July/August PB magazine reports study showed that tilapia rarely ended up in LMB stomachs. Thus, it is easy to conclude that they don't really help the food chain much, and are basically just a way to control algae.

Bob Lusk disagrees. His experience is that TP stocking correlates with improved YOY BG survival, which of course is good for LMB. Fascinating featured article well worth your time!

PS Re the question of whether TP are worth stocking for LMB, it would be interesting to note what happens to LMB & BG numbers & relative weights in ponds where TP are stocked, and compare to ponds where they aren't.

For clarity, tilapia rarely ended up in stomachs of larger bass. They didn't lavage many bass smaller than about 12".

And there is no mail delivery today (4th of July). Can't wait to read the latest issue.

With a caveat for species change, the first year I ever saw fat SMB first thing in the Spring was the year after I first stocked Tilapia. They really pig out in the Fall when the Tilapia get lethargic before dying.

Another factor to consider is that large BG and small LMB may feed on YOY TP. That would not have been picked up in this study. If so, it would explain improved YOY BG survival, as both BG and LMB predation pressure eased.

My personal experience was/is when Tp are stocked into a ponds prior to stocking lmb, the Tp will grow to have many offspring. In fact, my pond had so many Tp they took over the 3 feeders I had and became feeder junkie's, crowing out the Bg for the most part. Tp were everywhere and that was with me starting out with only 5 lbs of 3 to 5" Tp for the whole pond. The next year after having lmb in the pond and stocking Tp with 12 lbs per acre I only had a few Tp at years end or when winter cooled the water down. So, this year I went with 15 lbs per acre of Tp. We will wait and see what comes to the surface this coming Dec. But right now with what I have experienced, I would have to say the lmb controlled the Tp numbers in the pond

I totally agree. Other added forage (eg TFS) has been studied and we a have a good handle of the benefits for LMB and the detriments for BG. In the case of TFS, it is known that they reduce BG biomass but the productivity of the system is improved for LMB.

To me, it seems quite reasonable that TP are an overall benefit to ponds as they are a species that feeds very low on the food chain, are able to utilize primary production of macro-algae, and their biomass is returned to other pond creatures at the end of the season. Even so to propose that BG biomass is improved requires evidence that to date is lacking. There may already be enough anecdotal evidence of improved LMB biomass to expect confirmation in trials.

I think it would be great to see some studies on the LMB/BG/TP interaction to understand how pros and cons may contribute to management goals.

The studies are very inconsistent on this issue with studies going different directions. Some find increased BG biomass due to less predation on early age BG. So while the BG numbers are about the same the size of the BG are larger. BG and TFS only compete for food on a minimal basis - not direct competition overall. In some instances the overall bio mass increased - a shift in the chart to a higher productivity level.

My 2 cents is tilapia work the same way in some cases. It just depends.

I can see that but it would be great to understand what conditions are responsible for the differences. I would suspect that when BG biomass is below carrying capacity due to an overweight LMB forage-limited biomass that BG survival is increased. In that case, BG would benefit because LMB eat the TFS preferentially and the BG use of lower trophic levels was underutilized.

On the other hand, when BG are near carrying capacity, TFS compromise the BG food chain by competing with the creatures that BG eat. In that case, BG would have less food available and their biomass and RW suffer as a consequence.

I too suspect that TFS and TP interactions are similar. Even so, in either case, LMB benefit but for BG ... it depends. I would be very suspicious of any study which might claim that the ultimate BG carrying capacity would be increased by the addition of TFS (or TP for that matter). For anyone with an emphasis on BG, these species are very likely problematic.

I can answer that one. And, just for clarity, I'm talking about what I know and personally experienced here in Hooterville.

I've done the spring/fall TP stocking for the last several years. What has happened with my LMB is that the average relative weight has increased from 80% to 95%. RWs were verified by 2 post spawn electroshockings, and no LMB over 8#'s were factored into the numbers. I also picked the post spawn timing so that I could get a more accurate "walking around" weight of the females, so no egg laden females were weighed either.

My 6-9" CNBG numbers have also exploded to the point I'm culling them. Springtime numbers of 3-4" CNBG have increased also. As of this morning, the 4-6" CNBG (that were 3-4" early this spring) are decimating the LMB beds. One LMB bed with a male guarding it was surrounded by at least 20 CNBG. The bed was extremely silty from the constant attacks, and the LMB just wound up swimming away. For my big pond, this means greatly reduced LMB cull days. My personal experience is that it's far, far easier to add LMB, than to control their numbers once they're skewed to the high side.

Hourly LMB catch rates have dropped slightly, but the pounds caught per hour have stayed fairly consistent. My 2#'s are getting shorter, and I'm very ok with that.

I've also stocked TP in my hatchery pond several times as forage at rates as high as 200#'s per acre. Since they were being eaten daily, there were no biomass problems, nor any floaters when the water temp dropped.

Here's what I've seen with threadfin shad in the private waters we manage. When there's an adequate bloom, threadfins thrive. What most people don't really think about, or understand, is the dynamics imposed by habitat, or the lack of habitat. Where we have bass-crowded lakes, there's typically not enough of the proper habitat for the support species. In other words, there's not enough escape cover for small fish, not enough spawning areas for bluegill, or skewed amounts of habitat that favor small bass. In those lakes, we focus on appropriate habitat, plus a good food chain for bluegills. Keep in mind bluegills, especially in the south, are spawning before threadfin shad. So, that first hatch of bluegills has a decent advantage in the food chain, if they have strong escape cover in the form of plants or something else that's dense. When threadfins spawn, they lay their eggs on grassy substrate, coming in waves before daylight, until just after the sun comes up, then they head to open water. When those babies are hatched, they head toward open water as well, but will see the "safety" of docks and other places where they migrate in and out. I haven't seen a managed lake where the population density of shads suggests a compromise with baby bluegills. What we have seen is an increase in relative weights of intermediate sized bass where threadfins are thriving.
Lots more to this, but there's a few thoughts.
One of the 'problems' with a study to figure this out is just how different every pond is. One of my favorite phrases is "As goes the habitat, so goes what lives in it". I totally believe that. When habitat favors a certain size class of a certain species, that one will thrive...especially if some of that habitat favors what that size class of that species eats. That's why, with my little pond management company, we focus on habitat, first.

Al,

In your particular case, was a RW of 80 post spawn a cause of concern for you that the LMB were forage limited? Or is this RW normal or perhaps above average for post spawn? Could the RW of LMB be an indicator as to how LMB and particularly BG might respond to TP introductions?

Most misunderstand what "carrying capacity" is. That number changes constantly and from season to season. In very general terms, carrying capacity is not for an individual species, but for all biomass in relation to how much total food and O2 is available and how much waste (ammonia, nitrites and nitrates) bacteria and plants can remove. Since Tilapia do not eat foods most any other aquatic creature eats, Tilapia will increase the carrying capacity, often doubling it or more. By eating the "wasted nutrients" (FA and detritus) in a pond, and then becoming prey, most every other species will grow more, larger fish. Tilapia often increase DO levels in a BOW while reducing biomass consuming O2, yet also reduce FA which produces O2
...yet in the end, there will still be a net gain in O2.

As for the study saying Tilapia were not often found in "larger LMB", I'd be interested in knowing what time of year the LMB were looked at...I doubt it was when Tilapia were lethargic. From my many observations in clear waters, Tilapia over 4" inches, in waters above 70 degrees, are extremely difficult for bass to catch. In mid summers, I have watched bass totally ignore schools of edible size Tilapia...I theorize that the LMB learn they are too much work to even try eating them. Once Tilapia become lethargic, I'd lay odds on all sizes of LMB being bloated with Tilapia after a lavage....

With Tilapia present, Tilapia under roughly 4 inches become the primary forage species. This can greatly reduce BG being preyed upon while Tilapia are thriving. Once water temps drop, and Tilapia are decimated by being gorged upon, there will be greater numbers of BG, and more size classes due to the "extra" forage the Tilapia were for the yoy BG.

I can't even begin to estimate how many pounds of forage Tilapia can produce in a season, especially since most are consumed before reaching 4". It may be worth noting that Mozambique and Blue Tilapia (and their hybrids) will reproduce about every 3 weeks, and can go from egg to 1.5 pounds in 6-9 months...Tilapia also grow an inch or more a week till reaching about 6", so they feed a wide size class of predators.

I do recall a polyculture food fish study with catfish and "tilapia" (species not identified)....100 pounds of Tilapia were put into a catfish pond containing 1000 pounds of catfish. No feeding or aeration was done and at harvest 4 months later, there was 1260 pounds of catfish with 20% mortality by numbers and over 1000 pounds of tilapia.

I totally agree with this.



Al, could you describe your management goals in more detail? My impression is that your goals include a creel abundance of 2 to 6 lb LMB with an occasional > than 8 lbs. Is that a fair impression? What would you estimate the LMB biomass needs to be in order to meet the catch rates you are experiencing. What are the catch rates? Your particular method isn't precluding large BG either. You use multiple weapons to achieve goals to include, feeding, annual TP stocking, and supplemental LMB stocking. I would love to see a thread on your management style ... do you have a thread covering your management approach? If not please consider one.

jpsdad, to answer your question more directly...I don't believe there is any other fish that you could stock for less money that would produce even 10% of the pounds of forage fish that can eventually wind up in growing big bass. Tilapia do become pellet hogs if you feed pellets, but if Tilapia bully away BG, the Tilapia still convert feed at a 1.2:1 ratio while BG convert feed at a 4:1 ratio, and those pellets still get into the BG when the BG focus on the Tilapia fry and fingerlings instead of pellets...You will find you BG numbers increased, and growth rates higher than with commercial feed alone...in short, Tilapia are excellent for growing LMB!

JPS, any answers to the questions would be conjecture on my part, but correctly sized and easily accessible forage is probably always a concern on a 20 yo pond where LMB are the alpha predator. What should the post spawn RW of a LMB be in a TX pond be? Are your numbers different than mine?

I'm more of a doer, and not much of a thinker anymore, so I stick with a predetermined plan of attack until there's success or failure. At this point the RW numbers are improving, and recreational fishing hasn't suffered, so I'll just stick with the current plan of culling LMB and adding seasonal tilapia until the results decline, or level out. At that point, I'll need to re-access what other options or scenarios could help my BOW. I will add one thing that limits my overall success is my "do no harm" rule. I will never do or add anything in my BOW that I can't take back. TP are seasonal fish, so any possible downside would be eliminated at the first, but hopefully second, cold snap. If they didn't die, then I would be stuck with a pond full of gizzard shad sized fish that eat algae. That could certainly be a oopsy here at my place.

It all depends...

Thank you, but John (snrub) would have to be the ghost writer.

Interesting, Tracy. I had 150 lb of TP put in back in May and haven't seen any around the dock feeder since then. I'm sure they are still around somewhere, but something is keeping their numbers in check -- or maybe they are frightened of all the hungry 2 to 4 lb LMB which hang around the dock.

With regard to species specific carrying capacity, I am thinking of species biomass limitations with regard to forage limitations suited to particular species. For example, we might all agree that RES and BG fill separate niches. The RES biomass a BOW might support is largely dependent upon the forage RES can effectively compete for in the presence of BG. For the most part, this forage is those creatures that BG are least interested in (epibenthic/benthic forage). RES and BG are generally capable of filling their habitats up to the forage limitation. They compete for 02 equally and water quality affects each. I agree that when DO and water quality can't support the to total biomass at the forage limitation fish will die.




These are good points and valid. However, even with a doubling of carrying capacity, the question remains about how much of that capacity belongs to the tilapia themselves. It would be great if all win, but I still think it isn't fully clear under what conditions tilapia can circumvent the BG food chain sufficiently to impact BG biomass and condition. With regard to LMB, the benefit seems a forgone conclusion. With regard to BG, I would like to understand more.

On water quality, I totally agree on the benefits mentioned and I agree this effect gets relayed across the food chain as your described. The SRAC has a fact sheet on PAS culture of catfish in combination with Tilapia. The TP provided water quality benefits that allowed for insane production of CC >17,000 lbs/acre. What isn't clear is whether quality benefits outweigh food limitation effects for specific species like BG where TP convert primary production into biomass that the BG cannot eat. This might however be overcome when the TP die. BG could shred and eat large TP as they decay or eat the creatures that are eating dead TP. As I said, I would like to know more about the BG interaction.

That doubled biomass excludes the weight or biomass of the Tilapia... I was not clear. That doubled biomass will be in the "normal" biomass Bass, BG, CC, etc). Tilapia are like adding a feeding program, aeration program and chemical eradication program...with edible tails and scales. Like when adding commercial feed and aeration, you will increase biomass...in turn, take those away (or Tilapia after about 3 years, and you will have a lot of starving fish and possible O2 crash await you. Do NOT consider the Tilapia as being one more species in your pond...think of Tilapia the same way you consider aeration, feed, or chemicals...The Tilapia are only temporary and add to the other species in the pnd, just in multiple ways.

Your SRAC fact sheet will be in high density commercial food fish production ponds that are definitely "fed" pellets and use multiple 50hp agitator paddle wheels...and at 17,000# per acre, probably with a raceway system too, in order to flush and concentrate waste into the center of the pond.

All the Tilapia do is take the tons of wasted nutrient (algea and detritus mostly) and convert it to an edible form for the other fish species....all other fish species will increase in numbers, length and weight when adding Tilapia...You still have to be the apex predator and remove those nutrients, by fishing a lot more

Well, you could take a midnight boat ride in Nebraska to get started writing......

I would never argue differently. When I agreed that I would like to see research I speak specifically of gaining knowledge of how they may affect BG.

I have a 1/8 to 1/10 acre forage pond that I'd like to make into a good spot for my grandkids to catch big fish we can eat. (Also to keep some of the large LMB around the dock from being hooked!) Was thinking of growing CC, but you've got me interested in TP as well. Feeding would be done, and I guess I'd need aeration as well.

Any thoughts on how the CC plus TP combo might work? Can TP be caught on a hook, say with a Stubby Steve, in such a situation?

Hadn't thought of it that way ... but can see the wisdom in doing so.

I would LOVE to create some indisputable research on using Tilapia in sportfish ponds....there really is none...Research is expensive, and since Tilapia are the number 2 farmed fish, all the research pertains to food fish...Unfortunately, to grow Tilapia for food, everything is the exact opposite of the gaols or methods used for sportfish ponds. In our ponds, we want mixed sexes for high reproduction...in aquaponics and food fish production, NO reproduction is wanted and females are sex reversed to males, since males grow faster and no feed gets wasted on egg production or small fry....anecdotal evidence and observations are all you will find. Your proof will be finding more, bigger bluegill in a trap or rod and reel.

The only negative "conclusion" I have ever seen is by TPWD on a southern Texas lake that had a LMB decline.....the biologist in charge could not find any cause, so he simply blamed Tilapia, yet had nothing that supported Tilapia being at fault. (in fact, the report stated Tilapia were in all fish tested)..seems to me tilapia were keeping things fed....

Lastly, I have seen ponds and talked with owners of trophy bass ponds that routinely stock at rates from 200-500 pounds per surface acre yearly....all they ever get are bigger fish, whether it be BG, CNBG, LMB, RES, WE, SMB, CC, etc. There is no doubt a point where everything crashes, but I've yet to hear of it, except in RAS monoculture systems

Perhaps in that case the lake was so far south that the annual TP die-off doesn't happen?

The Tilapia there are Blue Tilapia, probably a hybrid that will die around 52 (pure die at 45). Contrary to what you may think, there is no late fall/winter reproduction and often the temps drop to the ranges that cause Tilapia to become lethargic. There is no known lake or pond in the USA that has become inundated with Tilapia....In order to spawn, Tilapia need temps above 70 AND a longer photoperiod than exists in North America outside the mid springs, summers and mid falls for more southern latitudes. If you get any cool spells, Tilapia will concentrate in warm water pockets, be lethargic, and get hammered by everything that can eat them.

In TX, you can only stock Mozambique, because the lethal temp is 52-55...but in south Florida, the more cold tolerant (45*) Blue Tilapia is the only Tilapia allowed to even be possessed

Buddy, Tilapia in LA will get your pond drained and sterilized...but on the bright side, the state or Fed will probaly feed you for months to years.....Tilapia are Very frowned upon in LA!!! The state even rotenoned over 100 acres of a bayou where ONE tilapia was found a few years ago...prolly killed every fish EXCEPT tilapia too...

I was just suggesting a possible reason for the exception. An annual die off seems to me to be good thing that ensures their benefit. We do have blue tilapia which persist in some reservoirs down here. I am unfamiliar with the case you referenced and TWPD determinations/conclusions.

Now you've got me looking for it. Not sure if this may be what you were referring to?

It may have been Fairfield....I can't find the study either now, so it may have been pulled....Here is some TX propaganda for a read...I hate to even start on how much in this is completely false, but hey, it's deemed an invasive, so they need to scare readers... http://www.tsusinvasives.org/home/database/oreochromis-aureus

They may have backed off blaming tilapia for Lake Fairfield fish kills. What I've been able to find ... they stop short of doing so. This lake and similar lakes which experience frequent fish kills are power plant lakes which have very warm water. In late summer and fall as day length shortens significantly, water temperature remain high which keeps fish life oxygen demands high and bacterial activity oxygen demands high. These kills might likely happen with no tilapia present. Tilapia are in these lakes because they stay warm enough to keep them alive through the winter.

The link you provided suggest that in some cases the power plant companies have stocked the fish themselves.

I prefer not to talk about my heroic actions that night. Thor comes to mind. With my platinum mane glistening in the moonlight, I can think of no one else.

I don't have a number. I was just curious if the number itself might have motivated you stock the TP. I've been releasing all the bass I catch in local public BOWs. Some have decent length. I would say their condition is poor any time of year but don't know their RWs.

Frank, I can not speak of the CC but I can say catching Tp was no problem at all when I had the high numbers of them in the pond. A beaded fly would catch one as soon as it hit the water or within a second or so after it hit the water. When fishing around the feeders. Most of them ran in the one to 1.5 lb range. I did not want to increase the feed amounts or I am sure their average wt would have been much higher. And because of such high numbers of them, I was visited by all kinds of fish eating animals and birds at the time. I can also say they were really good eating, much better than bought at the store.

I get that. I'm not much of a record keeper either.

Ouch! OK I'll quit asking.

JPS, I was agreeing with you. You and I are each moving LMB for a specific reason, and I rarely weigh or measure my LMB when doing so. It's a number's game for me, so the only valid and consistent info I have is from my electroshockings. We get one every other year.

OK.

You just seem to have very good handle on your BOW. When I read discussions in threads ... sometimes I am just filled with curiosity with what is possible. Like is a standing weight of 300 lbs of LMB possible with TP? How does Al achieve 1.5 # bluegill and 8# bass at the same time? I have a great measure of respect with what you've accomplished with your BOW. I wouldn't otherwise ask. It was a lot of questions and I can certainly understand if you felt a bit perturbed with so many all at once.

Thank you for that, but here's the deal. I have an 11 acre BOW that goes from a pond, to a puddle, to a swamp depending on the rain we get, so I always try to be careful with sharing what experiences I have here that might be unique to my particular place. Tilapia are fish I've stocked for algae control, LMB snacks, used for LMB forage in my little hatchery pond, and grown out fingerlings from male/female breeding pairs, so I feel comfortable sharing what I know. The thing I can't give advice on is numbers to be stocked. I've targeted tilapia stocking based on whatever the goal for the year is, so even here, the poundage and size can change annually.

I'll be more than happy to answer any questions I think I can give a valid answer too. I just don't want to throw anything crazy out, because believe me, I've tried it all.

You're absolutely right, thanks for the warning. Fortunately, my BOW is in Texas.

Your situation is tough, but the advantage is that you indeed HAVE seen it all!

Thanks, Tracy. That's encouraging, except for the fish eating animals & birds part! One advantage of my growout pond is that the water is very fertile, viz never exceeded 12 inches, so predators had a hard time seeing & taking the fish.

I will try to dig out some of the studies on TFS vs BG vs Tilapia. They are all over the range of results because the lakes and conditions varied - it all depends.

TFS and BG eat different things at different times and generally only compete for food at the very margin. Bob noted this. Plankton present and when the small yoy BG eat it are different from when the TFS eat the same plankton. TFS are mostly consumed by small to mid sized LMB. Bigger LMB 4+ lbs do much better on larger BG and Tilapia - Rex noted this - as a big LMB chasing TFS is an energetic waste for the LMB when it can eat 5 inch BG or Tilapia.

I was involved in the study Bob mentioned. I have serious doubts that the LMB were not eating tilapia. I think it was a size and time of year aberration. In the very least they removed pressure on the BG ,shad and other possible forage species. There were many species present - not a traditional LMB , BG , tilapia type lake.