BASS's HEARING
A Bass's Sense of Hearing
In water, sound is transmitted as waves of changing water pressure. Thus, a perfectly silent step on the bottom of a carpeted boat can make a sound (a pressure wave) that is "heard" by a bass.
On the other hand, sounds made by striking the boat are transmitted extremely efficiently into the water and often spook fish, even quiet events that go unnoticed by boat occupants.
A bass can hear both gas powered motors & trolling motors. When they are feeding shallow they tend to spook off a big motor more so than a trolling motor.
Trolling motors do not spook bass, but they can certainly hear them.
The bass's inner ear is a spherical cavity with a ball suspended in liquid, in the middle of the sphere. The ball is held in the middle by sound sensing nerves and tissue. The two inner ears are buried under the skull on each side of the fish's head.
Bass are attracted by some sounds and repelled by others. A few years ago it was discovered that rattles in baits call attention to the bait and increases the odds that a bass will bite.
Among fish in general their keenest sense is the sense of smell. Some fish make much use of their sense of smell while others do not.
A bass has two nostrils, one on each side of its snout and water is filtered through these nostrils and over odor sensing nerve endings. Once an odor has been detected a bass can use its stereo equipped nostrils to zero in on its source, much as it can use lateral lines to zero in on an object making a sound.
Like sounds, some odors attract bass and some odors repel. As a fisherman, you need to know which is which.
The temperature of a bass's circulatory system is not 98.6 degrees. Bass are not warm blooded creatures. Always their body temperature will be the same as the water temperature.
Bass prefer water temperatures in the low 70s. When the temperature is below 60 degrees bass instinctively seek the warmest water they can find.
A sudden drop in water temperature cause bass to go into temporary shock and they quit eating. The converse is not true, however. A sudden rise in water temperature may, or may not, effect the fishing, depending on other factors.
In the early spring we fish in the warmest water we can find. This will be in shallow, northwestern coves, or along rocky northern shores.
Your boat is constantly acting as an underwater, sound transmitting antenna, and it is amazing how well a bass can hear what is going on in a boat.
Much to our benefit, not all the things bass hear spook them.
Bass hear through four separate organs, two inner ears and two lateral lines. A bass's sense of hearing is much better than man's, and water transmits sounds five times better than does air. Never doubt that a bass can hear the noises you make in your boat. But we need to differentiate between two entirely different types of fisherman sound.
Two fishermen talking are making sounds in the air that might bother other fisherman, but their talk will not bother the bass.
Why? because air sounds are poorly coupled into water through the air/water interface. Sounds that occur entirely in the air seldom spook fish.
Digging around in a tackle box, opening and closing rod box lids, dropping pliers on the floor, and the like, are all sounds that alert bass to your presence.
These are also sounds that may or may not spook the fish depending on how deep they are, how wary they are and what types of sounds they have become accustomed to.
The shallower the fish, the more apt they are to spook from a sound. A lot of fishermen catch fewer shallow bass than they should because of noises made in the boat.
Therefore, when approaching a shallow fishing area, you should shut down the big motor about 100 feet from your fishing spot. Then get organized; do all the digging that needs to be done in tackle or rod boxes. And finally when you are ready to be quiet and start fishing use a low setting on the trolling motor to close the final 100 feet.
And pressured bass have learned that trolling motor sounds mean there are fishermen nearby. Experience has taught us that a trolling motor does not spook a bass, but more recently we have learned that trolling motors tend to alert the bass to our presence. Therefore we try to keep our trolling motors on lows and we pulse them as little as possible.
Sounds are efficiently transmitted through the water, through the skin then through muscle anal bone to these inner ears.
In addition, bass inner ears are augmented by lateral lines that are used to hear lower frequency sounds. There is a lateral line on each side of the bass, and each consists of a series of nerve cells that run the length of the fish.
The right side of the bass senses a sound wave at a different time than the left side. Additionally, small differences exist in signal strength and arrival time, as a sound wave strikes various lateral line sensors.
Thus lateral line nerve endings give bass an extremely accurate sense of direction. At short ranges a bass knows exactly were a sound is coming from and whether it sounds like something edible.
Few fishermen finally appreciate the importance of a lure's sound to whether a bass strikes it or not. We think that bass make bite/no bite decisions primarily based on sight, but they will still reject a lure if it does not sound right.
Because of this phenomena more and more baits have built in rattles, and a lot of fishermen are putting rattles in their plastic worms, in their spinnerbaits, and they are also attaching rattles to jigs.
More recently, a few professional fishermen have decided that rattles are being overused. These fishermen suspect that some bass have learned that rattling sounds means artificial lures that should not be eaten.
We aren't convinced that this phenomenon has occurred, but we believe it will in due time.
A Bass’s Sense of Smell
A catfish feeds with its sense of smell. Salmon avoid sea lions and otters with their sense of smell, and they use an acute sense of smell to return to their breeding grounds. Other fish make little use of their sense of smell.
Gas and oil presents an odor that repel bass and it is easy to contaminate a jig and pig or a plastic worm with gas or oil on the floor of a boat or on your hands.
If you have been handling something (such as sunscreen) that might impart a strange odor to your bait you should wash your hands before continuing to fish.
Experienced fishermen carry a small bar of soap in their tackle box for just this purpose.
An injured bass puts out an odor that alarms other bass. Thankfully, being hooked in the mouth does not trigger this odors but an injury to the gills most assuredly does.
Therefore, it is appropriate to release a bass that was previously hooked in the mouth, but it is best that you keep injured bass in your boat until you are ready to leave the area.
Baitfish all have odors that attract bass, and a wounded baitfish puts off an odor that is particularly attractive.
For this reason people fishing with live minnows are well advised to clip the minnow slightly with a nail clipper. Some accept the effectiveness of adding fish attractant to worms, jigs and pigs, grubs, and the likes.
Fish are attracted to the bait through smell as well as sound and appearance. Smell helps induce a strike, and it causes fish to hold onto the bait longer.
The down side, of course, is the slimy stuff messes up your hands, the boat, makes knots harder to tie, and is generally a pain in the butt.
It is a trade off, but most serious bass fishermen routinely use fish attractants.THE INFLUENCE OF WATER TEMPERATURE ON BASS BEHAVIOR
This is a big deal to bass fishermen, because water temperature can be used to accurately predict how bass will be acting at any stage of a year.
Because a bass's entire metabolism is tuned to its circulatory system temperature. In cold water the metabolism slows down, the brain slows down, and the bass slows down.
In cold water a bass's instincts are less finely tuned it has less appetite and it mostly stays suspended in a hiding place, waiting for warmer water.
It is fairly easy to catch bass in cold water, but only if you can find them and if you use the right techniques.
Primarily, this means putting bait in front of a fish that looks right, makes the right sounds, and smells right. The colder the water, the slower the bass's brain operates and the slower you must present the lure, otherwise, the lure is gone before the bass's brain tells it to bite.
When the water temperature is above 85 degrees the bass instinctively seek the coolest water.
But there is a major caveat: other water conditions must also be acceptable In other words, bass instinctively seek out water temperatures in the lower 70s, but only if (1) the Ph chemistry is right, (2) there is sufficient oxygen in the water, (3) if there is food in the area, and (4) if there is cover for the bass to hide in.
Early in the year a bass fisherman seeks out the warmest water he can find that contains these four conditions. During the summer this same fisherman seeks the coolest water he can find that satisfies these conditions.
In the spring rising temperatures are precursors to the bass becoming much more active. The most fun time on a lake is when the water temperature is in the mid to high 50s and the bass are in their pre spawn feeding mode.
We then follow pre spawn conditions for the next month as the best fishing areas move from the northwest part of the lake, gradually around the lake's perimeter until it reaches the lake's southeast coves.
It is the deeper southeastern coves that develop pre spawn prime fishing conditions last. By the time the bass have begun to spawn in southeastern coves, the bass in the northwest part of the lake are in a post spawn feeding frenzy and this is where we fish.
Please note, that there is sufficient pre spawn and post spawn fishing available in the spring that we never fish for bedding fish. The availability of future good fishing suggests that you shouldn't either.