I fish for larger, more difficult quarry when the opportunity presents itself. I'm not unaware of the appeal of race-horse rainbows in broad tail- water riffles, of stubborn brown trout in weedy spring creeks, impossible steelhead in fog-shrouded western rivers or mythological Atlantic salmon holding in classic, gin-clear pools. But looking back, I know now that Salvelinus fontinalis was the only trout I ever needed. An entry-level trout for many anglers—a hungry, wild fish not difficult to catch in mountain streams or in northern ponds—I never needed any other level of angling than the brook trout fishing I have enjoyed over the years from Georgia to Maine.

All those days coalesce into a single scene: A mile of mountain stream sheathed in granite and shaded by eastern hemlock. A stiff gradient of white cascades between promising, sea-green pools. Impossible log jams followed by easy reaches open to long casts. Boulders so gently sculpted they seem animate. Great trees casting a green shade under a cathedral-like canopy. An infinite loop of noise-canceling stream rush playing all day, making time stand still. Waterthrush and woodpeckers, towhees and grouse drumming, sudden deer stare at streamside or a black bear grumbling around. And trout, wild brook trout—holding in the light, hiding in the shadows, receding under the tantalizing spread of the ring of a rise.

The angling is good enough, a fair reward for the effort of being there.

This is pure fishing—fishing without an audience, fishing without the pleas- ant distraction of camaraderie, fishing that doesn’t require tackle any better than tackle was 100 or 200 years ago. The trout are not particularly selective but there is always one good, difficult boss trout in each pool or run—the fish to catch first while the others scatter. And there may be one outsized trophy in the mile, a 12 or 14-inch beauty with a broad head and some heft to it when you hold the fat arc of it just out of the water to remove the fly, the wild brood fish of the stream, lithe and solid as an axe handle. If you miss this fish, you’ve missed the grail for the day, however pleasurable the quest and however many 8 and 10-inchers you counted coup on. To prove your mettle as a brook trout angler, you fish every spot as if that prize was hidden everywhere. The genius of such a day is that you will get your fill of fishing but not your fill of the river and the mountains and the woods, of birds and critters, sounds and scents, of weather and the edgy gleam of time passing.

The brook trout, as I think of it now, is the naturalist’s trout, a fish that first rivets our attention on one thing—the trout we must catch to prove ourselves anglers on stream—but then broadens our attention, which more demanding fish tend not to do. (Cutthroat probably have the same effect on those who start their angling lives in the American West.) Brook trout have introduced many anglers not just to fishing but to nature. They teach us to engage nature with energy, enthusiasm, intelligence and respect. They teach us not only to observe but to see. They teach us to extend our curiosity and our desire for knowledge from one thing to another and inspire a permanent desire not just to understand fish and rivers, but to know the life of woods and mountains.

This has long been the case. In a fine essay, “Fly-Fishing Alone,” in his 1864 classic, American Angler’s Book, Thaddeus Norris recounts how easily the angler of wild brook trout begins to become a naturalist of his or her surroundings. “It was only just now the red squirrel came down the limb of that birch....The mink, as he snuffed the fish-tainted air from my old creel, came out from his hole amongst the rocks and ran along within a few feet of me....I recollect once in the dim twilight of evening, a doe with her fawns came down to the stream to drink....A moment since the noisy king-fisher poised himself on the dead branch of the hemlock....The little warbler sang in the alders close by my old felt hat.”

During a long day on stream, our interest in brook trout teaches us to admire all forms of life—all bios—for their own sake and not just for our own sentimental pleasure or psychological comfort. Many of us have learned on stream, better perhaps than we did in the classroom, to feel the subtle complexity of ecology, to begin to understand in visceral terms what nature is, perhaps a more pressing question for us now than in Norris’ time. Brook trout are, like all spe- cies, a survival from the deep past,

one expression of natural selection and of evolution—a form of life that has succeeded since the Oligocene, adapting for 100 million years to the pressures of natural selection. And everything we discover in a brook trout watershed—the caddis in the air, the alder along the stream, the oak and hickory on the ridge, that kingfisher still harassing the stream— is a school for understanding both the deep poetics and the deep ecology of watersheds.

Brook trout teach us to keep going—to fish the next pool, to explore the next stretch of river—and they teach us to sit still, to enjoy the life around us wherever we stop. They lead us to want to know the names of things and have taught us more Latin than we thought we would ever know. If they were more difficult to catch, they would not leave us as much time to grow in awareness or help our angling evolve beyond being merely recreation or sport. If you keep coming back to brook trout and the superb place where they still thrive, you are coming back for more than fishing.

Chris Camuto is the author of four books, including A Fly Fisherman’s Blue Ridge, in many respects an homage to brook trout, which is enjoying its 20th year in print. He lives on Wolftree Farm in central Pennsylvania and teaches at Bucknell University.