Lakes rarely have the necessary spawning habitat to produce self-sustaining rainbow populations, so they need periodic restocking of fry to repopulate. If the lake has a gravel-bottom inlet or outlet stream, then mountain rainbows will do as Mother Nature intended.

Golden trout are rare mountain treats for backpacking anglers, especially the father north you go. Its scientific name, O. mykiss aguabonita, speaks of beauty. Goldens sparkle when the sunlight dances off their dark green back, crimson lateral line, gold body and white-tipped fins. Natives of the Kern Plateau of the Sierra Nevada, goldens have been successfully stocked in cold, clear mountain lakes in places like Oregon's Eagle Cap Wilderness and Washington's Alpine Lakes Wilderness.

Most people assume that mountain lakes and streams hold only small fish. Don't believe it. While not every lake or stream gives up a lunker on every cast, most will grow big fish if they're allowed to mature. The Sierra and Cascades produce West Slope cutthroat, rainbows and eastern brooks over 6 pounds. The Oregon golden trout record approaches 8 pounds, while the 11-pound world record was caught in Wyoming's Wind River Range.

LEAVE NO TRACE
Fishing in pristine mountain environments is good for the soul. But protecting these fragile places requires special etiquette to minimize your impact.

With a few simple guidelines, pristine places can remain pristine and a joy to visit, time after time:
• All users must protect fragile alpine meadows and shorelines.
• Avoid beating a trail around a lake.
• Don't camp in meadows or within 200 feet of a lake.
• If you bring stock, tether them away from water sources and clean up after them.
• Check with the U.S. Forest Service and National Park Service for brochures and other information detailing these and other simple steps for no-trace hiking and camping.

Alpine fish populations are often fragile as well. Consider practicing catch-and-release fishing, perhaps keeping just enough smaller fish for that evening's meal.

If you hook a lunker, land it as quickly as possible, leave it in the water while you snap a few quick photos, then release it after ensuring that it can maintain its equilibrium. Any lake with more than one size-class of fish generally indicates a self-sustaining population. Releasing the biggest fish contributes to the gene pool. Exceptions to the release rule are those lakes, usually populated by brook trout, in which you catch skinny fish with big heads. That's a sign of stunted growth due to overpopulation. Taking those fish will help adjust their population to match the available food.