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Spring 2020
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The movement of prey, or lures, along with their various rattles, hooks, etc. put off sound waves. Those waves are felt by the lateral line, not heard by the bass. The lateral line is sensitive to very slight motions. The lateral line is a series of pores or canals in a row of scales that stretch from just behind the gill plate to nearly the tail in a bass.
HOW THE LATERAL LINE WORKS
These canals contain a series of cells that have hair-like extensions surrounded by a gelatinous substance, together called neuromasts. Vibrations from surrounding water on one or more of these groups of cells send a message to the brain.
The central lateral line neurons obtain the information necessary to determine both the position and the vibration direction of an object.
FREQUENCY
So then…louder or lower frequency is better right?
Well, we need to remember that fish are highly tuned to the common sounds of natural water disturbances. A common source of natural water disturbances and pressure fluctuations (i.e. of hydrodynamic stimuli) is the locomotory movements of aquatic animals.
For instance, sub-undulatory swimming fish generate a wake with a complex vortex structure (see more info below on this, especially for the swimbait guys out there). Fish living in riverine environments need to contend with considerably more, as they have to differentiate between various “background” noise and potential prey.
In terms of displacement, the main spectral amplitudes of fish-generated hydrodynamic stimuli are usually below 10 Hz, but higher-frequencies might also occur. Thus – fish, particularly predatory fish like bass, are very tuned to subtle
variations and just detecting a bait does not equate to eliciting a bass to strike a bait (how many fish will follow a wakebait, or ripbait, but not eat it). We don’t know how much this naturally occurs as well.
Even if the fish are small, the vortices in fish-generated wakes last for more than 30 seconds and water velocities significantly higher than background water motions can still be detected after three minutes (swimbait guys).
Fish wakes provide some information about the size, swimming style and swimming speed of the wake generator and, therefore, probably also about the type of fish that produced the wake.
Animate sources of natural hydrodynamic stimuli are usually not stationary and rarely vibrate with constant amplitude and frequency.
River2Sea Tactical DD Crankbait