Here we have a condition that is simplicity itself, yet it has puzzled and vexed many anglers whose conservative ideas never take a turn, and who reason the matter trying to solve a problem that is as plain as plain can be. It is the first and most important thing for the angler to learn that the fish in each body of water (large pond or lake), whether rainbows, brown or brook trout, or even a combination of them, almost invariably feed upon one species of fish or other food. Sometimes it happens to be young bullheads, of which parts of the lake are a living mass. In other lakes I have found the bed to be covered with young sunfish, from less than a quarter of an inch to two inches long. In other lakes, where the bed is in most part covered with aquatic growth, at certain seasons this is alive with fresh-water shrimps, creepers, beetles, and insects.
In some lakes (large or small) where food is so thick as to be consumed without effort, trout do not rise to flies at the surface; also they do not usually display any active resistance when captured on rod and line, whatever bait may be employed. The right bait to use must be found out by opening the stomach to see what it contains. Anglers have found that in almost every instance the worm, either large or small, has heretofore been the only successful bait to capture specimens for investigation. At the same time, the worm is not always a safe bait, and I am sure that a live bullhead or sunfish, if it can be procured, is bound to be more effective to get those trout, or an artificial imitation made to act in the water like that, or other natural food. It is far more difficult to attain success in bottom fishing than at the surface of lake, where food is not visible and trout congregate together in certain parts which are very difficult to determine. We can only spot them by frequent tests of different food. The reason why one species of fish food is most abundant is because the food-supply they exist upon is very plentiful, except in case of cannibalism, as in bullheads or catfish. After a time, both trout and bass by feeding bring down overabundance to reasonable limits. The young of perch, dace or fall-fish, suckers, and many species of minnows are preyed upon according to their numbers, and it is natural that fish choose to abide near at hand to get them.
One lake I have often fished contains plenty of large brook-trout which feed exclusively on young sunfish. Local anglers have captured them only on the bottom with worms, and have never been known to take artificial flies or even the natural insects which are at times quite plentiful at the surface. After the first of May a host of large-size sunfish take all the worm baits and no trout are caught during the entire season. As yet I have had no chance to test other baits than worm; when I do, the result will no doubt be favorable. These trout have no opportunity to get worms. It is the kick and liveliness which is so attractive to them, and any other active bait (not attractive to sunfish) would, I am sure, suffice just as well. From the stomach of one trout I have taken as many as twelve young sunfish half an inch long, while neither insects nor other food was found in any of the trout captured in this lake on many different occasions. Fy-casting, dry or wet, was to everybody a vain effort. This condition is typical of many lakes in localities wide apart, except that the fish food varies, yet in each individual instance anglers, after trying flies and worms, always give the matter up in disgust or despair. I repeatedly get plaintive letters from anglers, even from Canada, who say, "I know lots of fish are in this lake, but nobody can find a bait to capture them and they won't touch flies." The reply would be quite easy if I knew the fish food contained in the lake. The only proper way to go about solving such a difficulty is simply to take tests of the food-supply, either by observation, by the use of live bait known to be attractive, or by artificial imitations of game-fish food, tried one after the other till success is won.
Another difficulty arises sometimes. Some lakes, indeed most lakes, have a disturbance that is generally known as "purging," when the water has a muddy, unclean appearance, filled with tiny particles of colored decayed matter. On those occasions, which happen once or several times each season, the anglers say fish are off feed; and they never try. For generations they have been given to understand that it is useless fishing a purging lake, simply because their limit of enticing baits begins and ends with worm or fly. I hope these chapters will furnish many good remedies worth trying. In other lakes I have found that trout live entirely on bottom creepers before they develop into the adult insect state. These creepers are so numerous in certain parts of the lake bottom, that when in an advanced state of growth, finding all food gone, they devour each other. Various species of trout and landlocked salmon at times find a glut of bottom food so numerous that they can feed to suffocation without effort, especially at certain periods when a change from the creeper to winged insect occurs. Lake Champlain is a case in point. Enormous and vast are the clouds of green drakes (known in England as the Mayfly, but larger in size) flying over the water every season about the first week in June. Here is the important point: the bass for which the lake is famed have never been known to feed on the glut of surface insects. Doubtless they are gorged with a full share of the creepers taken at the bed of the lake. The artificial nymph-creeper of this insect should prove a good bottom lure on such occasions for bass. Surely at such times, a good supply of the creepers could be removed to those waters where they are not common, in order to assist nature in a more liberal supply more evenly distributed. This chapter is intended to convey the truth that if trout and bass in lakes won't take flies, it is entirely convincing the fly as a lure is not perfect, and something else can be made to take its place that is perfect; at least, we can make the effort, and not go home in despair because bass refuse a "plug" or worm. The common saying, "Bass or trout are off feed," is a much mistaken notion. Both these fish are feeding, we may be sure, and if we wish to get them, we must attach to the hook a lure that is like the food they are taking. How much better, then, if our lure correctly imitates their food, in appearance as well as in action, the chances are to succeed, than if we offer them a bait they don't know or don't want. Several of the new bottom-creeper lures to my thinking are just the thing to solve this vexing problem; if they do not, a small minnow,. cricket, or grasshopper can be offered in succession till the fish do respond. Heretofore, outside of live bait nothing was available but plugs, worms, and flies. The angler who does more learning "how' and "why" will find his time vastly more interesting than sitting waiting till fish are in the "humor to bite." I feel certain that bass, and trout in particular, are always in the humor, unless they are overgorged.