Fishing Articles
Fluvial Processes
Active processes of river formation and evolution.
River alterations dictate the best and worst times to fish.
Timothy Kusherets
This river, the night before, had zero visibility
running thousands of Cubic Feet per Second (CFS) higher blowing out
the river; however, the grade of the river and the volume of water receded
fast enough that it was possible to anticipate how long it would take
for it to clear up making the system fishable. Note how easily the body
movements of this fish stir up silt from the riverbed.
Fluvial Processes means all actions associated with the birth,
longevity, and maintenance of any river or stream through natural interactions
of water, gradient, speed, suspended particulate matter, and bed-loads
which are all carried by currents. Runoff, saturation, sediment, turbidity,
and scouring are forms of fluvial processes that directly affect freshwater
fishing. Rivers could not exist without fluvial processes and become
important elements to anglers wanting to fish either clear or turbid
systems. Glacially fed systems are very different in behavior and formation
from that of runoff-fed systems. These processes have minute partical
sediment loads that vary by size, frequency, and density. How large
a sediment load is dictates how much oxygen is available in any stretch
of water. Oxygen depletion will keep many species of fish off the bite,
sometimes killing them and is directly correlated to suspended silt
where visibility is zero.
These are just a few reasons to factor in what moves and shakes a river.
Every river has some form of sediment load that moves down river. In
most cases, provided there is substantial movement, all rivers are capable
of providing a livable habitat despite sediment accumulation, dispersion,
and suspended load where the water looks traditionally “stained”.
These formed habitats are varied and cater to specific needs of fish
making fluvial processes an important aspect of drift fishing techniques
for anglers to figure out where to fish, what to fish, and how to fish.
Here a river has swollen far beyond its banks but it was still
possible to hook into a couple of nice looking steelhead.
The visibility of this river was zero inches with particulate matter
completely coloring the water muddy brown. The large volume of floodwater
will literally "scour" the riverbed cleaning it of algae,
debris, and accumulated bedload silt. How a river floods, recedes,
and stabilizes are all fluvial processes that determine oxygen levels,
clarity, depth, current speed, and width; how and why these elements
work dictate fishing season, species of holding fish, and how to fish
each reach of water.
© Timothy Kusherets 2008/09 Copyrighted
|
