Smell

A close look at a perch’s snout reveals a pair of nostrils or nares on each side. The forward opening where water enters the olfactory chamber and the rear port where it exits is visible. Inside each chamber, water washes over the feathery olfactory organ, where sensors detect dilute concentrations of substances. Eels and minnows are the most sensitive sniffers, while trout and salmon have far more powerful olfactory abilities than bass, walleyes, or perch.

Still, perch likely use their sense of smell in the decision whether to bite a bait. Hence the attraction of a minnow head or the traditional perch eye (illegal in some states). And applying a formula, whether an extract of natural prey like shad, crayfish, minnow, leech, or an artificial amino acid concoction, can in theory increase odds of perch biting and holding an artificial. Thicker paste formulas, of course, adhere to a lure longer, and sponge or cotton accessories hold flavors well.

Taste

Like smell, a fish’s sense of taste occurs in a medium where molecules are dissolved in water. As a result, it is hard to distinguish whether olfaction or taste is responsible for a reaction. Unlike catfish and other barbelled species like carp, burbot, and drum, perch have taste buds only around the lips and mouth.

Taste is important to all fish, as it can distinguish dinner from disaster, often the final barrier between fish and fisherman. I’ve watched perch inhale a bait, decide it was objectionable (despite an apparently tasty package) and eject it in a split second, without the angler ever knowing he was bit. Even a minifloat may barely quiver. And, even if the angler knows he had a bite, no reaction is fast enough.

The lab staff at Pure Fishing are leaders in flavor formulas, but they have not yet tested perch, nor tailored a flavor for them. Flavors found in natural foods likely encourage fish to hold a bait, and live or recently killed minnows are rarely rejected. Maggots of various sorts, leaking their life juices, also are favored.

Movements and Habitat

Specific sensory systems of the perch have not been studied, but some tracking studies of yellow perch have been done. One in Wisconsin, using radio transmitters, proved that perch, at times, suspend above the thermocline, then dive through 30 feet or more of unoxygenated water to feed on bottom-dwelling worms before rushing back above the thermocline like little pearl divers.

Fishery researchers from Nova Scotia also found that yellow perch break into groups at spawning time, returning to places where they had previously spawned. Late winter is a time of transition for perch. Studies and angler efforts both indicate that perch move in winter, and the larger the environment, the farther they tend to wander.

In early winter, their movements probably are related to forage needs and avoiding predation. After cropping down an area, they move on to more fertile feeding grounds, or to keep larger schools of predators from getting a fix on them. Perch are a prized catch for walleyes and pike, too. And by late winter, perch may begin to move in the general direction of spawning areas, especially in larger lakes.

During winter, preparation for the spawn seems utmost in the minds of perch. As winter progresses, the size of perch ovaries and testes grows, fueled by heavy feeding. By late March, big females are so fat they can hardly swim. The result is generally good perch action, once the fish are located.