true.
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A. Nymphs: Mayfly nymphs are 10 segmented and may be either the free swimming or the crawling type. They vary in size from about a size 8 to a size 18 or 20 (hook size, not shoe s...
WESTERN SUPER HATCHES
| Genus & Species (common name) | Size | Peak Emergences | No* | Pattern Name |
|---|---|---|---|---|
| Size Epeorus & Paraleptophlebia (Slate-wing Drakes) | #12-16 | June 1 - Oct 5 | 5 | Slate/Brown Paradun |
| Ephemerella inermis (Pale Morning Duns) | #16-22 | June 5 - Oct 30 | 1 | Slate/Brown Emerger |
| 9 | Gray/Yellow No Hackle | |||
| 11 | Dun/Brown Hen spinner | |||
| Heptagenia & Siphonlurus (Western Gray Drakes) | #10-18 | June 10 - Sept 25 | 2 | Slate/Tan Paradun |
| Ephemerella Grandis (Western Green Drake) | #8-10 | June 15 - July 15 | 1 | Slate/Brown Emerger |
| 8 | Slate/Olive Paradun | |||
| Callibaetis Species (Speckled Spinner) | #14-16 | June 20 - Aug 15 | 2 | Slate/Tan No Hackle |
| 13 | Dun/Cream Hen spinner | |||
| Ephemerella flavilinea (Slate wing Olive Dun) | #14-16 | 1 | Slate/Brown Emerger | |
| June 25 - Aug 15 | 8 | Slate/Olive No Hackle | ||
| 11 | Dun/Brown Hen spinner | |||
| Tricorythod... |
MASTER LIST OF NO. HACKLE PATTERNS
| No | Wing and Body Type | Wings | Body | Tails | Hackle | Hook Size |
|---|---|---|---|---|---|---|
| 1 | Slate/brown Emerger | Dark gray hackle tips | Brown | Partridge or wood duck | Dark gray | 8 or 10 14-22 |
| 2 | Slate/tan Paradun | dark gray hen | Tan fur | Gray hackle fibers | Dark gray fibers | 10-18 |
| Slate/tan no hackle | dark gray duck | Tan fur | Gray hackle fibers | None | ||
| 5 | Slate/brown Paradun | D. gray hen hackle | Brown fur | Gray hackle fibers | Dark gray | 12-16 |
| Slate-brown No hackle | D. gray duck shoulder | Brown fur | Gray hackle fibers | None | ||
| 7 | Gray/olive Paradun | Gray hen hackle | Olive fur | Gray hackle fibers | Gray or none for no hackle | 18-24 |
| 8 | Slate/olive Paradun | Dark Gray hen | Olive fur | Gray hackle fibers | Dark gray | 8-10 |
| Slate/olive no hackle | Dark gray duck | Olive | Gray hackle fibers | None | 14-16 | |
| 9 | Dun/brown hen spinner | L. Gray hen tips | Brown | Gray hackle fibers | None | 14-22 |
| Partridge or light gray hackle clipped top and bottom | ||||||
| Gray/yellow Paradun | Gray ... |
WESTERN MAYFLY DESCRIPTION
From Selective Trout — Doug Swisher and Card Richards
| Epeorus Longimanus | (Slate Brown Dun or Slate-wing Drakes) | (size 14) |
|---|---|---|
| NYMPH: | Habitat, small to medium size streams above 5,000 ft. on large rocks | |
| Body: | Dark grayish brown, light brown underneath | |
| Wing Pads: | Dark brownish black | |
| Tails: | Tan with dark brown markings | |
| Legs: | Tan with dark markings | |
| DUN: | ||
| Body: | Light gray with dark markings on the back | |
| Wing Pads: | Dark gray | |
| Tails: | 2 gray with dark brown markings | |
| Legs: | Tan shading to brown | |
| SPINNER: | ||
| Body: | Pale brownish, although can vary to reddish brown according to locality | |
| Wings: | Hyaline | |
| Tails: | 2 tan mottled |
| Ephemerella inermis (Pale Morning Dun or Olive Quill) | (Late season species) | (size 20-22) |
|---|---|---|
| NYMPH: | Habitat, gravel and aquatic vegetation in all speeds of water | |
| Body: | Dark brownish olive | |
| Wing Pads: Dark olive brown | ||
| Tails: | 3 brown with black bands | |
| Legs: | Brownish olive | |
| DUN: | ||
| Body: | Bright, light olive yellow | |
| Wings: | Light gray | |
| Tails: | 3 tan with dark brown at joinings | |
| Legs: | Light olive | |
| SPINNER: | ||
| Body: | Male-yellowish brown | |
| Female-yellowish olive | ||
| Wings: | Hyaline | |
| Tails: | 3 light tan with brown joinings | |
| Legs: | Olive tan |
INSECT HATCHING TIMES
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CADDIS FLIES
A very important fly, especially in the West. On many rivers it is probably more important than the mayfly. The Provo River has some very large Caddis hatches. These usually occur from the middle of the summer until September and into October.
Unlike the May fly which hatches from a nymph, the caddis fly hatches from a larvae. The caddis worm builds a small case for itself to protect it from things like fish, but this case does a poor job. Locally these larvae are called "rock rollers."
The species of caddis most prevalent in the Provo River is a medium brown type, but other caddis flies are present that range in color from dark brown to apple green. Their cases range from the common cone-shaped type formed of tiny pebbles to those which have cases formed of small sticks and those which are square.
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Suggested Fly Patterns:
Larvae: Caddis worm, Potts Sandy Mite, Lady Mite, Hare's ear, etc.
Adult: Little Caddis, Bivisible, etc.
NOTES:
When imitating the caddis fly, always catch a specimine, for if you try to match them by simply watching them fly you may find your immitation is too light or dark.
STONE FLIES
These flies are quite common on our western rivers and streams. On the average they are large, meaty flies that are very appealing to trout, but some species are quite small.
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The large dark brown or black "Salmon fly" average about two inches in length, and the small yellow stone fly may be one quarter or an inch. All of these stone flies are an important part of the trout's diet, but more so as a nymph, since this fly is largely out of reach to the trout after his transformation into an adult.
Suggested Stone Fly Patterns: (Match size & coloration)
Stone Fly Nymph (Black Chinelle body with red or yellow underbelly), Black Horsehair Potts Fly with orange belly and brown hackle. Mormon Girl, Gray Hackle Yellow, Double Renegade.
Dry Flies: Sofa Pillow, Muddler Minnow, etc.
MIDGES
These flies are a very important part of a trout's diet, but they are quite small and therefore require small hooks; from size 16 to 24. When trout are feeding on midges they will often ignore all else, even the larger flies that may be present.
Midges fly over the surface of the water in an appearance that, to some, resemble snowflakes, and for this reason, have been termed by many as snowflies. In this adult stage they are not very accessible to trout, but sometimes a wisp of hackle (white, gray, or blue dun) tied on an 18-22 hook and fished dry will work wonders. The best stage to imitate is the larvae stage. Midge nymphs made from fur spun on small hooks, brownish stripped peacock quill with brown hackle, and flies made with copper wire all imitate midges enough to have some excellent fishing.
Fish midge hatches with the dead drift method, but twitching the fly a little may also bring good results.
Midges are present throughout the year, but the winter, spring, and the early summer are the most common times when midge hatches will be present on almost all waters.
TERRESTRIALS
These insects are land insects that sometimes get into the water either by accident, the wind, or because a mating flight takes these insects over the water. At times fish can become quite selective when feeding on these insects, ants for example, and will take nothing else.
Terrestrials consist of grasshoppers, beetles, ants, bees, crickets, leafhoppers, etc. These insects need little introduction, and do not compose a great part of the trout's diet, except at certain times and places. Since they are relatively rare upon our streams, we can often use this advantage to our good fortune, for some of the flies that represent these insects hardly do them justice, but a big trout finds the temptation hard to resist.
NOTES: (Terrestrials present in area, possibility of fish feeding on them)
| Terrestrials Present | Date | Fishing Possibility |
|---|---|---|
MINNOWS, STREAMERS
The Provo River has a large number of minnows and small fish present which utilize the minute animal and plant life. These minnows are an important food for large predatory fish, and therefore, they form an important food link in the Provo River Fishery.
UTAH SUCKER - Catostomus ardens
This is the largest sucker in the Provo River, for some of them weigh well over five pounds. These are seen often on the section of the river near the lake during the late spring which is their spawning season. There can be seen digging in the bottom of the river for algae, bottom insect larvae, and plankton which is their main food. Trout and other fish eat this fish for food.
SPECKLED DACE - Rhinichthys osculus
Blotches and specks of darker color on a gray back-ground give the speckled dace its name. It averages two to three inches, and seldom exceeds four inches in length. This minnow is quite abundant in the Provo River, and it serves as a valuable native link in the food chain for trout. It is found mainly in swift waters and riffle areas of smaller streams. It spawns in spring and early summer and inhabits waters varying widely in temperature. In Yellowstone Park this minnow is often found in waters which reach 80° F.
LONGNOSE DACE - Rhinichthys cataractae
The longnose dace is greenish brown to dusky with lighter, sometimes silvery, sides. A narrow black strip usually extends from the tip of the snout to the eye. Males in the spring have orange-red lips and head u...
RISES TO LOOK FOR
Often when we are fishing a stream, we see the fish before we have the opportunity to fish for them. Sometimes we blunder into a pool and see the fish as they are leaving, but hopefully we will see them before they have the chance to see us. Often this involves seeing the fish as they are feeding on natural insects, which we call a rise.
THE SUCKING OR BUBBLE RISE: This fish is taking insects off the surface, and will take a properly presented dry fly. If the fish is a large one there will be a loud sucking sound and rings will radiate out from a central point. There will be bubbles present to mark the fish that has just taken a fly, and these bubbles may continue to come up for a few seconds.
THE DIMPLE OR SIP RISE: When fish are dimpling the surface it might mean small fish, but not always, for often a large trout can pick flies off the surface and hardly disturb the water. The fish simply sticks his lip out and sucks in the fly. Some dimpling fish are hard to catch.
THE ROLL OR THE GRAB: This is probably one of the most exciting rises, second only to the explosion rise. In this rise, the fish seem to roll in the water. Sometimes their whole upper body comes out of the water as they take the insect or fly, but usually the fish just makes a slow roll and takes the fly off the surface. Fish these rises. Often these rises go unnoticed for they take place frequently in shallow rapids. Once I almost missed the most exciting rise of a lifetime because I mi...
CONCLUSION
Angling is compounded of many things. First, there are the fish, and without the fascination for the creature, no man will ever become a fisherman. Some fishermen judge their success solely by the number of fish they have caught. Others seem to enjoy "outfishing" their friends, a practice which is like shooting all the birds on a partridge hunt, or running ahead of your companion to fish every hole before he has a chance to get there. A person who is constantly talking of how he used a certain fly or method to outfish another, is simply showing the type of angler he is. Anyone can catch fish. Many women have caught more and larger fish (my wife, for example) on their first try at fishing. The very first time I took my brother fly fishing, I gave him a rod and a selection of flies. He had a great time. He slapped the water with the line, snapped the flies off on the back cast, and jumped into the water to try to save a two-pounder that got away. All the while he was getting one strike after another, about three of us experienced fly fishermen couldn't get a strike, but seeing his enthusiasm was well worth the fact that we were not catching fish.
We go fishing to catch fish. Some people say they go to get away, to study nature, or to see the scenery, but I feel that these things are extra bonuses that come through enjoying the sport. Some say that with the increased pressure upon our streams we may have to sacrifice a few fish for a little scenery, but we can cat...
Appendix: i
A promotional poster for the "Advanced Fly Tying Course" taught at BYU in the early 1970s. Kenneth Dilworth also did the illustration for the poster.
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