Author: Eric P. Remian – Editor, Tips and Techniques

Photos: Greg Greene – Club Photographer

Subject: ENVIRONMENTAL INFLUENCES - PART ONE

The largemouth bass (Micropterus salmoides) has evolved into a short stocky predator fish primarily because of its instinct to ambush prey in and around various types of cover or bottom structure. It will not and cannot sustain long periods of speed. It is built for short bursts of speed to capture its prey when near its location.

The bass’s location and behavior is dependent on the particular environment in which it inhabits. Anglers need to understand how environmental influences affect the fish and how to utilize this knowledge to become more successful in our never ending pursuant of the largemouth bass.

The following will hopefully provide some insight on the subject as well as some general rules to utilize while on the water.

Ecology of the Environment

The ecology of the environment, most importantly the food chain, governs the life within a fishery, just as forage species adapt to swim in schools for safety, the largemouth bass will find its niche within the chain of life. In a fishery where a higher food chain predator exists such as a pike, walleye or musky, the bass will adapt and limit its range within the fishery. The bass must stay hidden in cover, use the inside edge more so than the outside edge of vegetation or only be found in areas not occupied by the other predator. Those that are foolish don’t grow to pass on their genes. Survival of the fittest is the name of the game.

Where and when the bass is the top predator gives them the best opportunity to utilize their environment to maximum efficiency. In most southern fisheries it will grow larger and quicker because each year of life provides a longer period of higher metabolism utilizing a larger home range which increases its protein intake since it isn’t forced to live in less than optimum habitat. A larger forage base is available for a longer period as well. Most large bass are sedentary, preferring to ambush prey from one location. They will position themselves in the most productive feeding station or location.

It is wise to learn the food chain within a fishery in order to understand how and where the predators are located within the environment you have chosen to fish so that you can concentrate in the most productive areas occupied by the bass.

The classification system of lakes and rivers is important for an angler to understand in order to quickly locate and target fish using the most appropriate bait or lure for success. When the angler understands the physical and chemical composition of the environment, they will better understand the habits of the fish within the fishery. This knowledge provides a better understanding of the forage available to the bass as well.

This subject is a complete article in itself. I will not attempt to get specific other than provide one example of how using general knowledge about a lake classification type can influence the ecology of the environment. Example, a Mesotrophic and/or Oligotrophic body of water would be one that I personally would fish with a jig or crayfish type lures. These lakes tend to be rocky and many have limestone within the bottom composition. Limestone increases the ph of water making it more alkaline. This is important since scientists have determined that where crayfish inhabit an alkaline environment, they will molt more often than those that inhabit a more acidic environment. Studies have been performed to prove that bass will target crayfish 80% of the time while they are in a soft-shell phase after they molt.

Predator – Prey Relationships

Forage must be available within an area if bass are to be present. We have all heard that the bass will be where the bait is. The bass will make movements within a fishery in order to maintain contact with its food source. For example, most guys know that late spring is a very productive time of year to catch bass suspended in tree tops at Little Seneca Lake. If you haven’t noticed that is where the pods of fry end up in their pursuit of free swimming plankton. When the bait gets big enough it will switch its forage to invertebrates thus move to become more structure oriented while utilizing the vegetation for cover. The bass follow and will be more numerous in the grass towards the end of the spring season. This usually occurs at the end of June at Little Seneca.

Most of the larger reservoirs and river systems have huge forage populations. The forage migrates and the bass follow. Shiners and other similar forage species will spawn in the fall. They will migrate up into the back of creeks in reservoirs and/or to the mouths of creeks in river systems. Knowing this will put you on fish at times. The conditions must be right and you must be in an active tributary. Not all tributaries will be active. Some have less favorable water flow, bottom composition and/or oxygen content.

The shad is a pelagic species that roams throughout the lake. When the surface water temperature gets colder shad will go deeper seeking the warmer water. This is one reason why bass are typically located deep in the winter. When the temperature goes below 45 degrees shad start to die and bass will be bunched up near or below them waiting for the fall out. This is one reason why blade baits are so successful in the winter. Knowing what the forage is doing when, where and why will give you a better opportunity for success.

Crayfish, in any environment, are preferred forage of large bass, fish over 2½ lbs. As bass grow and age they become more specialized in their dining habits and seem to know that the crayfish is highly nutritious and is able to be captured expending less energy than would be used chasing a baitfish such as shad. There are more than 100 species of crayfish on the North American Continent. Colorations vary widely due to the unique chemistry of the water they inhabit with different shades of brown, olive, dark green and even black. All have a tinge of orange or red highlighting the sides of their body and edge of the front pincers. Find out the color phase in the fishery you fish and use a similar color. Your success will increase.

According to biologists, crayfish usually live three to five years. They will mate an average of eight times throughout their life. The majority of a lakes crayfish population will be found in depths shallower than twenty feet. Crayfish like very high oxygen levels, which means that they will often be found in greatest abundance on windswept banks

Light Intensity

The movements or migrations that bass make can further be explained as a result of light intensity. Just as humans need food, shelter and water to survive, a bass requires food, shelter and a place to reproduce. When bass are threatened or inactive, they will retreat to a sanctuary, most often an area with low light intensity where they feel safe. Deeper water is guaranteed to have low light levels so larger fish head for deep water since they are not as likely the target of other predators. This sets up daily migrations between sanctuaries and feeding areas. Most migrations occur from shallow to deep in the morning and from deep to shallow in the evening but can occur at any time of the day or night. Knowing the location of different structural elements in deep, mid-depth and shallow water can provide a means to check the status of the migration since for reasons unknown most bass within a fishery tend to migrate at approximately the same time. The structural elements are better known as staging areas which the bass stop at during their travel. If you find fish shallow then other areas will have fish shallow. When the shallow fish turn off, go to that next deeper staging area and chances are the fish can be relocated. It’s funny until they understand how fish migrate; some guys actually beat the shallows to death when in fact they should fish deeper structure. I know, I’ve been there and done that. When using a fish finder, you may have previously marked fish on a drop or at a particular depth one day only to come back to that spot later that day or on another day to find nothing. Don’t assume the fish vacated the area if you don’t mark fish. It could very well be that the fish you marked were inactive and are now actively feeding up on the point, on the side of a point or on a flat close by your location thus they are not visible to your electronics. Move shallower and/or fan cast the area to contact the active fish.

Bass can see at about 0.1 percent of surface light. Most baitfish species do not have similar sight capabilities. A bass instinctively uses its sight in low light as an advantage when feeding. The turbidity (amount of suspended particulates) of the water will affect the depth of the sanctuary since it will block the light from penetrating the water. This is why when the water gets muddy or becomes stained bass will relocate higher within the water since they still need to see. Their migrations won’t be as far either since bass have a greater sense of security in the lower light level created by the turbid condition even though it could be very shallow. Cover that provides shade will be favored by bass all the time, shallow or deep. Target it.

Humans can see into the water down to a light intensity that’s about 1 percent of full daylight. Scientists use a white Secchi disk to determine the amount of turbidity in water. Fisherman can and should use a white spinner bait. The method is such that the disk is lowered to the point where it disappears, then, the depth is doubled to determine the depth of light penetration. Technically this depth would be at 1 percent of the light intensity at the surface. This depth is also the depth at where vegetation cannot grow any deeper and bass typically retreat to. As stated earlier, bass can see to 0.1 percent of surface light. Multiply the depth determined by the turbidity test by 4. This will be the depth at which bass can see your bait or feed by sight but not necessarily where they will be located.

On your next outing use the test mentioned and then target the depth determined. You will find that most fish that you mark on your electronics will be near the determined depth. Also, spinner bait experts use the depth that the lure disappears as a guide for retrieval speed. The retrieve is slowed enough to keep the bait at this level or just below it. It’s typically the shallowest depth at where the bass are more often positioned within the water column. Understand it and you should be more successful.

I have spent too much time on this one article to keep it simple. Instead of writing so much in one article, I have decided to continue this as a series with other Environmental Influences in a part two article. To be discussed will be water temperature with all its influences to include fall turnover, lake stratification and how the thermo cline affects fish location.

The environment can and always will have a major effect on the largemouth bass. The more you become in tune to it, the greater your reward. As I have always stated in the past, I judge the success out my adventures not only in the number or size of the fish caught but just as important is what I have gained by having the opportunity to just be there soaking it up.

Have fun!