Serious fishermen go to amazing lengths to give themselves an edge. For most of us, this includes using an impressive array of technology ranging from sonar, GPS, underwater cameras and thermally fused superlines to graphite-matrix rods.
Ironic, then, that one of the most important factors in fishing success involves a form of communication that's been around since the dawn of creation: pheromones.
While the biology behind these cryptic chemical messages is incredibly complex, you don't have to be a molecular scientist to understand it well enough to put more fish in the boat. Here's what you need to know about this fascinating facet of fish communication.
"By the strictest definition, pheromones are chemicals, released into the environment, that affect the behavior of other organisms of the same species," explains North American Fisherman's resident science major, Dr. Hal Schramm. These chemical signals trigger instinctive responses on the receiving end, ranging from amorous sexual behavior to flight responses to physical development or change.
And they're hardly limited to fish. A host of living things from plants and insects to humans send messages using pheromones.
Globally, researchers studying a variety of species are laboring to learn the mechanisms and languages of pheromones. Much remains to be explored, but so far, scientists believe that pheromones may be the oldest form of communication. These communiqués assist with everything from romance to aggression. They allow columns of army ants to coordinate invasions. With equal proficiency, they help males and females of countless species attract a mate.
In the vast and often turbid, weed-choked or featureless underwater environments, pheromones let fish keep in touch, so to speak. These chemical messages mainly affect fish of the same species, but Schramm notes that some research suggests members of the same family—such as goldfish and common carp—may detect and react to each other's pheromonal cues.
Because they generally are not picked up by unrelated species, predator and prey pheromones act a bit like secret messages—dispatched without tipping off competitors, enemies or potential victims.
Beyond their biological importance in the web of life, pheromones are important to anglers for a couple of reasons. First, the alarm signals from just one injured fish can shut down a hot bite.
For example, alarm pheromones secreted from the damaged tissues of an injured fish can put other fish on al-ert. And, unlike spoken warnings between humans that can be ignored, pheromones trigger involuntary changes in behavior.
In other words, a largemouth bass that is hooked and lost can put nearby bass on guard, or perhaps even cause automatic responses such as suppressing feeding or swimming behavior (see below).
"I've seen it happen may times," says Schramm. "I'll catch bass one after another from a brush pile until I lose a fish; then the action stops cold."
There's not much we can do about preventing the occasional escapee from warning its schoolmates, but we can quickly get hooked fish away from the target school, structural element or choice piece of fish-attracting cover.
When legal, ethical and biologically sound, we can also tweak our strategies for releasing fish. "If I'm taking bass off a confined spot, I won't release any fish until I'm ready to leave," says Schramm.
If immediate release is mandatory, you might want to factor mobility into your fishing strategies. Develop a milk run of go-to spots, or pluck fish from the perimeters of cover rather than smack in the middle of it. Either that, or accept lulls between bites as part of the game.
"Fish also use sensory receptors to detect pheromones when hunting prey," says Mustad's Bob Funk, a veteran multi-species angler who spearheaded the field-testing and launch of Mustad's new Activate fish attractants.
"Activate products contain a base of fish oils from primary prey and gamefish—that's the attractant," he explains. "In our freshwater versions, pheromones from the target species trigger a feeding response.
"The beauty of pheromones is, fish don't get conditioned to them like they do with scents," he notes. "Pheromones trigger behavior, period."
Mustad offers bass, catfish, salmon, trout and walleye options, plus a saltwater blend. The company is not the only to tap the pheromone phenomenon; Eagle Claw says its Nitro Gravy contains a "cocktail of pheromone attractants."
Skeptical fishermen may wonder whether pheromones can really make fish feed. But considering all the behaviors attributed to them, it isn't much of a stretch to make the leap from basic behaviors such as sex and violence to feeding.
"Eating is typically triggered by hunger, which is related to circulating levels of sugars or fatty acids (lipids) in the body," says Schramm. "However, it is well-documented that pheromones trigger a variety of responses, so it's possible they could stimulate feeding or activity."
Indeed, the aquarium and aquaculture markets have for years tinkered with concoctions designed to get fish to eat.
For example, Stimulate "Ultrabite" products containing synthetic pheromones (produced in a joint effort between Britain's Centre for Environment, Fisheries and Aquaculture Sciences and British biotech pioneer Kiotech) were used in Mustad's earlier attractants.
I can attest to Ultrabite's effectiveness. I used it and witnessed its effect on smallmouth bass catch rates on Lake Owasco, one of western New York's legendary Finger Lakes.
It was June of 2005, and I was fishing with bassin' ace Denny Brauer and NAFC friend Chuck Reynolds of Scott Advertising. We were targeting smallies on a deep flat at midday, and the bronzebacks were hesitant to say the least.
We fished identical tubes, side-by-side, in exactly the same manner, and the baits spiced up with Ultrabite invariably got hit far more often. I'm no scientist, so I can't say pheromones made the difference. But something did.
Then, last summer, I was involved in hands-on, controlled tests of doctored vs. undoctored baits for Pacific salmon and halibut on the Gulf of Alaska.
Mustad and Cabela's had invited a handful of fishing writers, including longtime North American Fisherman contributors Keith "Catfish" Sutton, Keith Jackson and myself, to the Last Frontier. We were there to research story lines and put the companies' gear to the test; Ultrabite attractants were on the hit list.
In a nutshell, we fished a variety of presentations ranging from giant plastic curlytails to chunks of cut salmon next to each other (doctored jig vs. plain; doctored cutbait vs. plain). Net result? Baits sprayed with Ultrabite got hit five times more often than undoctored presentations.
If you can imagine grown men jockeying for position to fish the doctored baits, on the pitching deck of the CrackerJack Voyager somewhere on the vast, rolling Gulf of Alaska, you can begin to appreciate how much of an edge it gave us over the fish.
"Mustad's new Activate attractants are even more effective," Funk says. He admits fish pheromones are a big part of the formula but declines to elaborate. "If I told you more, I'd have to kill you," he grins.
As potent as pheromones can be in affecting fish behavior, there's a time and place for incorporating them into your repertoire. Buzzbaits, for example, are pretty much a no-go for pheromones.
"We've found Activate takes a few minutes to trigger fish behavior, so it works best with slow- to medium-speed presentations," says Funk.
"When we first started field testing it, we got conflicting reports," he explains. "Kevin VanDam saw no benefit, while Denny Brauer reported catching more bass on doctored baits.
"This seemed strange until we realized that Kevin was fishing his run-and-gun approach, quickly fancasting spots then moving on. Denny was slowly picking apart cover and structure with jigs."
After using pheromone attractants on slower presentations, VanDam quickly converted. "I believe in it 100 percent," he says. "If I see a fish and have Activate on the boat, I'll catch that fish every time."
Beyond spicing up lures, Funk says pheromones can liven up natural baits. "When you add Activate Bait Enhancer to a baitwell, for example, the baitfish get livelier, which helps them stand out once you put them on the hook.
"Also, some of our charter captains are reporting the Bait Enhancer works like a chum slick," he adds. "As the baitwell pump circulates it into the water, the pheromones and scent attract baitfish and predators to the boat."
Just another example of how phero-mones can affect fishing success, and why anglers everywhere should factor this ancient communication into their Space Age fishing strategies.