Big Indiana Bass

To make a long story short, a tourney friend who spent quite a bit of time fishing in Indiana recently moved to Tennessee. He posted back about what a big difference he’s noticed between TN reservoirs and catch rates versus Indiana reservoirs and catch rates. Indiana of course being much tougher, and so the question posed was why? He threw out a few theories as did several others, and there was the DNR management finger pointing, too. This led to a great discussion of which I wanted to “transcript” my responses here.

OK, the big difference between (Monroe, Patoka, Brookville, Cataract, Raccoon) and (Lemon, Boggs, Geist, Morse, Eagle Creek, Waveland, Glenn Flint)? The former are all flood control and as such, Corp of Engineers and flood control purposes are 1st and foremost on the list. All recreational purposes including management by DNR are secondary.

What about the latter? Non-flood control. They all have simple overflow type dams that keep water levels pretty stable over the course of the year, especially around spawn time. Stable or higher water levels create great LMB spawns and typically high recruitment. This then yields good catches, at least for fish up to keeper length for several years down the road.

Studies on Lake Chickamauga show a pretty good correlation between reservoir retention time and LMB juveniles (recruitment). The more they have to “flush” the system the worse the bass pops tend to be for a given year. The same can be correlated to our big waters. The more our waters are fluctuated in an attempt to keep stable water levels or prevent flooding, the greater the likelihood of a screwed up spawn.

In the big picture, DNR and management have very little to do with the productivity (and subsequent “good” or “bad” fishing) of the lake. That’s just a convenient excuse for anglers to point fingers at for their lack of success. DNR doesn’t control water levels, they have only slight control over angling pressure, they have very little control over habitat, and the tools at their disposal (size and creel limits) are really just for trying to fix a screwed up fishery once it is out of whack. The rest has very little effect on Mother Nature. Like a friend of mine has stated before, “greenies” breed like rabbits when given the right conditions and opportunities. If your lake doesn’t have the right conditions, there is not much the DNR can do about it.

Two good examples are Geist and Morse. IDNR hasn’t done a thing management-wise on those two bodies of water for the past 15+ years due to the exorbitant launch fees. There are no restrictions (permits) on tourneys, no special size limits and no special bag limits. No stocking what-so-ever. Their way of showing displeasure to that whole situation. Yet despite all the pressure mentioned, they’re two of the best lakes in the state for bass. Why? Stable water levels, great shallow water spawning habitat and great shallow water cover, plus limited harvest by “meat” fishermen due to the high launch fees.

Here are two other important points; pressure and conditioning. These things have an effect when you don’t have high bass populations to begin with. If you had high bass populations (good spawns and good recruitment), you’d be catching plenty of fish. For bass up to legal size of 14-15” it has been shown that there is good correlation between number of fish and angler success. Need Indiana examples? Remember Boggs in 2000-2001 (313 bass per hour electrofish rate), Patoka in the early 90’s (175-357/hr), Waveland before the fish kill last year (169/hr), Glenn Flint before the renovation (143/hr), Dogwood (195/hr), Westwood (183/hr). Get the picture? All of these were “numbers” lakes where getting 40-80 bass per day was routine. What is Patoka now...(87/hr). How about the Ohio River Cannelton (5-15/hr). I haven’t tracked down Monroe’s but I was thinking about 70/hr. for the last survey I saw.

So that just means less fish to be caught which makes for tougher fishing. You better figure something out to be able to consistently catch fish on these bodies of water. This ties in with the conditioning. Admit it, how many of you guys “kill them” in practice on Wednesdays and Thursdays? The fish are still there, but conditioning, pressure and traffic have an affect when population levels are low. Fish definitely will change their feeding habits and patterns in response to increased pressure!

Some of the other factors not often considered:

Private waters often get mentioned but they get much less pressure, especially tournament pressure, and less harvest. Boggs...no tournaments allowed through the summer. Lemon...no tournaments allowed on Sundays. Eagle Creek and Dogwood...no big boats due to the 9.9 hp limit, so very little tourney-type pressure. Getting the picture yet? From now through September, every 8-10 hr tourney will kill between 20-30% of the bass weighed in via delayed mortality. Depending upon all the other combined factors discussed, this may or may not make a difference on some waters.

Lastly, a few other things to consider.

- Longer growing seasons to the south.
- Practically no spotted bass in Indiana reservoirs. This makes up a bulk of the catch in some Southern tourneys.
- Most Southern states have a 12” size limit.
- No threadfin shad, bluebacks or alewife in Indiana reservoirs for food, only gizzard shad which can quickly outgrow consumption size.
- High pressure on small surface acres

So while DNR may have some control with your overall “experience” as a tourney angler at a state property, they have very little control over what you’ll actually catch or how good fishing will be. They have to work within the watersheds Mother Nature has given them and the limited authority over properties owned by the Corps. If you watched the All-American last week on the Ohio River out of Louisville, or if you’ve seen the BassMaster Classics from Pittsburgh, Louisville or Cincinnati, then you’ve seen that even the best anglers in the country can’t overcome a crappy fishery. You either have to pick and choose the lakes you fish based on where you can catch lots of fish, or just tough it out with the rest of us on our Indiana bodies of water.

On Reservoir Hydrology:

It really does vary among waterbodies. Maceina studied 4 reservoirs along the Tennessee River (Ky. L, Wheeler, Guntersville, and Chickamauga) and concluded that weak year-classes were produced during wet early-summer conditions after largemouth bass hatched, whereas stronger year-classes were produced during dryer early-summer conditions. This was because wet summers resulted in increased discharge from dams and heavy flushing of the reservoir.

Sammons et al. studied Normandy Reservoir but found that combinations of hydraulic factors (reaching full pool early in spring; maintaining full pool for at least 90 d) allowed largemouth bass in Normandy Reservoir to hatch early and experience rapid growth and good survival. In this case, high water levels were a good thing. Aggus and Elliott (1975) documented that the strongest year-classes in Bull Shoals Lake, Arkansas, were produced in years of high inflow and high summer water levels, too. High summer water levels were also linked to high survival of age-0 largemouth bass in West Point Lake, Alabama–Georgia (Miranda et al. 1984).

So as usual, your results might vary. What appears to be an answer or explanation in Indiana might not be the correct answer in Kentucky or Tennessee. I still think a lot of this has to do with the overall flushing regime for a particular reservoir, along with how high a reservoir is allowed to flood and what cover options are available at a given flood level. It may turn out that flatland type impoundments have a much different requirement than narrower, river-type, rocky impoundments.

There are also definite differences in spawning success under such conditions between spotted bass and largemouth bass that ultimately may make a difference in the fishery. For instance in your neck of the woods, Center Hill tourney catches are usually made up of 70% spotted bass whereas at Percy Priest, 85% of tourney catches are largemouth (Kaintz et al. 2005). Normandy is more split being 60% largemouth and 40% spotted bass. So depending on the prevailing weather patterns, certain reservoirs down that way would probably be much more (or less) affected compared to ours which are almost 100% largemouth weigh-ins.

Whatever the answer, it all makes for some interesting reading.

Back in April I posted about a section on BassFan that was highlighting some of the work of Dr. Keith Jones from Berkley. Dr. Jones has his own book out on largemouth bass entitled "Knowing Bass: The Scientific Approach to Catching More Fish" which can be found at the book link on the left sidebar of this site. The section on BassFan is entitled "Bass Buzz" and seems to be a now somewhat regular column on the site. The most recent article posted today on the site is "Can Bass Learn?".

The article references an Illinois Study, the abstract of which can be found here. One of the interesting findings from that study was the following: "Some fish were caught as many as 16 times in a single season and one individual was caught 20 times during the 4-year experimental period. On the average, largemouth bass were caught approximately twice during any given fishing season. Between 1977 and 1980, the 1,774 fish that were caught in 1980 had been captured a total of 6,969 times or approximately four times each."

They ultimately determined that largemouth capture by anglers is largely a product of individuality and can vary from season to season. They also suggested that this trait could be heritable. Another study with very similar results was written by Willis and Cody. You can find the .pdf version here and an html version here. This study confirms a couple theories, the first being that catch rates of largemouth bass in general are directly correlated to population size. The more fish in a body of water, the more fish get caught. This has been further documented in other species of fish, most notable (that come to mind) being walleye. The other interesting finding they mention (from an INHS study), is that as pressure increases on a given body of water, catch rates ultimately decrease, also directly correlated. They surmized a learned behavior which could actually make bass in a particular body of water practically uncatchable.

Another similar study which documents the genetic differences in catchability between different subspecies of largemouth bass comes from Kleinsasser et al.. They confirmed that northern bass were generally much more "catchable" than their Florida counterparts. They also documented what is known as "hybrid vigor", that being the first generation cross between the two subspecies showed best growth and weight characteristics when compared to either parental lines. This obviously has some limitations though based around environmental conditions, as Florida strain bass when stocked up north tend to do no better than their northern counterparts.

Finally, an interesting study on rainbow trout from Askey et al. subject to heavy catch-and-release angling pressure. Catch rates dropped off significantly within 10 days of angling pressure. Among their conclusions:

• Learned hook avoidance was a key component needed to explain the large data set of individual capture histories.
• It was only possible to fit the sharp initial decline in catch rates if intrinsic differences in fish were also taken into account. It seems plausible that some proportion of fish populations should be less vulnerable to angling because of factors such as highly selective diets.
• Catch rates may continue to decline with continued pressure; however, the decline is much slower after the original “fishdown” period.
• Lastly, a small part of the decline in catch rates was fishery independent; catch rates were found to decline in the lightly fished lakes. Thus, other geographical regions that have different climatic patterns and fish species may experience different seasonal trends.