What makes a good trout stream

As a stream moves from the mountains into the foothills, several significant things happen. Its gradient declines, which increases the amount of suitable trout habitat. It enters a friendlier environment at a lower elevation, which provides a longer growing season and reduces the likelihood of freezing to the bottom. A foothill creek flows through forest or farmland, and its streambed is composed of gravel, silt and soil instead of just rock as in its headwaters.

Decaying leaves and plant material, animal waste and minerals wash in with the spring rains, providing nutrients to stimulate green plant growth. The stream also may flow through geological formations that leach calcium and other minerals into the water. So trout fishers in search of Nirvana in Alberta find it in the streams of the western foothills, near towns like Pincher Creek or Sundre or Grande Cache, where aspens and willows mingle with evergreens to provide shade, cover and nutrients to the trout.

Knowledgeable fly fishers are drawn to these gentle and aromatic valleys, knowing that finding trout begins with finding trout habitat. All rights reserved. Home Books. Show Comments.

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These naturally vegetated areas also prevent erosion, filter pollutants, and provide shelter and food for fish and other aquatic organisms. Protecting and enhancing forested riparian areas is critical to maintaining the conditions trout require to thrive.

The future effects of climate change will heighten this need. Unaltered rivers and streams moderate water flow through natural hydrology and fish can adjust to changing conditions. Man-made changes in water flow can limit wild trout production by increasing the magnitude and duration of extreme conditions, such as floods or drought. For example, hydroelectric operations and water withdrawals can impact trout by manipulating the natural hydrology.

The Battenkill flows through a valley flanked by insoluble granite and gneiss to the east and marble bedrock to the west. Its pH fluctuates from around 5 below tributaries or springs entering from the east to more than 7 downstream of tributaries entering from the west. Trout in the brooks on the eastern slope will take a big dry fly all day long, regardless of the insects hatching or the time of day, but if you hop over to the other side of the valley, the trout often ignore a blind-fished dry fly.

You have to use smaller flies that look more like the insects that are hatching during the current week, and the trout seem to have periods of lockjaw when no fly will work. The trout in the western tribs are also bigger and fatter. Rocks composed mainly of silica contribute nothing to the productivity of a trout stream because they release no carbonates into the water. Silica rocks in streams can be recognized by their smooth, rounded shapes and crystalline structure.

The ones you commonly see making up the beds of unproductive trout streams are gneiss, sandstone, quartzite, and various forms of granite. Seldom do I predict the richness of a trout stream solely by staring at the rocks.

For example, the color of the water can often be a dead giveaway to its richness. The tea-colored water so common in the north country indicates an infertile stream, where trout will be small, slow-growing, and eager to take almost any fly pattern.

In the limestone belt of Pennsylvania many of the streams have a gray or white tint due to undissolved calcium carbonate, and the trout are well-fed, pickier about what nymph they take, and less inclined to come to the surface for a blind-fished dry fly.

Water with no apparent color is not much of a help — it can indicate either a stream where all the brownish humic acid has been neutralized by carbonates, or, as in many high-altitude streams in the Rocky Mountains, water that has few dissolved minerals of any kind. Crystal-clear water can indicate purity, but absolutely pure water is less productive than water that contains some dissolved nutrients.

This is a hard pill for most of us to swallow, but water polluted with human or animal waste is always more productive than pristine water. Above the city of Calgary the Bow is relatively infertile and can be easily blind-fished. Below the city, where the waste of over a million people enters the river, it is fertile beyond comparison in that part of the country, and the trout show the pickiness, reluctance to feed at certain parts of the day, and hesitance to come to the surface that are common among well-fed fish.

Studies in Michigan and Pennsylvania have shown that removing domestic sewage can dramatically reduce the productivity of a trout stream, while adding it can make an infertile stream rich.

The same goes for water that flows through agricultural land. Sewage and agricultural fertilizer are rich in phosphates and nitrates, and the lack of these nutrients often limits plant growth in streams, so when you add them to a stream you get the same effect as when you sprinkle on your sweet corn in the spring. A study in Wisconsin found that runoff from one hectare of agricultural land puts 7.

This beneficial effect walks a fine line because pollutants can also increase the biological oxygen demand of a stream, especially in hot weather, and too much organic material without cool water and a lot of riffled water can suffocate trout. Weeds in the water always indicate higher productivity, and as a result more invertebrates for trout to feed on.

Watercress and stonewort thrive in alkaline environments rich in carbonates, and long, thin, bright green strands of filamentous algae tell you either that the water is rich in carbonates or that sewage or agricultural effluent is present.

The water will be richer below town, as it is in the Bow, but you should be aware that not all rivers have the head of cool water to compensate for the increased oxygen demand during the summer.

You thought it was bad enough that normal people ridiculed you when you walked around in trout streams with a butterfly net. If the local water supply contains a high concentration of carbonates, chances are the nearest trout stream does, too.

Tailwaters like the South Platte can be as rich or richer than spring creeks, and the banks usually show stability, with no sign of frequent flooding. Tailwaters Are Usually Rich, Too I lied when I told you that spring creeks are the richest trout environments in the world. They are the richest natural trout environments.

All of these rivers famous for their imposing trout and plentiful hatches are made rich by the still waters above them. Dams, if they release water from the bottom of the reservoir above them, as most of the famous ones do, stabilize both flow and temperature by being miserly with spring runoff and doling it out throughout the summer. Floods are reduced, temperature extremes are moderated, and growth is easier. Nutrients are concentrated in the impoundments behind dams.

Trout also benefit in tailwaters because plankton is washed directly into the rivers and eaten by insects and crustaceans. You may miss the right part of the riffle and pick up rocks that are barren just by chance. You might be looking late in the season, when most of the larger insects have hatched and their offspring are too tiny to be noticed. Also these animals usually live in deeper water than you want to reach your arm into.

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Angling for Surprise. Fly fishing. By George Athanasakes. It takes a multi-disciplinary team — and lots of research on trout life cycles — to restore a stream to sustain new life. There is nothing like trout fishing along a pristine stream. Now, imagine — as an avid fisherman — your team is asked to create a pristine trout stream at a site very close to home with all the extras you see on those great trout streams from afar.

Hatchery Creek is unique because the source flow is cooled by the depths of Lake Cumberland and flows through the Wolf Creek Dam National Trout Hatchery near Jamestown, Kentucky, where rainbow, brook, and brown trout are hatched and raised.

Prior to initiating our work, the stream flowed feet through the most heavily-fished stream in Kentucky, then down an eroding ravine into the Cumberland River just downstream of the Wolf Creek Dam.

Because many of our streams in Kentucky are too warm, self-sustaining trout streams are very scarce. Although the water just below Lake Cumberland dam is cold enough to support trout, water level fluctuations from the operation of the dam prevent successful spawning.

First, under normal conditions the channel flowed at 30 cubic feet per second, which was very high compared to the contributing drainage area of the watershed.