Ep 3: “What Is a Reflex? Fish Are Smarter Than You Think”

Chapter 1: How Fish Find Their Food

Episode 3: “What Is a Reflex? Fish Are Smarter Than You Think”

Recap

(The Professor enters, writing “Sound & Waves → Scent → Sight” on the blackboard.)

Professor: “Last time, we learned the order in which fish detect a lure. They notice it by sound, verify by scent, and finally confirm with their eyes.”

Student: “And when they’re in a rush, they skip the verification steps — that was… a reaction bite, right?”

Professor: “Exactly. Today we’re going to dig deeper into what ‘reflex’ really means.”

Bass-kun: “We’re doing this again, huh…”

Professor: “Bass-kun, you seemed awfully interested in the soy-sauce-instead-of-Coke story last time.”

Bass-kun: “Th-that was just…”

Masu-kun: “Someone did say, ‘How does a fish even know about Coke?’ — but you did know, did you not?”

Bass-kun: “…Drop it, dude.”

“Fish Forget in Three Seconds” — Fact or Fiction?

Professor: “Now then. There’s a popular claim out there: ‘Fish forget everything in three seconds.’”

Student: “Oh! I’ve heard that! That’s why you can catch them on the same lure over and over…”

Bass-kun: “…Are you serious right now?”

Masu-kun: “That is only true of certain individuals. It is not a general fact.”

Bass-kun: “If we were all that dim, we wouldn’t have survived the Ice Age, man. Show some respect.”

In reality, fish memory is far more impressive than most people assume. Experiments with bass have shown that a conditioned response, once learned, can be retained for over six months — and in some cases, nearly a year. “Fish forget in three seconds” is a baseless myth. There may be some individuals like that — but that’s all it is.

Professor: “In fact, it’s the opposite. Most fish hold onto what they’ve learned for a long time. And for anglers, that creates a problem.”

Student: “A problem? How so?”

Professor: “Are you familiar with the concept of pressure?”

Student: “…You mean when fish start ignoring lures, right?”

Professor: “Precisely. It means the fish have learned.”

How Fish Get Pressured

When fish get pressured — when they start ignoring or fleeing from lures — it’s because the memory of a bad experience has been linked to the signals associated with it.

Professor: “Say a fish gets caught on a lure that makes a high-pitched, shimmering rattle. That fish connects that sound with ‘danger’ and learns to avoid it. From that point on, whenever it hears that same sound, it goes on alert.”

Bass-kun: “Yeah… I’ve been through that enough times that I really can’t argue.”

Masu-kun: “At certain fisheries, any lure will get a response for the first few casts, but the bites gradually taper off. That is precisely this mechanism at work.”

Professor: “What makes it even more troublesome is that this can spread through a school.”

When the first fish caught from a school — often a key individual — doesn’t return, or when it sends out distress signals, the entire school can shift into a state of heightened alertness.

Student: “So when you catch one fish and the whole spot goes dead — is that why?”

Professor: “In some cases, yes. If the fish you caught was a leader-type individual in the school, and the rest of the group witnessed a prolonged fight, they can scatter all at once. That’s why sometimes it’s effective to land the fish quickly and move on — but that’s a fishing technique discussion for another day.”

Bass-kun: “Land the fish and ‘move on’… that’s a pretty ominous way to put it” (mutters)

Fish Aren’t Dumb — and That’s Exactly Why They Get Caught

Professor: “Let’s shift perspective for a moment. Fish learn. Fish remember. Fish get pressured. That sounds like bad news for anglers, doesn’t it?”

Student: “Right? If they’re smart, shouldn’t they be harder to catch?”

Professor: “And yet — it’s precisely because they’re smart that they get caught. That’s today’s main topic.”

Let’s clarify something here: there are two fundamentally different types of reflex.

Professor: “The first is the unconditioned reflex — an innate response that happens without any learning. The second is the conditioned reflex — a response acquired through experience.”

Student: “What’s an example of an unconditioned reflex?”

Professor: “Touch something hot, and you pull your hand away before you even think about it. That’s an unconditioned reflex. No learning required.”

Bass-kun: “For us, it’s like… when something shiny moves suddenly, you lunge at it without thinking. That kinda thing.”

Professor: “That would be a type of unconditioned reflex, yes. A signal that resembles prey movement triggers a response before any verification takes place.”

Masu-kun: “As a stream-bred fish… when something lands on the water surface, I sometimes dart out before I have had time to think.”

Student: “Isn’t that basically… instinct?”

Professor: “Exactly. Instinct and unconditioned reflexes are closely related. And here’s the key — they are resistant to pressure.”

This is a critical point. Responses rooted in instinct are not easily overwritten by learning. So even in a heavily fished area, lure actions that tap into instinct tend to keep producing bites.

Professor: “Conditioned reflexes, on the other hand, can be pressured. But precisely because conditioned reflexes exist, anglers can turn them to their advantage.”

Student: “Turn them to our advantage?”

Using Conditioned Reflexes

Professor: “Let me describe an experiment. In a tank, we showed bass a red panel on one side and fed them exclusively from that direction. After one week of this…”

Bass-kun: “Oh, I know where this is going. They learn that heading toward that side means food’s coming, right?”

Professor: “Correct. After two weeks, every single fish in the tank was responding to the red panel and waiting for food — despite the fact that bass naturally tend to favor green.”

Student: “Wait — can’t we use that in fishing?”

Professor: “You already do. At a stocked trout pond, fish that have memorized feeding times will gather on their own when that time of day comes around, won’t they?”

Masu-kun: “I know exactly what you mean! The same thing happens in hatcheries. Fish learn to associate a sound or light signal with feeding time.”

Professor: “Right. Fish learn the condition: ‘When this signal comes, food follows.’ At bait fishing ponds, if an angler fishes the same spot at the same time repeatedly, the fish will — after a few sessions — start anticipating the angler’s arrival. It does happen.”

Bass-kun: “…The more I hear, the weirder this feels, man.”

Why Is the Golden Hour So Good?

Student: “Is the dawn golden hour — mazume— or the dusk golden hour — mazume— related to conditioned reflexes?”

Professor: “Absolutely. A change in light triggers plankton to move, which triggers baitfish to move, which triggers larger predators to move — this food-chain cascade repeats every day. Fish learn this rhythm as a condition.”

Masu-kun: “When the light begins to change, I start to feel hungry, so to speak. As a stream-bred fish, the sensation of dawn feels as though it is woven into my very body.”

Bass-kun: “Mornings are busy for me too. My body just starts moving on its own, y’know?”

Professor: “That’s a conditioned reflex. The signal of changing light has become linked to feeding behavior. So when anglers target the golden hour, it’s well-founded.”

Student: “…Does that mean it’s harder to catch fish outside of the golden hour?”

Professor: “Not necessarily. I’ll get to this another time, but I believe bass likely shift their daily activity patterns with the seasons. And lure actions or sounds that trigger instinct can produce bites regardless of time of day. The point is simply that during the golden hour, those conditioned reflex triggers are stacked in your favor — making it easier to catch fish.”

Why Rotation Matters

Student: “Going back to the pressure thing… what do you do when fish are pressured?”

Professor: “Rotating your lures is exactly the answer. If you repeat the same sound, the same action, the same color, fish learn to flag those as ‘danger signals.’ By switching to a different signal, you can bypass their learned defenses.”

Bass-kun: “Yeah, basically. When the same lure keeps coming at me over and over, it’s like, ‘Oh, this again.’ You just stop caring.”

Masu-kun: “As a stream-bred fish… dry fly patterns in particular are quite delicate. Once I have seen through a pattern, I do not respond to that same one again for some time.”

Professor: “On the flip side, if you wait a while and throw the same lure again later, you can sometimes get a response. The memory doesn’t erase, but it seems that the priority attached to it can shift over time.”

Student: “So casting the same lure at the same spot over and over is…”

Bass-kun: “Not gonna work unless something pretty crazy happens, honestly.”

Professor: “Though ‘something pretty crazy’ is also part of the beauty of fishing. An action that powerfully triggers instinct, an approach that comes from completely outside the fish’s line of sight — even when conditioned reflexes have them on guard, instinct can override the alarm.”

Student: “This goes deep…”

Today’s Summary (Blackboard)

(The Professor writes a summary on the blackboard.)

📋 Key Takeaways

• “Fish forget in three seconds” is a myth — a conditioned response can be retained for over six months.
• Getting pressured = learning through conditioned reflexes. The danger signal gets stored in memory.
• There are two types of reflex:
• Unconditioned reflex = an innate response. Resistant to pressure. Close to instinct.
• Conditioned reflex = a learned response. Susceptible to pressure — but can be exploited.
• The golden hour produces bites because conditioned reflex rhythms align with the food chain cascade.
• The point of rotation: bypassing learned defenses by switching to a different signal.

Professor: “Next time, we’ll look at how the priority of senses shifts depending on conditions — clear water, murky water, and night fishing.”

Student: “So the approach changes depending on the environment?”

Professor: “Exactly. Even the same bass lives in a completely different perceptual world depending on water clarity and light levels.”

Bass-kun: “…Come to think of it, a muddy pond and a clear pond do feel totally different. Like, my whole vibe changes.”

Masu-kun: “The clear water of a mountain stream and the murky water of a lowland river feel entirely different as well. I wonder if it is because the way I use my eyes changes…”

Professor: “That’s exactly what we’ll discuss next time.”

Next time — Episode 4: “Clear, Murky, Night — How Fish Switch Their Senses”

About This Series

Beyond TULALA: Professor Ogawa’s Fish-Eye Field Notes is a serialized science-of-fishing book originally published in Japanese. The series explores fish biology, sensory science, and lure fishing theory through educational dialogue between four characters: Professor Ogawa (a rumpled scientist), Bass-kun (a largemouth bass with attitude), Masu-kun (a polite rainbow trout), and a Student who represents the reader.

About the Author

Professor Ogawa is the pen name of Kentaro Ogawa, rod designer at TULALA — a Japanese fishing rod manufacturer. Drawing on his background in fish biology research, Ogawa brings decades of scientific observation and lure design experience to this series. The views expressed are based on his own research, experiments, and fieldwork over the years.

TULALA: https://tulala.jp/