For many years professional and avid sport fishermen have debated the use of scents and fish attractants for successful fishing with verified studies showing some incredible results on just how powerful a fish’s built-in senses used for survival are. Most species of fish develop a strong sense of sight and have lateral lines for picking up vibration and sound but Can fish smell underwater?
Yes-fish can detect odorous molecules in H2O. Like humans, their sense of smell is achieved by olfactory sensory neurons present in their nostrils. Biologists have discovered that fish have an extraordinary sense of smell about 400 x’s stronger than a bloodhound & up 1000 x’s stronger than a human.
For many years professional sport fishermen have debated the use of scents for fish attractants when fishing. That still is the subject of debate but the fact that fish have the acute ability to smell is not. Through various studies on the subject, results show that most fish’s olfactory system allows them to detect very light odors, and for some species from very far away. For example, sharks can smell blood from several hundred meters away.
Can Fish Smell
Fish have two openings (nostrils) on their head that contain an organ called an olfactory rosette that they use to smell. The larger this organ is, the more sensitive the fish is to the odors in the water. In addition, fish have taste buds in their mouths, on their tongues, and in some cases outside their mouths. This combination of smell and taste organs allows fish to find food as well as avoid danger or repel certain scents that are unnatural to them.
Smells are transmitted to the fish by the water surrounding the fish.
Some fish (such as sharks, rays, eels, croaker, drum, and salmon) have developed an incredible sense of smell and can detect chemical levels as low as 1 part per billion. That means fish can detect 1/200th of a drop of a substance in 100 gallons of water. Fish use their sense of smell to find food, avoid predators, identify each other, spot safe habitats, and even locate spawning grounds. If the chemicals signal food, the fish will pursue the food. Or if the chemicals signal danger, it’ll flee. But fish use chemical cues in all sorts of ways.
A fish’s ability to detect the wrong or unnatural taste and smell can affect your ability to catch fish. If your bait has traces of human scent, gasoline, oil, sunblock, insect repellent, rust, mold, or even your aftershave and cigarettes on it, a fish might avoid it, or what is called Repel fish.
In the same way that you would not eat something which smelled or tasted wrong, a fish will not eat bait that has the wrong smell or taste. Other smells help attract fish that has created a market for fresh and saltwater fishing Attractants for game fish like Bass and Trout.
When fish are hungry and aggressive, they’ll hit the bait first and ask questions later. There you’re dealing with how long they’ll hang onto the bait. But when fish are negatively inclined to bite or picky that’s when you have to pay attention to details. That’s when you want to make sure you’re not presenting any negatives to the fish. Having a great sense of smell also helps fish find a mate, detect predators and find fish they’re related to
What Scents Attract Fish
Scents that attract fish are also known as Positive Scents or Scent Tracks. They are a trail of odor molecules that fish give off whether they are swimming or hiding or fresh dead. These scent tracks let predators track down hidden or far away prey items to eat.
According to most anglers, they use scent on soft baits mainly Shad, Crawfish, and minnow Natural scents because of it being a favorite Largemouth food along with salt, anise, garlic, or for its uses in hiding human contact and chemical scents from manufacturing. Other fish like milk products like cheese.
If you decide to use Scents for fishing remember that the scents that utilize fish oil as a base stay on the bait quite well and disperse readily in the water leaving a “scent trail”. Baits that have the scents “built-in” like Yum, or Gulp baits work very well and Scents you apply or spray on bait or lure like Smelly Jelly.
- fish slime
- fish guts
- fish extracts
- human saliva
What Scents Repel Fish
Scents that repel fish are also known as Negative Scents. Any kind of chemical that would be unnatural to a fish-like, gasoline, tobacco, or aftershave that may end up on a lure or bait by making contact with the hook set. Others are:
- human skin oils
- bug sprays
- sunscreens scented or not
- perfumed soaps-baby wipes
- any petroleum distillates like gasoline, marine grease, oil, or diesel fuel.
Can Fish Smell Human Scent
Since we established how sensitive a fish’s ability to smell is and the Negative and Positive scents that have a bearing on most fish reactions then there is not much doubt that a fish can smell a human when fishing. This is a great video on how to take human scent when fishing out of the equation.
You can decrease your chances of offending a fish with Negative odors by simply washing your hands before handling your bait and lures. Avoid deodorant soaps since they have perfume in them. Ivory Soap is a commonly recommended soap. Also, try natural ways of disguising your human odors. This is a great video on how to take human scent when fishing out of the equation.
A fish’s ability to detect the wrong or unnatural taste and smell can affect your ability to catch fish. If your bait has traces of human scent, gasoline, oil, sunblock, insect repellent, rust, mold, or even your aftershave and cigarettes on it, a fish might avoid it. In the same way that you would not eat something which smelled or tasted wrong, a fish will not eat bait that has the wrong smell or taste.
Bass Resource-Scents and Attractants: Do They Work?
Fishing Advisor-Can Fish Smell Odors?