NATURAL FOOD ORGANISMS IN STILLWATERS
The subject of natural food organisms has filled many volumes, and there is no way that I can do the subject justice in just a couple of pages. Therefore the following will be a quick look at the most common food organisms found in stillwater fisheries. There is nothing special about stillwater food forms and, for the most part, many of these same forms are found in moving water as well. The difference is that the angler must learn how the trout feeds on these organisms in stillwaters and where they are found.
A breakdown of the most common food groups is as follows:
- Midges: worms, deep pupa, emerging pupa, adults
- Mayflies: nymphs, emergers, adults .
- Caddis: worms, cased, deep pupa, emerging pupa, adults
- Terrestrials: ants, beetles, hoppers
- Aquatics: snails, sowbugs, shrimp, backswimmers, leeches, tadpoles, crayfish, damsel fly nymphs & adults, dragon fly nymphs & adults, water beetles and minnows
Midges: Diptera‑‑these tiny (and not so tiny) two‑winged insects have been the curse of anglers for years. These insects inhabit stillwaters and hatch throughout the year and tend to cause anglers a fair amount of frustration. These insects have a complete metamorphosis. Trout in lakes and ponds feed actively on the larvae (a worm‑like organism), on the pupa as it breaks free of the bottom and starts to ascend, on the emerger as it hangs in the surface film attempting to emerge and on the adults. Lake midges can be as large as size 12 and smaller than size 28. The angler must carry a well-rounded selection of patterns to cover all stages of the midge. Midges inhabit extremely diverse habitats, from the shallow edges to the deepest water in the center of a lake. In their 1984 book Lake Fishing with a Fly, Ron Cordes & Randall Kaufmann say,
"More than 5,000 species of midges have been identified, with large parts of Asia still virtually uninvestigated."
Most often the heaviest midge hatches occur in the early hours of the morning or in the late evening hours. During cloudy days hatches can occur during the middle of the day. However, certain species do hatch during the late morning and early afternoon. Therefore one could safely assume that an angler could find hatching midges at any time (chuckle).
That last statement is called covering all the bases and creating confusion. Here in our area, midges hatch every month of the year that there is open, ice-free water. If an angler spends much time on a lake throughout the season, a schedule of the midge hatches can soon be determined. Many species of the larvae (worm) are free swimmers and are, at times, actively pursued by the trout. When the midge is ready to emerge, they must drift toward the lake's surface. During this time period they are preyed on, and again when they are hanging in the surface film trying to emerge. Remember, trout tend to feed on the food form which is most abundant and easiest to capture.
The key in knowing what pattern to use and when to use it is based on observation, experience, and a continued willingness to learn. Because of the sheer numbers of midges found in lakes, they are, without a doubt, one of THE MOST important insects for both the trout and the angler.
Mayflies: Ephemeroptera ‑ meaning short lived, winged insects. Most species have a life cycle of 1 year, though a few have 2 year life cycles. Many of the mayflies found in stillwaters are multi ‑ brooded insects. For the angler this means a protracted period of fishing mayfly hatches. Mayflies have an incomplete metamorphosis consisting of egg, nymph and adult. But the mayflies are unique due to the fact that the adult stage has two forms. They are the duns (subimago), which is the stage the angler sees when the fly is newly hatched, and the spinner (imago), which is the stage the angler sees as the mayflies return to the water to lay their eggs. These insects hatch from the water so the angler must be prepared with imitations for the nymph, emerger, dun and spinner stages to fish these hatches successfully.
The species most found in stillwaters are Siphlonurus (gray drakes), Callibaetis, Cloeon (olives), Caenis, Tricorythodes, Ephemera (green drakes) Ephoron (white drakes), and Hexagenia (brown drakes). Mayflies in the stillwaters will be found in weed bed areas, along drop ‑ off edges, in and around flooded timbers and in the silty bottoms. The water depth is generally never more than 25 feet, because that is the depth to which sunlight will penetrate. The mayfly hatches on most lakes are very predictable and one only needs to spend a season or two of careful observation to be able to chart the hatches on a favored lake or pond.
Caddisflies: Trichoptera - refers to the hairy covering on the wings; Tricho meaning hair and ptera meaning wings. The adults are easy to recognize as they appear to be moth - like and hold their wings tent shaped over the body. Caddisflies vary greatly in size and most of the area lakes and ponds have good populations of this insect.
Note: The larvae form of caddis found in the stillwaters are the case builders. The only exception where you will find any free living caddis larvae is in lakes that have a strong inflow, as the free living larvae need the currents moving over the gills for them to live, so free living caddis larvae are rarely a factor in fishing stillwaters
The caddis has a complete life cycle (metamorphosis) meaning that there is an egg, larvae, pupa, and adult stage. Caddisflies are 1 year cycle insects with the adults living up to three weeks. Trout will actively feed on the larvae, pupa, and adult stages of these insects.
Terrestrial Insects: These are land born creatures which end up on the surface of the water due to winds or just their own poor judgment. The insects of greatest importance to the stillwater fisher are hoppers, beetles and ants. During the warm days of mid - July to mid - October the angler may find the best dry fly fishing to be with imitations of these terrestrial insects.
Aquatic Food Forms: This group covers a lot of food organisms that the trout will feed on in the stillwaters. In some lakes certain forms of this aquatic food group become very important to both the trout and the angler. Therefore I will break down the aquatic food group giving you further information on the various food forms and their importance.
Minnows: Trout seldom pass up an easy meal and larger trout will often actively search for the larger food form like minnows.
Crayfish, Salamanders and Tadpoles: Many stillwaters have good populations of one or all of these food forms. Due to the time frame involved, the angler will find that all of these food forms have a definite time period where they will be effective. For the immature salamanders and tadpoles this is generally in the early months of summer between May and July. For the crayfish the angler will find the best time to fish these imitations is March to May and again in the fall, September to October, as these are the times that the crayfish molt and are then quite easy for the trout to capture.
Leeches: Offhand I can't think of a stillwater in the area which doesn't have a good population of leeches. Trout will feed on leeches throughout the season. Leeches vary in size from one inch to six inches long and swim with undulating motion.
Dragon Flies: Most stillwaters in the area have dragon flies and the trout will feed on the nymphs. Once in a while you will find a lake with a large enough population of dragon flies that the adults become important to the angler.
Snails: All stillwaters have snails and often times the trout will feed on these organisms. During windy days the wave action will often break the snails loose from the vegetation. During these times the trout really go after them. Also, during the summer months there will be a time period where the snails will float to the surface. During this period the fishing with floating snail patterns can be truly outstanding.
Backswimmers and Water Beetles: All stillwaters have populations of backswimmers and water beetles and at various times imitations of these organisms will produce some nice fish.
Sowbugs and Shrimp: Most stillwaters have large populations of these organisms and often these are the only major food group that is available to the trout in any quantity. Don't leave home without a good selection of shrimp and sowbug patterns!
Damsel Flies: Of all the aquatic insects, damsel flies provide some of the finest fishing to be found on many of the area stillwaters. The hatching dates for the damsels run between mid-June to early August. The trout actively feed on both the nymphs and the dries. Imitations of the damsel nymphs, dries and drowned adults are a must for the stillwater angler in this area during May, June, July and August.
For those of you who wish to further study and identify the organisms which inhabit stillwaters, I will break down the major groups into the various classes or orders, listing some of the most common genus (families) found in area stillwaters.
Class: Crustacea
Order: Isopoda (Sowbugs)
Order: Amphidoa (Scuds, Shrimp)
Order: Decapdoa (Crayfish)
Class: Insecta
Order: Trichoptera (Caddisflies)
Order: Ephemeroptera (Mayflies)
Order: Odonata (Dragon and Damsel
Order: Diptera (Midges, Crane Flies & House Flies)
Order: Hemiptera (Back Swimmers)
Order: Corixidae (Water Boatmen)
Order: Coleoptera (Adult Water Beetles)
Order: Gastropoda (Snails)
Class: Annelida
Order: Hirudinea (Leeches)
Order: Oligochaeta (Aquatic Earthworms)
COLLECTING & CHARTING
HATCHES & AQUATIC FOOD FORMS
Often I am asked, "Why should I bother with collecting the bugs?" By collecting the various food forms in any stillwater the angler can quickly build a knowledge base that will assist in knowing what imitations to fish, how to fish them and when to fish them. The collecting and charting of the food forms will take a little work on the part of the angler but the rewards are worth it. Like anything, having a game plan will help you get started and make the job a little easier. Therefore I will show you the steps I follow when collecting and charting the hatches on a new stillwater. [Make certain that collecting is allowed in your state]
First, select 1 or 2 lakes or ponds that you wish to chart and set up a schedule of when you will collect. I suggest doing so every two to three weeks minimum, from ice-out to freeze-up. Keep good records on the weather, water temps, water levels & condition of weed growth each and every time you collect. Also, draw a map of the lake and record areas where you collected the various food forms. I use the BCS Borger Color Guide when collecting the food forms. This will give me a true picture of the size and color of the forms collected. Then I will identify the food form.
COLLECTION EQUIPMENT
Notebook, pencils, Borger BCS Color Guide & data pads, small mesh insect net, long handled insect net (for collecting flying adults), large insect seine, ethyl rubbing alcohol (for preserving), small bottles, self adhesive labels, and a roll of clear tape. Each type or species collected should be labeled as to location and date.