Pond Boss Forums MANAGING AN EXISTING POND Evaluating and adjusting fish populations Bass Mortaity

Has anyone data on the expected mortaity rate of bass in southern ponds and the affect it would have on raising trophy bass. I guess I'm wondering what are the chances of my first generation Bass surviving to that 7-10 pound class? 50% 75%? Including the affect of catch and release damage to a bass population.

LakeL :

Not sure just what you are looking for. A couple of points. Not all LMB will grow to 7-10# only a % have what it takes (genes, food , luck, time etc.)to get there. Mostly females so that knocks out most all the 50% that are males. A higher % of your first stocked LMB will live to old age assuming they were added into a pond with a good forage base and water quality and no predators larger than them and the water quality and forage stay good. All generations after that have large % losses due to predation by most things in the pond at one time or another along the way. Stress of all kinds, including being caught and released, will reduce the % survival. Summer is the worst time for stress in hot water in the south. There are a number of ways to interpret your question on morts.; as in, if fewer live then the chance of the rest getting big without competition is greater or morts. on the next generations effecting the original stockers. So I will stop here and let you ask about what I have not answered and then I will try again.

One thing is sure, in order to get the normal pond to produce large LMB you will have to harvest LMB unless you intend on constantly stocking additional forage of the right size. If you intend on stocking like that you will have to watch for stress related to carrying capacity and DO problems.

Raising trophy bass is a fun mixture of habitat, food chain, genetics and selective harvest. Trying to understand what percentage of originally stocked fish might survive is more of an exercise of figuring out what it takes to manage the dynamics of a food chain, protecting the largest bass in the population, while delicating promoting adequate recruitment of new bass each year. All the while, you have to pay attention to the food chain of what each size class of predator fish has available at any given moment. It's really fun, and challenging.

How long does it take for a bass grow to trophy size? What's the expected annual mortality of the first bass stockers in a new pond? I don't know. I could guess, but my guesses are no better than anyone else's and not half as good as someone's experience (and there's a LOT of big bass experience at this forum - see the above poster).

But I can do Math. Yearly survival rate = (1 - annual mortality) to the Nth power, where N = year number. So take your best numbers or make your best guesses, and you can get an rough idea what % of fish live how long:

40% annual mortality:
4th year survival = 13.0%
5th year survival = 7.8%
6th year survival = 4.7%
7th year survival = 2.8%
8th year survival = 1.7%
9th year survival = 1.0%
10th year survival = 0.6%

30% annual mortality:
4th year survival = 24.0%
5th year survival = 16.8%
6th year survival = 11.8%
7th year survival = 8.2%
8th year survival = 5.8%
9th year survival = 4.0%
10th year survival = 2.8%

20% annual mortality:
4th year survival = 40.1%
5th year survival = 32.8%
6th year survival = 26.2%
7th year survival = 20.9%
8th year survival = 16.8%
9th year survival = 13.4%
10th year survival = 10.7%

10% annual mortality:
4th year survival = 65.6%
5th year survival = 59.0%
6th year survival = 53.1%
7th year survival = 47.8%
8th year survival = 43.0%
9th year survival = 38.7%
10th year survival = 34.9%

Theo :

Check your email for a copy of the TPWD 17 year study. It has some of the data which you may be able to estimate and put into your equation. The #s are from ponds and from Texas where LakeL's question originated. I think the results would be outstanding. Good thinking!!

While statistically, you are correct, the reality is that bass which live longer have much greater odds of survival. They move from eaten to eater. A six inch bass can eat smaller bass, but can be eaten by a 12 inch bass. But, a 12 inch bass can eat many sizes of bluegill and bass six inches and smaller, but will be eaten by a four pound or larger bass. About the only thing that might eat a four pound bass in a bass lake is Overton's mega-blue cat. So, in a traditional bass/bluegill population, bass survival rates dramatically increase with age. To further complicate things, hopefully more than 95% of newly hatched bass go the way of the buffalo. If more than that survive, managers ultimately deal with overcrowded bass, usually when the babies grow into the 8-14" size class. My experience trying to grow big numbers of trophy bass in a lake is that it is one of those 'says easy, does hard.' A manager basically has two jobs. Job one is to get bass to sixteen and 1/2 inches. That means growing lots of bluegill, threadfin shad, minnows, redear, tilapia...you get the food chain picture. While bass are 'racing' to 16.5", you best be preparing for the next level. Small bass have small bass habits, eating small nuggets of intermediate size bluegill, bass, and any moving morsel which fits into a young bass mouth. But, when bass hit that magic 16.5" mark, their habits quickly change. Big bass have big bass habits. They eat big, they hold tight to cover, they become solitary and defend their area. Small bass are like gang members, pillaging, chasing, bullying their way to the next meal. Growth rates scare me. Read this...you won't hear this from many people. I am as fearful of fast growing bass as I am of slow growers. Here's a story. A good friend of mine, Harrell Arm's, of Proctor, Texas, had a pond under management. He called one day, with the buttons on his vest about to pop. "We electrofished so and so's lake today, shocked up two five pound bass." The lake had just finished its second year. Harrell was proud of his management skills. Honestly, I was a bit jealous, until I thought about it. If those young bass grew so well so fast, what kind of an impact will it have on the entire population, then the entire pond over the next few years? Here's what I thought, and over the next few years, it's exactly what happened. When a few fish are giants early, that means survival rates were low, and food chain nuggets were high. A few bass had all they wanted to eat. A virtual buffet. The next spring, bass spawned like crazy, filling that pond with intermediate bass. I talked with Harrell for several years after that. He spent several days every year, shocking intermediate bass from that lake, just to keep it in balance, and give those trophy bass a fair shot to reach their potential.
Ideally, the entire bass population grows at average rates, with a few above average bass excelling. Those are the fish I want to focus. When we can manage a few bass beyond 16.5 inches, all the way to stardom, things seem to work. We grow giant bass, with some young bass standing in the wings to fill those large shoes when the time comes. Giant bass eat intermediate size bass, assisting the selective harvest process, and the landowner is happy. If we can have five pound bass in the fourth year, then sevens in the fifth, we ultimately have some double-digit monsters in the sixth. It seems to work for us, as long as the pond or lake has the right habitat, food chain, genetics and selective harvest.

When I think back of stocking my first pond, I thought it would be like the saying in the movie "If you build it, they will come". They did but I didn't know how to manage it. They went.

Theo :

I can't get table 3 from the study to copy and paste to this post. That I think would help answer the question at least in part for LakeL. See what you can do.

Thar she blows:

Oh, the things me duz fur me brudder Bloody William Kidd. Arrgh!

Arrrgh Bloody Sam Kidd me be in yer debt fer my ship was a flounderin in da shallows wit no wind.

Bloody William Kidd