Pavlov's 'Eyes?

A century ago, Russian scientist Igor Pavlov had gone to the dogs--his dogs--to gauge what cues would make them drool. For starters, Pavlov gave them food and watched them salivate. The next step in the experiment was to ring a bell when feeding the dogs, and again their mouths watered. Ultimately, with the bell tolling and without food, Pavlov's dogs salivated in anticipation. These pioneering studies were labeled "conditioned response."

Something similar is intended with scent-based soft plastics and scent applications--ringing a dinner bell for walleyes. Give fish a positive experience with something tasty, aromatic, and soft, the thinking goes, and the fish are apt to eat it.

In tank tests at the Fish Research Lab at Pure Fishing in Spirit Lake, Iowa, scientists have dropped in everything from pebbles to cotton soaked with insect repellent to soft plastics treated with scent to gauge the fishes' reactions. "If it's something distasteful, you can't even use a stopwatch to measure how fast they spit it out," says researcher John Prochnow, a developer of Berkley Power Bait. "If it's something they like, they swallow it right down."

Positive and negative scents have long been a matter of trial, error, intuition, and superstition among anglers. Spray a bait with WD-40, rub it with Preparation H, spit on it with tobacco juice--it's hard to say whether the contributions are anything more than voodoo fish-onomics. Increasingly, with science on their side, manufacturers such as Berkley have performed tens of thousands of flavor tests on bass, walleyes, trout, and panfish to find what the different species like best.

At the same time, designers have developed shapes and textures specifically for walleyes, with a softer makeup for more fluid movement. Examples are Berkley's supple Power Jigworm and Power Minnow. As such, scented plastics as well as scent applications have evolved beyond anise coverups and stiff, motionless worms and grubs to a level of high science. Still, as with any live or artificial offering, the ways in which scent-infused lures and baits are fished--jigging motions, rigging particulars, and trolling tricks--are the all-important complement to their effectiveness.

Wiggle of the Worm

Walleyes are not salmon, a species that detects scent cues in concentrations as low as parts per billion, although the walleye's taste receptors are indeed acute. Witness the legendary preoccupation with livebait, and consider that walleyes have taste buds on their lips and face. "They don't even have to put an item in their mouths to taste it," Prochnow says. "They can almost taste without touching."

If any delivery of scented soft plastics makes the most sense, it's probably with a jig. The reason, notes In-Fisherman Professional Walleye Trail pro Keith Kavajecz, Kaukauna, Wisconsin, is that whether you're tipping with a minnow or plastic, you're giving it motion. "Soft plastics work when you put action into the bait," Kavajecz says. "Typically that means jigging. Even with a live minnow, you give it all the action. The new extra-soft plastics present a flipping action that's like a half-crawler gyrating and flipping."

My own conversion to jigging plastics came via the tutelage and friendship of Cal Stier, whose pet method is snap-jigging 4-inch Bass Pro Shops Squirmin' Worms on a jighead with superline. The worm is flavored with Yum, an enzyme-based scent.