A Systematic Approach To Success

As river water meanders downhill, it flows over bottoms of varying hardness. Riffles form over hard-bottomed areas and are shallower, because current doesn’t wash away hard bottom. Riffles form natural dams that obstruct moving water. A pool of water builds at the head of a riffle and eventually flows over it, quickening over the constricted area. In most small rivers in farm country, riffles rarely run for more than 30 or 40 feet.

The force of water flowing over and down a riffle scours the softer substrate at its bottom, forming a hole or a wider and deeper river section. Depth of a hole varies according to the steepness of the riffle, subsequent current patterns, and the size of the river. In a small stream, a typical hole might be 30 feet long, 20 feet wide, and about 4 feet deep. The biggest and deepest holes might be only twice those dimensions.

Holes gradually become shallower at their downstream end as suspended materials sink when the current slows. The tail end of a hole becomes a run, which is a river flat, an area with minimal change in depth. The bottom usually is sand and silt with some gravel, plus plenty of debris like wood and brush. And, you guessed it, at some point the river flat winds and finds its way to another hard-bottomed area, a riffle forms, and begins another series of riffle, hole, run.

Flooding helps to distribute timber, brush, and other debris throughout a river. Fallen timber most likely occurs in conjunction with a river hole because of the increased scouring action of current there. Once a tree falls and is held by its roots to the bank, it becomes a prime obstacle gathering floating debris. The biggest snags form in conjunction with riverbend holes. The most extensive of these become prime holding areas for catfish, usually the best areas in a river.

Free-floating timber and brush also settle easily at the margins of a hole, or at least at its tail end, as the current slows and a run forms. Boulders that serve as cover also (again because of the scouring action of current) more likely occur in conjunction with a hole. Cover on river flats (runs) is, by comparison, haphazardly placed and, of course, rests in shallower water and therefore tends to draw smaller catfish. Cover in conjunction with a riffle usually doesn’t draw catfish unless they’re feeding and have moved up from the hole.

Holes, then, are the primary home (or holding area) for catfish most of the time. Catfish tend to spend a major portion of their time holding in or near the cover elements in and around holes. When feeding actively, they often move upcurrent into and through riffle areas. At times, they also spread downriver into runs. This is the essence of understanding catfish location in rivers.