Text Box: Stream Tender Magazine

“ December 2013 Issue”

 

“ Willows Along the Water’s Edge “

    Willows and trees along the shoreline and riparian zone of flowing streams contribute to a healthy natural environment, and they play an integral role in the biodiversity of our waterways. They create habitat for wildlife, maintain stability in stream banks and keep the water temperatures cool enough to support life.

    With my attentions directed towards the enhancement of a stream’s fishery and the habitat that the fish depend on, I have learned a lot about the importance of these plants. Over the past 30 or so years, I have had the opportunity to study the benefits of willows and trees to both fish and the invertebrates that fish  feed on.

    It has become quite apparent to me that a healthy riparian zone, with good willow and tree growth, creates a complex web of life that is full of new discoveries. There is always something new to learn, for the keen observer or those that work in the environment along streams.

    As a fly fisherman and fisheries researcher, I have learn how trout relate

to different types of in-stream habitats. I know that submerged and overhanging woody debris provides important habitat to trout,, especially juvenile fish! Depending on the life stage or  year class of young trout, they will utilize different types of submerged and overhead willow and tree cover.

    Over the years, I have conducted a number of juvenile trout trapping programs on a few different streams. It was during these operations that I really began to learn more about the importance of various woody debris habitats.

    Shallow lateral margin habitats along the stream banks, with plenty of twigs and branches, were the best place to find young of the year (YOY) trout. While submerged branches and trunks over moderate riffles and medium depth runs,  provided great habitat for trout that were large enough to occupy these areas of the shoreline.

    When I was fly fishing, I found that woody debris in or over deeper water would usual provide habitat for the larger trout. Especially brown and brook trout.

    Apart from providing fish with decent habitat, willows and trees also benefit a stream natural process of maintaining narrow constricted flows, with clean substrate bottoms. I have observed areas of partially submerged willow plants, that acted as debris catchers for leaves, twigs, branches, grasses, weeds and silt. Over time, this debris becomes part of the stream bank.

    The root systems of willows and trees that grow along the water’s edge provide great stability to the stream banks. These areas along the water also have some really nice undercuts that trout will utilize.

    Something that is often overlooked, when it comes to submerged wood, is how this organic biomass benefits invertebrates in streams. Even leaves from willows and trees are feed upon by a wide variety of invertebrates. Lots of wood in the water increases the amount of bio-mass which enriches a trout stream.

    There is a lot to think about when it comes to willows along the water’s edge!

The German Brown Trout  -  A Cherished Sport Fish!

Above: The willow tree shown in this photo has its base growing right along the water’s edge. The plant provides shade and overhead cover for trout. Some of its broken off branches, just downstream, are submerged and are providing good habitat for smaller trout.

Above: The willow branches on this lateral margin habitat are collecting silt and debris, such as leaves. Over time, this will spot will grow into the stream bank. In the meantime, it will provide great habitat for “ young of the year trout “. This is vital habitat for small fish!

    The first variety of brown trout to be introduced in Alberta waters, was the Scottish Loch Leven strain. Later on in the 1930’s, the more common and popular German brown trout arrived in our province. Today, the German strain is the common catch on all of our area brown trout streams.

    I suspect that the preference for  the German brown trout came about  due to their more attractive coloring and also German brown trout are a fluvial strain of trout. This means that they do far better at living in streams that they do in lakes.

    The color difference between the two is that German brown trout have red spots and Loch Leven’s don’t! Also, Loch Leven’s are a lake strain of trout, thus the name Loch.

    One of the primary reasons that brown trout are best suited to many of our foothill streams, is that they are fall spawning trout. They lay their eggs in the fall, when the water quality is more conducive to a successful incubation.

    With the impacts of agriculture andcenturies. At least this is my theory on the matter!

 development, many foothill streams experience dirty water conditions during spring run-off, when cutthroat trout and rainbow trout spawn. Which impacts the incubating trout eggs, by smothering them with silt.

    Also, brown trout are very tough fish! They had to be, in their native European home land, where angling pressure has been very high for many

    You will find that brown trout are abundant, on many foothill streams north of the Bow River. Streams such as the Dogpound, Fallentimber, Little Red and so on. Hopefully they will also be more abundant in the Bighill Creek!

    The local brown trout streams are known to produce some very large trout on occasion. They can grow up to 5 or 6 pounds and surprise even the most active and experienced angler.

    When they spawn in the fall, they fan a rather large nest or redd in the gravel bottom of a streambed, where there is adequate velocity of depth for the eggs to incubate successfully. These redds can be pretty large in size, averaging approximately 12” X 24” , and larger.

Above: This is an average brown trout redd. You can see a mound of clean gravel and at the top end of the redd, is a depression. The small depression is where the fish fanned gravel over the eggs to finish off the spawning event. The clean gravel mound makes the redds easily identifiable when you know what to look for and when.

The mound of clean gravel

The

Depression

Left Photo:

    Brown trout such as this German brown, are common on many brown trout streams, to the north of the Bow River, in Cochrane. I especially enjoy catching brilliantly dressed brown trout like the one in this photo. Its color is accentuated by a golden yellow hue, that is typical in the tainted color streams of the foothills.

    The Dogpound Creek is known to produce some real monsters. I know of a few 9 pound fish that have been captured, one by electro fishing and the other on a fishing rod. The largest fish that I have heard of, was captured by Fish & Wildlife electro fishers, and it topped the scales at 12 pounds. This fish was accurately weighed and measured during the study program, so it is no fish tale!

    The larger brown trout are often caught by fly fishers that used streamer patterns. A large part of a mature brown trout’s diet consists of minnows and other large invertebrates such as leeches, dragon flies, grasshoppers, stoneflies and so on. Like other trout species, they don’t like to expend too much energy while feeding, so the bigger the meal, the better!

 

    “ Just the mere beauty of these trout should inspire us to take care of the environment in which they live! I know that it helps to motivate me! ”