Bass Biology
By Paul Reinbold
Wouldn’t it be nice if we could understand every thought that goes through abass’ brain. Especially the bass that we are trying to catch at a Bass Bandit tournament or on a leisurely day on our favorite lake. Well, hopefully this article will give you a fewhelpful hints on how a bass from your favoritelake lives it’s daily life.
A bass’ behavior is always changing. There are many things that happen on any given day that dictate what the bass are doing, or what type of mood that they are in. The most important factor that dictates a bass’ behavior is WEATHER! Bass are very sensitive to changes in weather such as a cold front, wind shifting direction, rising and falling barometric pressure. Largemouth bass are more influenced by environmental changes than any other fish species. Nearly everything that happens in the air and in the water has an effect on bass. Probably the most important factor in weather change is the barometric pressure factor. It is a well known fact that a minor barometric pressure change will affect the bass’ swim bladder. This air filled sac is to a fish what an inner ear is to a human. When barometric pressure rises quickly, it exerts pressure upon the bladder, thus affecting the bass’ equilibrium, making it hard for the bass to maintainperfect balance. This greatly affects the bass’ behavior and appetite.
FACT: Shallow water bass are affected by barometric pressure more than deeper water bass!
Keep in mind that barometric pressure doesn’t change dramatically during a period of hours, unless a major storm is moving your way. Bass and other fish have the ability to predict weather better than the weather channel itself. They know when and how long it will last. Blue bird sky days normally prevail after a front has passed through. This is the type of day when the pressure goes up and up. Bass either move down or move into thick cover with “lockjaw” (except for terry’s frog!) The direction of the wind DOES NOT AFFECT fishing. But is does deal with fronts. A strong brisk north or east wind generally means a fast weather change, therefore a drastic change in barometric pressure. A gusty south or west wind usually indicates a slow change in weather, thus minor change in BP (barometric pressure). So it’s not really that the wind affects fish BEHAVIOR. Instead its BP that affects the wind, and therefore, fish behavior. (Yes, you can argue about wind blown points, and shorelines get fish feeding but that’s not what were focusing on here, it’s what causes these changes and types of behavior. Two completely different subjects, even though the go together down the line.) The best days of fishing usually happen after a few days of normal pressure that is interrupted by an approaching front that caused the pressure to fall fast (10-15 points) in a few hours of time. These periods don’t last long, but bass go on a feeding frenzy. The next best days to fish would be a couple of days after the front has passed, this is especially true during the winter months. Or when the wind switches back to the south or west, which dictates the pressure slowly settling to normal.
Ok, lets switch gears here, lets talk about where a bass’ spends most of it’s life. Yup! You guessed it, in the water! But where? Researchers know that bass spend most of their time in deeper water. Especially deeper water that is close to a drop off or ledge, or deep water that has cover and structure on it. Why? Its because it provides them with everything they need, protection and food. Bass who live near drop off’s or ledges have the convenience of shallow water nearby to feed, and then a quick escape to the deep for protection. That is the reason why, when a you hook a big bass, they try their hardest to head out to deeper water if its available. If it’s not then they will try to head to cover and burry in it. That’s why protection for a bass is just as important as food , and deep water with cover nearby maybe the best situation for anglers.
FACT: Do bass have a home range? (meaning; when a bass moves into an area do they occupy that same relative place repeatedly?) Studies show that they do stay in the area. The bass that were studied stayed within 300 yards of the shoreline. Some bass were recaptured 3 and 4 times, yet were always in the same area.
Now let’s get on the subject of a bass’ diet. A bass’ diet varies, but they will often become very selective and will specialize for feeding efficiency. An example would be, if a lake is loaded with 3 inch shad the bass may prefer to feed on these-ignoring other foods in the process-except for one creature. The crawfish! Crawfish are the most prevalent forage found in our lakes and ponds. Bass feeding on them grow much faster than those that don’t live in lakes where crawfish are abundant. Another reason is that crawfish are much more easier to catch, therefore the bass expends less energy and gain the high protein that these little creatures provide. When bass switch gears and go for baitfish such as shad, and minnows they don’t swim up into a school baitfish and open their big ol’ bucket mouth and swallow the whole school. When a bass feeds on them, a bass must isolate a specific victim and pursue it for best results. At the same time a bass is more prone to strike or select prey that is injured or looks different.
FACT: Do bass key in on the eyes of their prey when they strike? Yes! Very strongly they do. In fact over the years baitfish have evolved a spot on their tail that mimics a fake eye. This causes predators to miss their prey more often than baitfish without a spot on the tail.
Paul Reinbold
Badlands Bass Bandits President