Dr. Juice was sitting at the dining room table in his home on the shore of Lake Superior in Duluth, describing the trials and tribulations of his latest research as he prepared for a fishing trip to Isle Royale.

He's really excited now about kairomones - scents critters release when they are being chomped to pieces by predators, and he's thinking they'll be the next big thing in fishing tackle.

A self-taught fisheries scientist, semi-retired psychiatrist, tinkerer, underwater photographer, sales pitchman and avid fisherman, Dr. Juice - a.k.a. Greg Bambenek - has a new product he wants anglers to buy so they can land more fish. It's his first new scent in more than a decade.

It's called Kairomone Scent and it's packed with dimethyl sulfide, Bambenek said, the kairomone given off when the cells of phytoplankton and algae are being chewed up by zooplankton and small fish.

Bambenek said the dimethyl sulfide scent triggers a feeding instinct among all fish in lakes, rivers and oceans.

"Little trout feed on algae, too. And they feed (on the zooplankton) that eat the phytoplankton. So that smell, that kairomone, means food to them at a very early age,'' Bambenek said. "It's a powerful trigger to eat that stays with them."

The good doctor claims the stuff has improved the catching of trout and salmon on his son Parker's Bambenek's Superior Pursuits charter fishing Lake Superior by 50 percent compared to lures trolled at the same time without it.

"But as soon as the customer sees what's going on, they want the stuff on every lure in the water, so that's the end of the research," Bambenek said, adding that North Shore commercial netters have used the stuff to attract more trout and herring to their nets.

Powerful magic

Dr Juice is back, although it's not like he ever really went away.

You probably recall Dr. Juice from the 1980s and '90s. The scents were "powerful magic," the Dr. Juice TV commercials claimed, with jungle music in the background and a hint that the recipe came from witch doctors (Parts of that sales pitch are true: Bambenek studied in the jungles of Belize and Taiwan where he found medicine men using scents to catch fish).

Dr. Juice became synonymous with his jungle-style hat (with a snakeskin wrap) which Bambenek still wears when he's promoting the product.

Anglers gobbled the stuff up. And they're still using scents big time. A check of any big fishing tackle store - Cabela's, Fleet Farm, Marine General, Gander Outdoors, etc. - will show dozens of different scent options to spray, dip or drip on fishing lures, including the original Dr. Juice scents. And that doesn't include scent-impregnated lures like fake worms and minnows.

"Scents are a pretty big segment of the (fishing tackle) market. Dr. Juice is still selling for us, especially the Trout & Salmon scent,'' said Russ Francisco, owner of Marine General sporting goods in Duluth. "We get a lot of serious crappie fishermen in Florida and Michigan ordering it (online) from us. We have an end cap in the store dedicated to Dr. Juice and we have to keep stocking it, so somebody is using it."

Pheromones to kairomones... and herring farts in between

Bambenek grew up in southeastern Minnesota, along the Mississippi River, where he watched, and smelled, as his dad used scents to attract catfish.

"He'd put some stuff on and I watched him haul-in 70 pound flatheads. That fish can smell apparently stuck with me for life,'' Bambenek said.

When Dr. Juice first appeared in the early 1980s, Bambenek was among the first to promote the use of pheromones to catch fish. Those are the scents that species emit to attract others of the same species - like doe deer in heat emit pheromones to attract bucks, or that minnows emit to keep their school together.

His species-specific Dr. Juice scents are said to be packed with "sex pheromones, fear pheromones and schooling pheromones" that each species emitted to attract their own kind.

Dr Juice for several years was promoted by global fishing tackle giant Rapala, although that agreement has ended, which lowered the brand's profile for several years.

Meanwhile a recent foray into fish sounds, including an Iphone app and underwater speaker system called TalkWithFish that anglers deploy to attract fish, has not sold as well as he hoped. (the fish sounds include rushing water and herring farts).

Bambenek, 70, now is passing on the Dr. Juice business to his sons Jacob, the CEO, and Parker, vice president of research and development. Greg is now laser focused on kairomones, the scents preyed-upon things emit, unwittingly, that attract predators. Humans exhaling carbon dioxide is a kairomone mosquitoes use to track us down and bite us.

Science shows it's so

The more reading Bambenek did on the subject the more he learned about how little sea and lake creatures emit oodles of dimethyl sulfide when their cells are busted open, and that dimethyl sulfide acts as a kairomone to bigger critters in the water. Huge amounts of the stuff are emitted from algae, phytoplankton in the ocean, on a constant basis - so much so that it contributes to the cycle of weather, spurring clouds, rain and cooling - controlling the climate over the ocean.

"This stuff (dimethyl sulfide) can actually help slow global warming,'' Bambenek says, although he concedes anglers could never use enough of his new fishing scent to make a difference.

Bambenek cites multiple scientific studies, peer reviewed and published in mainstream scientific journals, that confirm dimethyl sulfide attracts seabirds, turtles, mahi-mahi fish, seals and even penguins - all of which hone in on the dimethyl sulfide smell to find schools of small fish.

He called the first scent with dimethyl sulfide Shrimp Scent, aimed at saltwater anglers, with newly-named Kairomone Scent aimed at freshwater species. Bambenek has tried it himself to catch lake trout at Isle Royale and tuna and sea turtles in Hawaii.

Dimethyl sulfide is the basic element in what people smell when they get a whiff of the ocean.

Open a bottle of Kairomone Scent, take a whiff and it smells like... sweet, rotting cabbage.

"That's the universal scent of the sea," Bambenek noted.

The Bambenek's delivered the first boxes of Kairomone Scent to Marine General, Fisherman's Corner, the Bait Box and Chalstroms last week. It can also be ordered online at drjuiceusa.com for $8.99 for a 4-ounce bottle.

Time will tell if Northland anglers, and fish, are attracted to the stuff.

"I'm sure it will work,'' said Francisco. "Greg is a scientist first, a physician second. He knows his stuff. He knows how to catch fish."