What Trout Eat

What Trout Eat

When fly fishing for trout, you of course use fishing flies designed for trout fishing. So it is helpful to know what trout eat. They eat mostly anything they can get in their mouth that is a food group. Food groups can be classified into aquatic and non-aquatic or terrestrial groups.

  1. Aquatic groups are primarily the immature or mature stage of an aquatic invertebrate insect that lives the beginning of its life underwater, hatches to become an adult and mates. Then the female lays eggs back in the stream, lake or pond to hatch the next generation.
    1. The Mayfly, Caddis fly, Stonefly, & the Midge are the four classic categories of aquatic insects a fly-tier imitates. Each has 3-5 stages in its life cycle.  The underwater stage of an aquatic insect is the nymphal form, or commonly called a nymph. (1)

      There can be more than one underwater form, or stage such as larva & pupa. An insect that passes through 3 underwater stages to becoming an adult is said to have a “complete metamorphosis”—egg, to larva, to pupa, then emerges as an adult. (1)

      Caddis flies & midges typically have a complete metamorphosis. An insect that only passes through 2 underwater stages of egg & nymph is said to have an “incomplete metamorphosis”. Mayflies & Stoneflies have an incomplete metamorphosis. (1) 

      Of these the Caddis and Midges are the most important. The caddis is important because there are between 7,000 and 9,000 different species worldwide depending on which reference you consult. In any case there a lot of caddis for trout to eat. Midges are one of the most important trout foods because they hatch year round. If not for midges, many trout and other freshwater stream fish would not survive winters. During a midge hatch the water column and stream bottom may be alive with hundreds of thousands of these small insects. (2)   

    2. The other main aquatic group consists of prey or forage fish such as crayfish, sculpins, scuds, minnows, other young of their own and other trout species.  Fish eggs during mating season of other trout species. Browns follow the rainbow spawn and vice versa.
    3. Aquatic Worms that live their lives in streams are also a tasty morsel.
    4. Damsel fly and dragon fly nymphs and leeches are another main aquatic food group. Damsel and dragon flies are mostly a lake or pond insect while both lakes and streams have leeches.
  2. Non-aquatic food groups consist of terrestrial insects such as ants, beetles, grasshoppers, earth worms. In the spring, rains can wash earth worms into streams. In the fall, winds often blow ants, grasshoppers and beetles into the water. Grasshoppers in particular are a large meaty meal for a trout or bass.

    Mice and small ducks also are eaten by larger trout. Mice tend to swim from one place to another during the darkness, early morning or dusk hours. Large brown trout in particular will take a mouse pattern in a size 2 or 4. In some ponds, the trout may grow large enough to eat small ducks off the surface.


(1) High Plains Drifters FFF Club – Basic Fly Tying Manual – Reprinted with Permission
(2) Successful Fly Fishing for Trout Minicourse – Sign up for the course for more information on Trout Fly Fishing

 Flies to represent the major groups link to second article

Tight lines and Good Fishing,

Marshall Estes, Author
"Successful Fly Fishing for Trout"

Fishing Flies for Trout

Fishing Flies for Trout

You can carry a lot of flies and many fly boxes. Many fly fishermen do so. But we tend to be gearheads and often overdo the flies we carry. I carry four fly boxes in my chest pack. Three for nymphs and one for dry flies and several streamers. If you choose flies that can imitate more than one insect or life stage, it will cut down on the amount you have to carry. Listed are some of my favorite flies for the major insect groups. These flies will work in most western streams or lakes and many midwestern or eastern trout streams too.

  • Mayflies – Nymphs – an RS2 in grey, black or olive in sizes 14 through 24 will represent most mayfly nymphs during a season. A pheasant tail or gold ribbed pheasant tail nymph in sizes 16 through 22 will work for many other mayflies particularly the Baetis group. Another good emerger is Barr’s emerger for an all around Baetis nymph. A grey parachute Adams in sizes 14 thru 24 will work for a Mayfly dry fly. 
  • Caddis flies – my favorite is the beadhead goldribbed hares ear with a flashback or a turkeyquill wingcase. A plain gold ribbed hares ear with a cinnamon turkey quill wingcase is also excellent. Pick out guard hairs in the thorax to represent legs and give motion. The hare’s ear is a dynamite fly. Barr’s Graphic Caddis Emerger in tan and olive sizes 16 and 18 is another excellent caddis fly.
  • Stone Flies – The twenty incher, the beadhead goldribbed flashback hares ear in sizes 8, 10 or 12 and Pat’s rubber leg stone in sizes 6 through 12 is a hot stone fly. The rubber legs provide motion  and sound vibration to attract a trout’s attention. Pat’s rubber legs is one of the hottest flies around because it works. It is tied as a weighted fly. Use it as your point fly trailed by a beadhead hares hear or Barr’s Graphic caddis.
  • Midge – If I was only going to carry one fly for midge nymphs, it would be the bead head zebra midge or the black beauty. These flies in sizes 14 through 24 or 26 in grey, olive, black, or tan will cover about all the midge group of nymphs. Use a Parachute Adams of appropriate size for the dry fly stage. Or a Griffiths Gnat in sizes 20 and 22 works good for imitating a midge cluster.
  • Aquatic Worms – These are worms that live in the water year round. A san juan worm is a simple pattern in orange, red, light tan or brown. Use an ultra or micro chenille for the body. Cut a piece about 2 inches long, singe the ends closed with a lighter and tie it on the hook. Not much simpler than that. This is a good fly to learn when beginning fly tying.
  • Streamers – The Clouser Minnow in white and black or olive and black, muddler minnow and the Little Brown Trout would be some of my favorite streamers.
  • Teresterials – Dave’s hopper or the Charlie Boy Hopper are excellent patterns. Amy’s ant can double as a hopper or a large ant.

    Mice – take a Zonker streamer, tie the rabbit strip down to the hook, add some marabou to make a larger body, put some fly tying foam on top of all of it and rib with wire to segment the body and hold it together. Makes a fast mouse pattern. Black, grey or tan. A segment of rabbit fur could also be used to form the body and tail with the foam upper body. Or use mink fur and foam.

These are certainly not all the flies you will eventually carry but they will get you started with a good basic set for all season use.

Tight Lines,

Marshall Estes, Author
"Successful Fly Fishing for Trout"

Beginning Fly Fishing with Nymphs

Beginning Fly Fishing with Nymphs

There is a myth perpetrated on beginning fly fishermen that fly fishing with nymphs is really difficult. If you can bounce a salmon egg bait on the bottom with a fly rod and catch fish, you can catch trout with a nymph. The dead drift bouncing the bottom is a very similar technique. In my opinion, learning to make a perfect cast and a drag free dry fly drift is much harder than nymph fishing. You can make a sloppy cast and still make a good nymph presentation to catch trout.

In broad terminology, a nymph is the immature stage of an aquatic insect. Such insects form four of the major trout food groups.

  1. Mayflies – burrowers, clingers, crawlers or swimmers
  2. Caddis flies – Cased, net builders, free swimming
  3. Stoneflies – crawlers or clingers that hide under rocks or in the bottom gravel.
  4. Midges –  a major food group for trout. They exist and hatch year round. If not for midges, many trout would starve during the winter.

There are two main ways that nymphs can be used to catch trout. Sight fishing to a trout that you can see. Or prospecting for trout where they should be holding. Many fly fishers learn the prospecting method and never really learn the sight fishing method which is as challanging as dry fly fishing for trout. Especially when you are sight fishing nymphs for large trout.

Techniques for Prospecting for Trout:

  • If you take time to use an insect seine at each location on a stream, you will be able to see the predominate insect(s) in that area. You will also gain an idea of what dry flies to use should a hatch happen while nymphing. Choose a nymph fly to match the one insect that is most prevelant and a second nymph for the next most numerous insect. This will give you a good two fly rig to start fishing. While insect seining does not ensure a successful day, it certainly increases your chances over nymphing blind.
  • For blind prospecting, a beadhead goldribbed flashback hare’s ear is my choice of a point fly followed by a size 18 grey RS2 or an 18 Gregs Emerger. The hare’s ear represents, mayfly nymphs, caddis, and stone flies. The RS2 represents a mayfly or a midge. And the Greg’s Emerger is an all around emerger pattern. If a hatch happens, while I am nymph fishing, I will observe the insects a bit before switching to a dry fly. But if the trout are really keying in on the hatch, switch to a matching insect and have some fun.
  • In the early spring, nymphs of most species are larger in size and darker in color than later in the season. Example, some mayfly or stone fly nymphs will be very dark in the early spring and grow lighter as the summer progresses toward fall. This is where insect seining will help you to choose a correct size and color.


Nymphing is only as difficult as you make it. “Successful Fly Fishing for Trout” and the bonus books have much more information on nymphing for trout to help you become successful.

Tight Lines,

Marshall Estes, Author
“Successful Fly Fishing for Trout”

Nymph Fishing Techniques

 Nymph Fishing Techniques

Gear Description

Most nymph fishing is usually done using fly rods ranging from 6 ft to 9 ft or 10 ft depending on the size of the water and your target fish. I personally use a 9 ft 5 wt rod for spring and eary summer when the rivers are higher or for larger rivers. For my small stream fishing, I use a 7 1/2 ft 4 wt rod most of the time. Occasionally in the late fall a 6 ft 4 wt fly rod.  Generally small stream rods are for 2, 3 or 4 line weights.

Fly Reels should be matched to the rod weight. Four weight reel with a 4 wt rod and so on. Match your fly line to the reel and rod. The rod weight can be found just above the cork grip on almost all fly rods.


There are two ways to go with leaders. Use a manufactured tapered leader or build your own. Each has advantages and disadvantages. You have your choice of nylon monofilament leaders and tippets or fluorocarbon leaders and tippets.

  1. Start with a 7 1/2 foot tapered monofilament leader in 4X, then attach a 15 inch piece of 5X fluorocarbon tippet plus your point fly, add a 12 inch piece of 5X or 6X fluorocarbon tippet and your tail fly.
  2. Or you can build your own fluorocarbon leaders starting with a 0X piece of fluorocarbon and tapering down to 5 feet for the base leader. Adding a piece of 2X or 3X tippet plus a fly and a 4X piece of fluorocarbon plus a fly.
  3. For a nine foot rod, leaders should be no more than  10 or 11 feet and I prefer about 8 feet total. I have found a 1.25 times the rod length is about the max that handles well.
  4. From testing in the summer of 2010, I will say that my homemade fluorocarbon leaders helped me catch many more fish than using monofilament leaders with fluorocarbon tippets. (A whole leader of fluorocarbon sinks much faster than the combination does.)

Casts to Use

The two most used casts in nymphing are the Roll Cast and the River Cast. The roll cast takes some practice and is a muscular cast. When done correctly, it is easy to get a 30 to 40 foot cast. With practice you can shoot a roll cast to 60 or 70 feet. The roll cast is used when you have trees, bushes or other obstruction at your back. I also use it becase overhand casting of a three nymph rig is not easy and is tiring.

The River Cast is basically a lob cast using the stream current to load the rod for the cast. Finish your drift and let the line straighten out below you. With a sharp sidearm horizontal or 45 degree forward stroke toward your target load the rod. The let the rod pull the line off the water slinging it toward your target. With weight on the leader or using weighted nymphs, stop the rod at 90 degrees from your target because the line will roll over the rod at a 90 degree angle. For dry fly fishing, stop the rod pointed at the target and the line will shoot directly off the rod tip. Learn to use the river cast, it will save your arm when fishing for a full day on stream.

Where to cast:

  • Forty five degrees and upstream
  • Straight across
  • Straight upstream
  • Forty five degrees and across downstream
  • Straight downstream


  • Dead drift where you attempt to allow the nymph, line and leader to be moved by the current in a totally natural manner. The dead drift is best used when imitating insects that tumble helplessly in the current such as stone flies or burrowing mayflies. To do this you may need to use a reach mend, a pile cast, an S mend slack line cast, a curve cast or a hook cast. This is where some off stream and on stream practice will pay off.
  • The Leisenring Lift to reduce drag, impart some motion to the fly and move it up or down in the water column during the drift.
  • The Skitter and Twitch at the end of the drift.
  • The Mini-Mend to keep your fly drifting in the feeding lane. The mini-mend also imparts a bit of motion which may attract a trout’s attention.
  • The Tip Twitch and Wiggle during a drift. This is a very subtle motion but it sure gets trout.

Strike (Drift) Indicators or Not

When learning how to nymph fish for trout, using a strike indicator is helpful. An indicator can also be used to show you the currents so you can get a dead drift.

Types of indicators most often used are yarn, the plastic thingamabobber or an otter bobber. If I am fishing heavy water, I will use a 3/4 inch thingamabobber indicator and a 1/2 inch for smaller streams and in the late season.

Too often the beginner lets a strike indicator become a crutch rather than a tool. In more shallow water, try fishing nymphs without a strike indicator by making a little “J” in the line at the water surface. Let the “J” become your indicator. It is amazingly sensitive. A jiggle, stop, sideways twitch, set the hook. Most often you will have fish.


Nymph fishing for trout is only as difficult as you make it. “Successful Fly Fishing for Trout” and the bonus books have much more information on nymphing for trout.

Tight Lines,

Marshall Estes, Author
“Successful Fly Fishing for Trout”

Sunscreen vs Sunblock

In Colorado we get roughly 400 per cent more exposure to UV radiation than the midwest states do. So use of a good sunscreen or sunblock along with appropriate outdoor clothing is important while fly fishing. After having three operations for skin cancer in 2010, I decided to research if my current sunscreen was very effective.

All of the brands available at the grocery store or the big box stores had the same ingredients in them. The only difference was the percentage mix. What was missing was titanium dioxide which had been in most of them. Whether titanium dioxide was removed due to FDA ruling or cost was irrelevant. That ingredient was a key to preventing deep sunburn.

What sunscreen or sunblock is supposed to do is protect us from UV rays. Specifically UVA and UVB radiation. UVA will penetrate deep into the skin and cause premature aging and wrinkles. UVB is the one that produces the bad sunburns. UVC is almost totally filtered out by earth’s atmosphere. Both UVA and UVB are known skin cancer producers over long exposure.

Sunblock works by reflecting the UV off the skin. The two most used ingredients in sunblock are zinc oxide and titanium oxide in a very fine particulate form. The small particles reflect the sun’s rays off the skin.

Sunscreen works to filter out the amount of UV rays that penetrate the skin but not block all of them. This is done by using a combination of chemicals to filter out most of the UV from penetrating the skin. Unfortunately, the chemicals used are known to cause cancer, DNA damage, skin damage, be absorbed through the skin to damage internal organs and more.

The active ingredients in almost all sunscreens are:

  1. Avobenzone – toxicity buildup benzoic acid and other by products
  2. Homosalate – salicyclic acid concerns
  3. Octisalate – allergies and immune issues
  4. Octocrylene – cellular changes and biobuildup
  5. Oxybenzone – reproductive changes, cellular changes, bio buildup in the body, allergies
  6. Vitamin A Palmitate – Cancer causing when used in sunlight – One year FDA study showed a 21% increase in lab animals coated with the vitamin a palmitate lotion and exposed to only 9 minutes of Florida level equivalent sunlight at noon.

This is the active ingredient list. The inactive list is almost as bad for many sunscreens and sunblocks.

The best sunblocks still use titanium dioxide and zinc oxide in a nano particle sunscreen grade as the main ingredient to block UVA and UVB from penetrating the skin. They don’t use much else except for a lotion to spread the blocker around the skin. While most people don’t like the look or feel of zinc oxide or titanium dioxide, they do work. Which is worse not looking too good or having surgery to remove skin cancer.

Of course the best way to prevent sunburn and skin cancer is to stay out of the sun especially during the hottest hours of 11 AM to 1 PM. If you can’t be indoors, wear a hat of SPF cloth, long sleeve shirts of an SPF 50 cloth and a good sunblock on your face, hands and other exposed skin. A good hat is made by Tilley. Bass Pro’s World Wide Sports brand offers some excellent SPF cloth shirts and other clothing for reasonable prices.

The final result was the SPF 50+ sunscreen I had used for the last six years may have contributed to my skin cancer.

For an extensive evaluation of sunscreens and sunblocks
http://www.ewg.org/2010sunscreen/ This is a dynamic database of over 1,400 sunscreens and sunblocks listed by best by type and hall of shame products. There is more excellent information on this site about sunscreen studies and sun safety tips.

For safety coverup and wear a good sunblock.

Tight Lines,

Marshall Estes, Author
“Successful Fly Fishing For Trout”