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Understanding Flash And Its Limitations

Friday, September 09, 2011
by Dr. Keith Jones

Photo: Berkley
According to Dr. Jones, flash might not necessarily suggest a wounded prey item.

Bass are consummate visual hunters. They use a variety of visual factors to locate and assess lures, including size, shape, color, flash and action. Moreover, they can assess all of these factors simultaneously from considerable distance.

Bass that feed solely on a single source, for example shad or crayfish, appear to develop complex visual search images that they use to evaluate potential food. With enough feeding experience, a visual search image becomes the standard against which the bass compares the targets it encounters.

The likelihood that a lure will be attacked depends on how closely it matches the visual search image. In extreme cases, a bass may come to ignore anything that fails to match that image – hence the wisdom in "matching the hatch."

It doesn't matter whether the visual lure is natural or unnatural, real or artificial. These terms hold absolutely no meaning for bass. What does matter is how well the lure fulfills the bass' visual predatory expectations.

In addition to color, which we covered in a previous article, bass may be able to differentiate prey based on their specific flash patterns. There's little doubt that bass use bait flash as a predatory cue.

In clear water, the telltale flashes of schooling baitfish can be seen from some distance, especially on sunny days. Signature flash patterns could help the bass identify the species of baitfish, size of the school, average size of its members, their general activity level and whether the school is feeding or dormant.

Anglers have long played on the susceptibility of bass to bait flash. Metallic spoons, spinners and chromed crank- baits, to name only a few examples, all use flash as an attractant. Most anglers assume that bass mistake these baits for natural preyfish, but this need not be the case.

Indeed, it's difficult to believe that a predator with a visual system as sophisticated as that of the bass would be unable to distinguish flashes of a baitfish from the rotating blade of a spinnerbait. Flashy baits may instead simply play on the fish’s instincts. If this is the case, bass do not have to be taught to associate bright silvery flashes with schools of baitfish.

An inborn attraction to flash would make bass approach anything that flashed, including baitfish, and stimulating natural flash patterns wouldn't necessarily be the optimal bass-catching strategy. Other flash patterns might play on their instincts even better. To use flash, we must understand how the bass perceives it.

Indeed, it's difficult to believe that a predator with a visual system as sophisticated as that of the bass would be unable to distinguish flashes of a baitfish from the rotating blade of a spinnerbait.

Flash, as we know, is a sudden increase in light intensity. Lures with a flat, highly reflective surface produce the best flashes, but only when the reflective surface aims the light towards the fish's eye. When viewed from any other direction, the eye doesn't detect the flash.

The more a lure tends to turn, the greater its flash potential. Flat-sided crankbaits that twist or roll through wide arcs have a decidedly larger flash field than others. Lures with sharp curves, on the other hand, like chrome fat-bodied crankbaits, no matter how reflective, produce only weak flashes or no flash at all. In bright sunlight, these lures have "hot spots" that roll across the surface as they rotate. The hot spots move, but the reflection doesn't flash on and off. These lures may be bright, but they're not flashy.

Adding flash to your presentation has positive points. Flash enhances lure detectability. Some flash patterns may accurately simulate baitfish, yet bass may find other patterns inherently more attractive. Thus like color, flash has its limitations.

Dr. Keith "Doc" Jones is director of research at the Berkley Fish Research Center in Spirit Lake, Iowa. His book "Knowing Bass, The Scientific Approach to Catching More Fish" is available at Amazon.com, Barnes and Noble, and other booksellers.

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