Smallmouth senses

Let's talk a bit about a bass's senses and how they view the world. All of a bass's senses are radically different from our own. For example take a bass's ability to see motion. It may be that motion may be the biggest driver of a bass's predatory instincts. The average motion picture plays at 24 frames per second. To us this fuses together into one continuous moving picture. But a bass can see motion so well that to a bass a movie would still be a series of one successive image after another even if the movie was playing twice as fast! Learning this has caused me to rethink things like the idea of painted spinner blades on lures. I've always thought, boy those are pretty but they are spinning so who cares. Well now I'm wondering about just how a bass sees a blade with an ultra realistic baitfish painted on it. I'm guessing the bass sees a flash of the fish, then off, then back again. I'll be picking up some painted blades and experimenting with them this year for sure.   A bass is the ultimate motion detector, to a bass something has to move to be alive. And this amazing ability works even in extremely low light levels. A bass it is thought can detect motion at a hundredth of the light level needed for a human to do so and can find food using even faint starlight.
In contrast most small prey fish are wired more like humans, that is with lots of cones for seeing lots of  color. Which means in the middle of the day minnows have an advantage and probably see the bass better than the bass see them. But come low light the pendulum swings to the bass's advantage. A bass has an eye loaded with rods for low light acuity. Which is why bass become more active and feed early and late in the day. It's thought that bass see reds and greens very well but not so much things in the blue end of the spectrum. In experiments bass often confused blues and purples with various shades of grey and intense blues with black. It could be that a grey plastic worm might be just as effective as a purple one! In other experiments it seems bigger older bass actually see better than younger bass. That bass can recognize smaller objects and see them farther away as they age. A bass has large round eyes set on the sides of it's head and can see everywhere but directly behind and below it. The ability to see prey or potential danger from almost any direction is a tremendous advantage But to really focus on something it must turn and face the object so the two eyes can work together in binocular vision.

The sense of a bass that most amazes me, that I find almost magical is the use of the incredible lateral line. Water is full of waves, not just on the surface where we see them, but everywhere, these waves are caused by anything that moves in the water.  The lateral line system is the fish's way of detecting these waves. Lateral lines are what enable schools of fish to move together so effortlessly. Lateral lines also enable fish to sense and not run into things they cannot even see such as the glass in an aquarium. And in the case of predators like bass they help the bass detect prey. The lateral line seems very adept at detecting the subtle movements of small prey fish located some distance away. Every description of how a lateral line works I've read gets really complicated and hard to understand. It seems that hairlike bundles rooted in liquid filled follicles sense minute changes in water pressure. Plus more of these hairs are located in the liquid filled canal of the lateral line itself.  The bass feels out distant objects by interpreting how they disrupt the intervening water then uses it's vision to decide whether or not to strike in most cases. A bass can even tell how big something is by how much water it displaces! And in one of what is probably it's most important functions, the lateral line can sense the flow of current. The longer the lateral line the more sensitive it is. In essence, a longer line helps the fish receive signals spread out over a bigger area and thus triangulate or pinpoint the direction better the signal is coming from. Time and time again you will find in this article references to the advantage bigger bass have over smaller fish. Many primitive fishes like sharks and rays use a special addition to their lateral line called the ampullae of lorenzini. The ampullae of lorenzini allows them to actually sense the electrical impulses of the muscles firing in prey animals. The only freshwater fish that posses similar powers are sturgeon and paddlefish. All fish possess these ampullae of lorenzini but it's thought they are remnants of having the same ancient ancestors as sharks and rays and they have lost the power of electroreception. Some sources claim that all fish are sensitive to weak electrical charges and even market gadgets to "clean" the current flowing thru your boats electronics. But it hasn't been proven that most fish are sensitive to weak electrical currents.

 And in concert with the lateral line a bass also has an inner ear which it uses along with it's swim bladder to hear sound. Sound travels extremely well under water, something like five times the rate it does in air. So not only can a fish feel a crankbait coming in muddy water it can also hear it. Bass are also able to sort out complex sounds by pitch, tone, and pattern. Much like a person's ability to recognize the notes and rhythms played by a musical instrument, and to recognize the individual instruments even if they are playing the same note and rhythm. In other words pick one minnow out of the school or the sounds of one crawdad crawling on the rocks in a noisy riffle.  Bass combine signals from the inner ear, the swim bladder and the lateral line to form an overall summary of a object in the water. Though a bass relies most on its vision, even blind bass are able to forage and feed because of the almost magical powers of their lateral line and hearing working together.

A smallmouth bass has two pair of nostrils called nares on each side of it's head.  Some researchers believe that a bass’s sense of smell is a thousand times stronger than a dog’s! While the smell of injured prey does induce an instinctual response to feed, the smallmouth’s  sense of smell often serves more important functions outside of catching dinner.  It's thought a bass's sense of smell  is the primary way that this fish avoids conditions in the environment that may be harmful. Things like high or low pH, low dissolved oxygen content, or even the gasoline from the boat motor you got on your plastic worm handling when it.  Some theories suggest that intra-species communication, or the way by which smallmouth “talk” to each other, takes place by each individual giving off distinct odors called pheremones.  In other words, bass know each other by smell rather than name, and communicate with each other by these smells. Male and female smallmouth probably use smell to cue each other to make whoopee at spawning time. Like it's eye sight a smallmouths sense of smell gets better with age also. A membrane called the olfactory epithelium, consists of complex folds that line the nostrils. It's thought bigger fish smell better than smaller fish.  A 6 inch bass have 5 or 6 folds in it's olfactory passages. A 12 inch bass may have 10 folds. While that trophy 20 inch smallie may have as many as 20 folds.   I think there is no doubt that scent could at times makes a big difference in your catch rate. Hand in hand with this, a bass has a good sense of taste and that "scent" you put on your bait may have a taste that makes a bass hold on to your lure just a bit longer.