The Book on Bass

One of the most remarkable developments of my years at In-Fisherman was already underway when I joined the staff in 1988. That summer, we received prototype samples of the first Berkley PowerBait softbaits to test. This marked the beginning of my familiarity with Berkley’s involvement in producing lures specifically designed to appeal to fish through their sensory systems.

One of the most remarkable developments of my years at In-Fisherman was already underway when I joined the staff in 1988. That summer, we received prototype samples of the first Berkley PowerBait softbaits to test. This marked the beginning of my familiarity with Berkley’s involvement in producing lures specifically designed to appeal to fish through their sensory systems.

As I’d worked as a fishery biologist myself until 1988, I was eager to meet the man who had been chosen to lead the company’s biological research into the use of taste and smell attractants. Dr. Keith “Doc” Jones had been hired in 1985, at the recommendation of Dr. Herman Kleerekoper, who had served as Jones mentor and graduate advisor at Texas A&M University where Jones earned his Ph.D. Kleerekoper was one of the world’s foremost experts in the role of olfaction in governing fish behavior, and had been hired as a consultant by Berkley when company leaders, notably CEO Tom Bedell, had decided to focus on scientific principles in designing lures. When Kleerekoper couldn’t commit to full-time employment there, his talented protege was selected. The rest is history, familiar to veteran In-­Fisherman readers and anglers versed in fish sensory abilities.

The Beginning

I recently chatted with “Doc” Jones, who retired in 2017, about his career and especially one of his great gifts to anglers—bass anglers in particular—his book, “Knowing Bass,” published in 2002. In the years since, I’ve pored over its pages that reveal in scientific detail how bass function in their environment. It has informed my writing on this subject and made me a better angler. Jones succeeded in presenting extremely technical details of fish physiology so that anglers who read it closely can understand these fascinating details about this wonderful fish.

“My Dad took us fishing when I was a kid, both along the coast near our home in Durham, North Carolina, and in local rivers,” Jones recalls. “We were casual bank anglers.” While this introduction to angling may have stirred his interest in fish, it was the famous undersea explorer Jacques Cousteau who fired Jones’ imagination about the underwater world.

“I was in high school and became enthralled by the TV show, ‘The Undersea World of Jacques Cousteau,’ produced by the French filmmaker and researcher. I immediately knew I wanted to become a marine biologist. I majored in biology, but soon realized I was more interested in fish physiology and sensory mechanisms than ocean life. It’s ironic that I ended up spending my career at a location (Spirit Lake, Iowa) that’s about the farthest point in the U.S. from any marine environment. When I met CEO Tom Bedell and his staff, I was immediately impressed that they were hiring me to do serious research and not a program that could be promoted just to sell more lures.”

One of Jones’ early tasks was to establish a lab to begin testing fish. A cooperative agreement with the Iowa Department of Natural Resources provided the water supply, tanks, and apparatus to begin work. With trout and catfish readily available at the hatchery, species known to possess powerful olfactory capabilities, they became the first subjects of his research. Berkley Strike was one of the earliest products of this work, which transitioned to a lab in Berkley’s main building in Spirit Lake in 1988. Over the next decade, Jones presided over a growing research schedule, as the lab and lure-testing facilities were expanded to fill these needs. Breakthrough products included Trout Bait, PowerBait, Gulp!, MaxScent, and more.

Important Questions

Jones did a masterful job in “Knowing Bass” of bringing together a wealth of scientific information about fish behavior, integrated with his research findings at Berkley. Its subtitle, “The Scientific Approach to Catching More Fish,” gives an indication of its purpose. He focuses on how bass use their senses of sight, smell, taste, hearing, and the lateral line, while also addressing their sense of feel, ability to detect and avoid areas of poor water quality, and he weighs in on the subject of whether fish feel pain.

This book brings a unique level of scientific scrutiny on what has traditionally been a somewhat superstitious pastime. As an angler, he has the ability to communicate highly technical biological details to an audience of folks who may not have studied biology. When asked how long it took to complete,” he replied, “about two years—long enough to drive my family crazy!” Based on my reading of this book, I composed a few questions for Jones, topics I’m often asked by avid anglers:

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SQ: You have noted that senses of feel/touch are important to bass. What is the most important aspect of these senses for anglers to be aware of?

KJ: From an angler’s perspective, by far the most important aspect is how bass perceive bait/lure texture. Lacking hands or fingers, they use their mouth for “handling” things. This includes both investigating novel objects out of curiosity and manipulating food items for swallowing. Most of their natural prey are rather soft and squishy, so bass naturally tend to favor those textures when selecting food items. That bias carries over to artificials. In our tests at the Pure Fishing Research Center, when bass could freely attack softbaits, average retention times typically lasted several seconds, often much longer. In contrast, average retention times for hardbaits, like spinnerbaits and crankbaits, were generally less than a second. Anglers should consider this when choosing lures. When bass are aggressive, the disadvantage of low hardbait retention times may be offset by the larger amount of water fished and the more bass encountered. But when the bite is slow, longer retention times for softbaits help offset the disadvantages of fishing slower.

SQ: Can you describe a likely scenario when a bass detects sufficient molecules of an attractive substance, mixed as it may be in a virtual “soup” of scents and flavors that surround it in a lake?

KJ: The short answer is that bass detect a chemical attractant only when its concentration is significantly higher than background levels. Water chemistry varies considerably from one watershed to another, so there’s no quick calculation to tell what those magical concentrations need to be. But note that on the chemo-sensitivity scale, bass have moderate abilities of smell at best. In practice, a bass generally needs to be within a short distance of a scented bait for the attractant to have an alluring effect. But once it’s taken into the mouth and makes contact with the taste buds, the issue of chemical competition from surrounding water is minimal.

SQ: What might be the range of distances for detection of such substances, given the variables of current, concentration, etc.?

KJ: For smell, I’d guess a bass would need to be within a few inches to a few feet of the scented bait, depending on how much scent it’s emitting.

SQ: How would you best explain the differences between near-field and far-field aspects of hearing and how anglers can best utilize their properties to catch bass?

KJ: Any object moving in water—a branch falling, a minnow swimming, a crankbait moving—generates two physical effects. The first is a pushing of surrounding water to produce micro currents; the second is a squeezing of surrounding water molecules to produce compression waves, what we typically call “sound.” Once generated, both micro currents and compression waves spread out from the source, but the micro currents die out much faster than the compression waves, which extend far and wide.

The area around the moving object wherein the energy of the micro currents dominate (which is immediately adjacent to the moving object) is called the Near Field. The surrounding area beyond the Near Field, where the energy of the compression waves dominate, is termed the Far Field. In fish sensory biology, the lateral line (which detects water flow) is stimulated primarily in the Near Field, whereas the inner ear functions best in the Far Field. There is a considerable body of research showing that freshwater predators like bass use their lateral lines within the Near Field to stimulate and direct feeding strikes.

For bass, there appears to be a strong interplay between vision and the lateral line for feeding. Losing either of these senses leaves the bass less able to capture moving prey. There’s virtually no research showing predatory fish like bass use their sense of hearing to feed. Yet anglers know from experience that sound-producing lures like poppers, buzzbaits, and rattling crankbaits can be highly effective, even though science has shown that the sound output of these lures lies mostly outside the hearing range of bass. We’re still waiting on science to resolve this apparent paradox. Until then, it’s enough for anglers to know that sound-generating lures like the ones I mentioned seem able to “call” in bass from a distance, though not a long distance. The intricacies of stimulating the lateral line only come into play when the bass is near the bait. But I don’t know of anyone who has determined what motions in the Near Field work best.

SQ: In clear and shallow water, might naturally colored lures, such as crayfish or baitfish hues, attract more strikes, all else being equal?

KJ: No, I wouldn’t say that. I’ve never been a believer in the natural-color concept. When someone can show me a baitfish with a firetiger pattern, then I might change my mind. What I’d say is that under the conditions you state—clear and shallow water—the full spectrum of a predator’s color vision, and thus its ability to discern and discriminate lure colorations, is at its fullest potential.

One might suppose that lures with distinct, recognizable color patterns—natural or not—would be most effective there, but that’s not necessarily so, for two reasons. First, just because bass can see certain color patterns better in clear, shallow water doesn’t mean they tend to favor them. Visual detection/recognition and behavioral preference are two entirely different things. Second, the characteristic look of a prey in the eyes of a predator—the key visual pattern it may be looking for—could be limited to the photic environment where the prey is normally encountered. Outside that realm, it may be largely unrecognizable. For example, let’s say a smallmouth normally preys on a certain species of crayfish at depths of 20 feet or more where the color red is greatly diminished. Under those conditions, the crayfish probably looks a dull grayish brown. But if the bass sees that same crayfish in clear, shallow water where the crustacean’s normally brilliant red color now stands out, would the color pattern still match what the smallmouth is looking for? Probably not.

SQ: Might the bass’ ability to discern reds explain the popularity and effectiveness of reddish crankbaits and rattlebaits?

KJ: Absolutely. Recent research has shown that bass have their best color vision in the “red” zone of the spectrum and, secondarily, in the “green” zone. That means when it comes to discerning one color from another, or discerning minor differences in shading of the same color, bass have their strongest abilities in distinguishing reds. So, among the many red (and red-orange) crayfish patterns, even seemingly insignificant differences in color shadings might have meaning for local bass. The same is true, to a lesser degree, for different green firetiger patterns.

SQ: How would you define the “strike zone?”

KJ: The strike zone is an imaginary space or “bubble” around a predatory fish that delineates the maximum distance in all directions the fish is willing to attack. The shape of the space is determined primarily by the fish’s sensory capabilities, for most predators their sense of vision. The overall size of the strike zone varies considerably depending on several factors, notably light conditions, water clarity, obstructions, and the aggressiveness of the predator.

New Perspectives

When I asked Jones about changes to his thinking in regard to bass behavior since publication of “Knowing Bass,” he immediately noted our recently expanded knowledge of the way black bass use their sense of hearing. “While I was at Pure Fishing, our team investigated sound and light as potential bass attractants,” he says. “We tested the effects of sound-producing devices on the market, from lures that click or pop to deck-mounted units with a waterproof speaker to project sounds underwater, as well as other experimental sound production systems.

“Since sound is so potentially powerful under water, given its speed and potential distance of transmission, we were surprised to find that bass didn’t respond at all. We also tried light of various colors, strengths, and pulse patterns to determine if bass were attracted or spurred to feed. As manufacturers of such devices point out, bass will chase the point of a laser pointer across a tank like a cat after a piece of yarn. But that doesn’t equate to getting them to bite.

“In the book, I hypothesized that sounds within their hearing range, around 50 to 300 Hz, and lacking excessive background noise, might arouse fish to evaluate them and search for the source. This might be followed by closer analysis with the lateral line, as well as its eyes and chemical senses. In earlier tests at the lab, we did find minor differences in the reaction of bass to lures (crayfish baits and crankbaits) with rattles, compared to identical ones without rattles. Craws with rattles got more strikes than plain ones, but crankbaits without rattles scored higher than rattling ones in these experiments. These tests were done in clear water and differences ranged from 20 to 25 percent.

“Since then, we’ve gotten a better understanding of how bass may or may not use their sense of hearing for feeding. Dr. Carol Johnston, then a professor at Auburn University, did a series of experiments with redeye and Alabama bass. She’s an expert on sound production and detection among members of the sunfish family, which of course, bass belong to. Her experiments showed that redeye bass produce sounds within the hearing range of bass during aggressive encounters with other redeye bass. The more aggressive bass made most of the sounds following an attack or territorial display.

“In other experiments, she found that sounds produced by spawning tricolor shiners, a favored prey, didn’t attract redeye bass, suggesting that the fish didn’t use their sense of hearing for feeding. In that paper, she states, ‘No studies to our knowledge have shown a predator being attracted to the sounds produced by prey in freshwater fish.’ Johnston also tested the hearing range of redeye and Alabama bass and compared them to an earlier test of largemouths, finding them all most sensitive in the range of about 100 to 300 Hz. Redeye bass, however, did detect higher-frequency sounds than Alabama bass. So there’s certainly a lack of evidence that bass use hearing to feed, something we we’re sure of when I wrote the book.”

Reflections

From his home on St. George Island, Florida, Dr. Jones reminisced about some of the high points of his work at Pure Fishing. “I haven’t regretted retiring,” Jones told me. “I enjoy the free time and flexible schedule that lets me go fishing whenever the wind is not too strong. I’ve become a big fan of kayak fishing, so I watch the weather.”

I asked about the most rewarding aspects of his 32 years of research at Berkley. “One thing that stands out for me,” he says, “was the wholehearted support I enjoyed from the company’s upper management. Tom Bedell and later managers never asked us to cut corners or to rush our results to bring products to market. Our research operated independent of marketing and production and advertising, and for that I’m eternally grateful, though in truth, I wouldn’t have stayed if that wasn’t the case.

“The thing I’ve missed most about retirement,” he continues, “is not being involved in the research that we conducted at the lab. My successor, Brent Southworth, is an outstanding biologist and he’s made many improvements in our facility there, and continues to conduct groundbreaking research. The staff has expanded from lure development using the same scientific testing and standards to produce new generations of rods and reels.”

“Knowing Bass,” published by Lyons Press, has been out of print for quite a few years. It’s available on eBay and other online sellers, but prices run from about $125 to $175. That’s a shame for readers who didn’t get a chance to buy a copy when it was in print. But at In-Fisherman, we continue to provide scientific details from Jones’ book and other important publications on the pages of this magazine and our annual guides. Stay tuned.

*Steve Quinn was an In-Fisherman Staff Editor for over 30 years and now serves as a Field Editor. He’s a fine multispecies angler, but his longtime specialty has been in-depth writing about the bass species.