Updated on April 4, 2022
The short answer is yes—fish have a sense of smell and taste. But, how sharp and how precise these senses are depend on the fish. For example, catfish have 150 or more folds in their nostrils, giving them a very accurate sense of smell, while largemouth bass only have eight to thirteen, giving them a less developed sense. With that established, let’s dive a little deeper and answer some other common questions about these senses, fish attractants, and bait.
In general, fish can only smell single compound molecules that are water soluble. Every type of prey they might come across has its own unique smell that they automatically recognize as food. The variety of scents a fish can smell is almost endless, but they all fall into only a handful of behavioral responses. Depending on the fish, these pheromone and scent responses are threat, food, migration, and possibly even spawning.
Bass can taste four major categories which are sweet, sour, salt, and bitter. While bass have thousands of taste buds, catfish have significantly more. At only six inches long, a young catfish has more than 250,000 taste buds. Fish can taste things in a similar way to smell, which only includes single compounds that are water soluble. It’s important to know that fish are swimming through water that is full of these compounds, so they use both of these senses together to find food.
Over the years there’s been a number of crazy things recommended by anglers that supposedly attract fish, including salty soft plastics, oily garlic spray, and even WD-40. Looking back at how fish smell and taste, only the salty bait would likely be detected. Fortunately, bait companies are continuing their research and continue to develop new baits with flavors and smells that are designed to catch more fish. So, do fish attractants work? Yes, but only some of them.
While anglers targeting catfish firmly believe in stink bait, the smell you get from bait with a strong odor is what you are detecting through the air not in the water. In the water, these oily and stinky baits are missing their signature stench because many of the compounds are undetectable.
While this was written with largemouth bass and catfish as the primary examples, most predatory fish have a similar range of smell and taste. Understanding how fish use these senses can help you catch more fish and also avoid using baits that won’t work. If you use scented or flavored baits, stick to attractants that fall within the detectable range.