The Wheelhouse Scoop: Outsmarting fish

DINA MARTINO and Scott Manson with a local white seabass caught with guide Gerry Mahieu.


Angler critics occasionally quip regarding anglers’ embellishment of their outwitting wily fish — like how great of you, you outsmarted a fish. That’s some huge accomplishment for you — a compliment that’s not. Yeah, outsmarted a fish with a brain the size of a peanut at best. But any angler can tell you, fish can be finicky, particular, stealthy, have a sixth sense for things we have no sense of.

It can be something be subtle but within human sensory abilities, like hook size, line size, bait type, a scent. These are things we can understand.

But it can also be sublime, fish senses we fail to appreciate. Many fish can sense electrical fields, like those cast off by dissimilar metals touching, or for commercial salmon trollers, some small current running down the wire from the boat.


Some kinds of fish hunt the seafloor and muddy-water river bottoms, sensing the subtle fields kicked off by organisms buried below. We used an e-field device to measure field strength coming off sub-sea power cables, and sometimes to find the cable-lay itself where it disappeared beneath the sand.

A bit of research dive humor came from shopping for these devices, none of which were waterproof, requiring us to use a clear waterproof box to house it. It turned out most of the websites selling these things were focused on ghost hunters searching old houses, fraught with unshielded wiring for signs of paranormal occupation.

A little insight and it was clear modern ghost hunters were a bunch of shysters, bilking the uninformed by scanning their vintage homes for what they knew was likely there, lots of old-school wiring. Thus, we referred to our tool in our dive research kit as the “ghost meter.”

Sharks have e-field sensor organs called the “Ampullae of Lorenzini”. Sharks can sense the putative paranormal too, it seems.

Freshwater fish are especially attuned to subtle vibrations, feeling footsteps translating from 50 feet off the bank, putting said critter on alert and somehow that pea-brain holds the wherewithal to instantly switch from predator to prey mode.

Fish are in water and can “taste” or “smell” chemical cues not just inside the noses and mouth, but from just about anywhere on their bodies, occurring mostly on their heads and faces though.

Their lateral line system is subdermally interconnected pores with sensory hairs hidden within. The best way to describe what they sense is “distant touch”. Water is uncompressible and when they swim by a stationary object or something swims by them they can feel it, feeling out to at least several inches away, maybe several feet.

Schooling fish swim in synchrony following several basic rules with respect to their nearest neighbors, and using this distant touch. As you might imagine, in the dark this is the magic sense that keeps synchrony from becoming chaos.

People tend to think of smarts in terms of cognitive abilities, ease of memorization, problem solving, sentience, sense-of-self etcetera. But the reality is much different. Mental ability is often compartmentalized and then synthesized.

The absolute “smartest” things organisms do are hard-wired abilities, fined tuned by practice, and for us, mostly very early in life. One is spatial organization of sight, seeing, coordinating your eyes to a single view, understanding distance and size.

People chide others saying someone can’t walk and chew gum at the same time. Yet, if one were to analyze what it takes to walk in terms of calculus, pencil and paper, even a calculator, a pro would be there all day to make up the first five steps by the numbers, muscle tension, balance, direction of down, momentum, acceleration, thrust, changes in acceleration, changes in the change in acceleration.

The parts of our minds that do these tasks are far more powerful than our thought processes, and it’s done subconsciously.

Now consider playing team sports, running, dodging, juking, tracking team mates and opponents’ movements all the while — the synthesis of unconscious intelligence in motion, sight, hearing and conscious cognitive ability, speedy problem solving and planning.

People learn unconscious ability too, playing a musical instrument so you are thinking the notes rather than the fingerings, typing, casting by focusing on the target and otherwise, simply feeling “the force.” Folks learn to run heavy equipment with piles of spooler valves, leavers, buttons without looking down at them, instead watching progress — the bucket, crane load, boat.

Driving a car is one of these practice things, too. It can become so “unconscious” we need to prod ourselves to put down the phone or sandwich and pay attention to traffic. Now consider a bird landing on a wire — that’s skill! Or even a June bug ripping through the brush and trees.

And yet you can see the shortcomings of such mostly hard-wired or at least heavily pre-disposed intelligence coming in a small package. While navigating by keeping the moon at a fixed angle works great for moths, navigating this way using the porch light ends up with tight concentric circles — then the moth smacks into the light bulb, again!

Strangely, that’s pretty similar to the way many boaters end up pulling a full circle around a sportboat, coyly trying to see if they’re catching without actually stopping and staring. So much for being smarter than a bug.

So that fish, hovering in position, occasionally switching sides next to a kelp frond in the switching surge, fanning fins, is a tremendous demonstration of fish “smartness” — one the best in robotics would have a difficult, if not impossible task in replicating with the smartest AI chips, thrusters and optical sensors made.

Fish ARE smart in their own mostly hard-wired way. Beyond that, most of one’s mental abilities have little to do with those abilities we commonly refer to as intelligence, and are far more remarkable. These are characteristics people share with other predators and prey alike.

Think about that the next time a fish hammers your topwater bait as soon as it hits, clearly having tracked it in the air, quickly calculated its landing position, got there and was ready for it.

Merit McCrea is saltwater editor for Western Outdoor News. A veteran Southern California party boat captain, he is a marine research scientist with the Dr. Milton Love Lab at the University of California at Santa Barbara’s Marine Science Institute. He serves on the Groundfish Advisory sub-Panel of the Pacific Fisheries Management Council, the Santa Barbara Harbor Commission, the Channel Islands National Marine Sanctuary Advisory Council and the CCA-Cal State Board. He can be reached at: