Inside Angles: When What Anglers Know Isn't Exactly So

Bits and Pieces, an In-Fisherman column that began almost five decades ago, continues to this day in the same way as it was originally envisioned—to connect scientific dots to common fishing situations to enlighten anglers and help them catch more fish. Along the way we enlisted astute fishery scientists who love to fish as much as they love the science associated with fishing and fish management to write the column—and much of the magazine for that matter.

One continuing curiosity has been how counterintuitive some aspects of fishing can be—which is, once again, where science enters the scene, to put things in better perspective. So yes, it makes perfect sense to “match the hatch” when presenting lures, that is, to try to duplicate exactly what we presume fish to be feeding on—except that what fish may be feeding on may not actually be what they prefer.

Many studies have clarified how some fish make food choices. Pike in one study were given a choice of yellow perch, dace, sticklebacks, and fathead minnows. The pike ate the minnows first, then switched to sticklebacks and dace. Perch were least often targeted.

Yet perch are the predominant prey in many North American waters. Apparently, pike and other predators can create their own prey environment, selectively eating prey species they prefer until harder-to-catch species dominate baitfish populations. Eventually a somewhat balanced predator-prey environment develops where harder-to-catch prey are most abundant. But as you see, just because they’re most abundant doesn’t mean they’re preferred.

Of course, the point can be made that at least some predators in such environments will always be looking for perch given that they’re the dominant remaining forage. Or for gobies in many parts of the Great Lakes. So, matching the hatch still makes sense. But the point also is that offering fish something that looks much different might be just as effective or more so.

And there is the testing that was done on crayfish shapes at the Berkley Lab in Spirit Lake, Iowa. Would not one logically assume that bass would prefer a perfectly anatomically correct crayfish shape, one with 10 appendages including two obvious pincher claws?

Yet the preferred shape was one without any appendages—so almost the perfect shape of a tube, which reiterates my longstanding love affair with this softbait shape, which I’ve always called a “generalist shape.” Doesn’t look specifically like anything but looks close enough to be lots of different things. Could be a minnow species. Could be a juvenile bluegill, perch, or crappie. Could be a juicy bullhead. Could certainly be a goby. And now we know it could absolutely certainly be a crayfish.

Berkley researchers also tested which wormlike shapes bass preferred. Longer and thinner didn’t trip many triggers. Neither did shorter and fatter. One might say that bass preferred a moderate shape—moderate length at about 4 inches and moderate thickness at a half inch. So again, a shape not too far removed from a classic 3.5-inch tube.

And what does that say about what has become the classic Ned body shape at 2.75 inches and 3/8 of an inch thick? Seems like we might want to at least experiment with little bit longer and slightly thicker Neds.

It’s also erroneous for anglers to play the color game based on what they think fish can see instead of what science suggests they can see, although admittedly scientists don’t always totally agree either. Lure color is a predominant part of matching the hatch. But before color becomes important, we must be on fish. At that point, lure (or bait) depth control and speed control (how the lure is being worked) are more important than color. Lure vibration plays an extensive role, too.

And then color becomes a concern. No doubt about it though. Color choice can sometimes be the difference between five fish and one fish on a difficult day, the difference between adding a kicker fish to an average bag on and otherwise average day.

Matching the hatch may not always be critical, but knowing what the hatch is usually plays a role in our final working solution. Sometimes it works to match most of the hatch, then to add a touch of distinguishing color like a chartreuse, a red, or an orange to modestly (and at other times significantly) heighten the overall contrast and visibility of the package. Such a touch of color may also play on a fish’s curiosity just enough to get them to sample a lure—a tentative bite. This can work as well with crankbaits as it does with hair jigs, swimbaits, and jigs with soft trailers.

Scientist have suggested that North America’s favorite sportfish, the largemouth bass, has visual peaks in the red-orange and green portions of the spectrum. They also see well orange-yellow and yellow-green. On each side of those peaks, color discrimination drops off. They probably can’t distinguish blues, which they see as something dark. Purples are a no go, too, even though they’re a prime lure color for triggering lure sales. Overall, though, bass can be discriminating in the red-orange and green portions of the spectrum. Once we know what science at least suggests, lure color choice actually becomes more intuitive than counter-so.

Though it may not seem to have much to do with catching fish, science even gives us hints at the comparative learning ability of some fish species. The late Dan Coble, a noted Wisconsin fishery professor, measured how quickly some fish learn to avoid an electrical shock. Stripers, carp, and channel catfish learned relatively quickly; followed by spotted bass and smallmouth bass; and then largemouths; and a bit farther down the line pike and bluegills. At the bottom of the heap, yellow perch were described as “unteachable.” In a sense, this is a test of the ability of fish species to become conditioned to avoid unpleasantness, which should correspond to how quickly they learn to avoid interactions with anglers. And it explains why perch can often seem impossible to pattern.

We often say that each day on the water is an ongoing experiment in action. We take what we know and what we think we know into the field with us to make all kinds of judgements about strategy, from where to fish to what to try catch them with. It’s probably better overall if what we know is actually so.

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