How Well do Fish Smell?

 

A salmon can detect the smell of it's home stream five thousand miles at sea, and follow it home to spawn years later.  This amazing ability allows the salmon to detect very small concentrations of some compounds in the water.  The salmonid family can detect L-serine amino acid in quantities as little as 1 part per 8 billion.   This phenomena will work against fisherpersons as well as for them.   If you understand & take advantage of this information, you will put more fish in the fishbox.

Detrimental Smells : Mammals, humans included, give off a chemical called L-serine where studies have shown do repel fish.  There have been tests done where people with their shoes off & pants rolled up, wade into the raceways of dam fish ladder passages.  In some cases, just this simple experiment, stops the movement of fish into the fish raceway for a period of time.

Also this is why some people just can not seem to catch fish as they give off more L-serine than others do.   I knew twin brothers, one of which could catch fish blindfolded & behind his back, while the other had to really try even to get a bite, this possibly was the situation with them.    So what does that mean to you & I as a fisherperson?  It means that salmon, as well as trout and other game fish, can smell you or any contaminating scent if you may have handled even the lure without gloves. 

Studies have been conducted in fish ladders of dams & have shown that people who give off very little L-serine can stand in the passageway with their shoes off and fish will continue to move through, whereas people who give off lots of the chemical will stop all upstream movement through these passageways.

There are other chemicals that the fish do not particularly like.  Gasoline is one high on this list.  So if you are refueling your gas tank or are connecting your fuel line to your motor and it leaks a bit,  or you check the oil level in your engine, you may need to wash your hands if you want to catch any fish the rest of the day.   One soap that has been used by many guides for years is the dishwashing soap, Lemon Joy.

The smell of onions, potato chips & fried chicken if you get it on your hands when you ate your lunch & then got it on the line, lures etc. will kill a bite.  If this type of food is in your lunchbox, it might well be best to use latex gloves to eat with so the bad scent does not contaminate your lure, line sinkers etc.  Other things that may cut down your angling success include cigarettes, some foods like peppers, some hand lotions, liquids etc. 

Insect repellent is another bad smell, the various insect lotions and sprays are not an attractant, but do act as a repellant to fish.    They can also have a detrimental effect to the finishes some of your gear or lures.   Fisherpersons may find it advisable to carry one of the biodegradable soaps with them and wash their hands often to remove all odors possibly offensive to the fish.

Good Smells :  The above being taken into consideration, it also means that smell, or a scent can be used on a lure as an attractant to help you.  There are companies that make attractants for just this purpose.  These scents do two things; first they mask the L-serine that we all give off, but they can also contain amino acid profiles that appeal to fish to trigger feeding behavior.

One well known fisherman swears that coconut-scented Hawaiian Tropic sunscreen adds to his catch.   Another successful salmon fisherman who is a member of our fishing club, has found that Greatian Formula, Just for Men hair color has improved his catch on the days he darkened his gray hair with it.

Do these scents work?   There has been many side by side tests done and unequivocally it has proven the effectiveness of the scents and attractants.   Ask about any tournament fisherperson, experienced anglers & guides if they use scent.   There are many ways to use these attractants.   Depending on the consistency, if it is a jelly, they you smear it on the lure or flasher that is being used as an attractor.  Some of these attractants are a liquid & designed to be soaked into a fly or yarn.  There are also capsules that attach to the line that have small holes to slowly dispense the scent.  There is one nylon bag sold by Silver Horde that has hatchery feed pellets inside that is attached to a downrigger ball to leave a scent trail in the lure's path.  This is designed to attract returning hatchery Coho salmon.  

Smelly Jelly makes many scent attractants in different flavors if you will.   Berkley has their PowerBait attractants and jellies.  Other companies seem to pop up locally & are also effective.  These products come in liquid and gel forms, and can be spread on any lure to increase their fish catching potential.   Some lures incorporate scent directly into their softbaits like rubber worms or jig bodies.  The scent in these softbaits encourages fish to not drop the baits soon as they realize it may not be what they thought, giving you a better chance of a hookset.   Berkley has a huge selection of PowerBait for all species, including a new Inshore bait that has proved effective for halibut, and big lingcod.  At times it seems these bait companies are making a product to catch you & I more than the fish. 

Chinook salmon seem to prefer a mix of sardine & garlic scent.

Do They Work? :  Well I can't twist your arm from here, but look at most of the successful guides, some even have a special scent that they very carefully guard it's formula.   Using scent may allow you to catch more and possibly bigger fish.   Also keeping your hands clean, removing offensive odors off your tackle and adding fish attracting smells to your offering will up your odds for better days on the water.   Many fishermen will wear surgical gloves when baiting up & if you seem to not be catching the fish you think you should, then this would be a very simple & possibly rewarding experiment.

Clean Your Lures After Use :  One related thing here is that IF you do use scent on your lures, that it can get rancid over time when not cleaned off after usage.  Some dedicated fishermen discard their scent each year & buy a new supply.   Others make a point of carefully cleaning it off the lure at the end of the day.  Therefore it will behoove you to make a practice to use Lemon Joy & wash off the scent before you put the lure away.

This is my shortest fishing article, but probably one of the most important.

Copyright © 2005-2008 LeeRoy Wisner  All Rights Reserved 

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