On trout lakes, the action is in the cruising lanes, where most of the feeding goes on
Someone once said that the only difference between trout in lakes and trout in rivers is that in rivers the water moves and the fish stand still, whereas in lakes the water stands still and the fish move.
Of course fish don’t always do what they’re supposed to, but it’s true: A trout feeding in moving water will usually lie in or just to the edge of a current that carries food to it. Put the same fish in still water and it’ll have to hunt up its food by moving around.
In some rare situations where you have uniform bottom structure and no insect hatches going on, you’ll find loose pods of trout cruising lazily all the way around a small lake or pond like hamsters on a treadmill, only slower. But more often the fish will concentrate in one part of a lake or another.
The key to any body of still water is its littoral zone: the part of the lake that’s shallow enough for sunlight to penetrate to the bottom so aquatic vegetation can take hold. Insect nymphs and crustaceans eat the weeds and trout eat the bugs. This is where most of the transactions in the day-to-day food chain take place.
How extensive the littoral zone is depends on the composition of the bottom, the clarity of the water and the shape of the lake bed. All things being equal, a steep-sided, rocky-bottomed mountain reservoir will have a narrow, sparse littoral zone, while a shallow lake with a silty bottom will have a wide, rich one.
When I’m fishing an unfamiliar lake, I always try to locate the weedy spots and fish there first because that’s usually where most of the feeding goes on. It’s not foolproof, but it works often enough to keep me doing it.
When that doesn’t work, I look for other obvious spots: dropoff shelves, points of land that extend out into the lake as shallow bars, steep banks with overhanging trees or tall weeds, and of course the inlets and outlets of streams. Even trout living in lakes have an inborn weakness for current.
On the Rise
If you can see trout rising, two-thirds of the mystery is solved: You know where the fish are and you know they’re feeding on something on or near the surface. The trick here is to put your fly ahead of them. Remember they’re cruising, so by the time a fish has eaten a bug–leaving a ring on the surface–it has already moved on, looking for the next bite of food.
If there are lots of insects on the water and fish are feeding well, you’ll see gulpers: trout rising steadily in a more or less straight line. Here you simply lead the fish with your cast the way you’d lead a duck with a shotgun. More often you’ll see the scattered rises of several fish, and if there are lots of them in a small area you can usually get strikes by just “casting in amongst ’em,” as a friend of mine says. But I like to try to pick a fish, preferably a big one.
If you watch rises closely you can sometimes tell the size of the fish and which way it’s going, especially if it breaks the surface with its back or tail. How far you cast ahead of a rising trout depends on how fast it’s traveling, and sometimes you can tell that from the rise form, too. Trout cruising slowly usually make slow rolls or lazy-looking boils on the surface, whereas fish that are charging around make splashy rises.
When I’m trying to lead a fish that’s moving, I always figure too far is better than not far enough because the fish can still come up on the fly. If you cast short, it’s either already past the fly or your cast will land too close and spook it.
If I can’t tell which way a cruising fish is going I just take my best guess and cast to one side or the other of it. After all, the one sure way to put a fly where there’s no fish is to cast directly to the rise.
If there are no rising trout, you’ll just have to fish in a likely looking area. It’s always tempting to wade in up to your armpits and cast as far as you can toward the middle of the lake, but that can be a mistake. If a trout lake is more or less undisturbed–that is, if there aren’t a dozen other fishermen already wading around in it–the fish will often cruise surprisingly close to shore, especially along steep drops and weedy or shaded banks.
Sometimes the best tactic is to cast back toward a good-looking bank from a boat or float tube. If you can’t manage that, try standing several yards back from the water and casting to the shallows, or if the bank is weedy or brushy, get in the water and cast parallel to the shore.
Trout in lakes often become partial to a specific insect, especially during a heavy hatch, but if you’re fishing blind or casting to cruising trout that don’t seem to be feeding heavily, there are some well-worn choices of fly pattern.
Many lakes hold leeches, which trout usually feed on opportunistically. A Woolly Bugger, in olive, black or dark brown, should do the trick.
Streamer flies can be effective in waters known to have populations of forage fish. It’s best to stick with a standard pattern, like a Muddler Minnow, and carry a variety of sizes.
Thin-bodied damsel-fly nymphs are a common food of lake trout. There are specific damsel nymph patterns available, and many standard mayfly nymph patterns, in olive and brown, will also work.
Lakes with good populations of freshwater shrimp–also known as scuds–are notorious for growing big trout. These crustaceans vary widely in size and trout sometimes get particular about them, so it’s a good idea to have a few in, say, hook sizes 18, 14 and 10. The simpler patterns are often the best. The most common colors are olive and tan.