The streams that flow from Boulder Mountain near the town of Boulder hold several species of wild trout. Rainbows like the fine example at right inhabit the mid elevations of these streams. Most of the wild rainbows that you can expect to catch on small streams like these are going to be in the ten to twelve inch range with the occasional sixteen or eighteen incher. Depending upon your skill with a flyrod and your ability to spot bigger trout holding, you can certainly manipulate the size ratio towards the bigger fish.
Wild brown trout like this beauty are found in the lower to mid elevations along these streams. Like the rainbows. wild browns are numerous. Some days the catch seems to be mostly browns. Other days it's more rainbows. The browns are running similar in size to the rainbows on average. But when you get a real good brown in one of the streams, it will sometimes go twenty inches! Usually the larger browns will take cover near the undercut banks. At the first sign of your approach they will dart under the bank. But a well placed streamer will often lure them out for a strike.
Cutthroat trout are plentiful in many of the lakes and beaver ponds at the higher elevations of Boulder Mountain. The example at right is a Yellowstone cutthroat trout. These beautiful trout are known to take a fly. Flyfishers hook these cutthroats easily with dryflies and nymphs. They will cruise the grassy edges and are within easy reach of any good flycaster. They are suckers for the dryflies and when hooked will put up quite a fight. The Yellowstone cutthroat will grow to great size in these lakes and fish over five pounds are fairly common.
