Pond Boss Forums Thread Like Summary - Too Many Brooders??

Before I go 8 miles down a dead-end road, I need help figuring out if I am even headed in the right direction.

I am trying to rebalance a >35-year-old retention pond 3 acres in north FL. I have reduced the number of skinny LMB over the past 3 summers. Fishing effort has gone from .7 fish /hr. to .16. although the RW have changed little and are still in the 75% range. Most LMBs are still in the 11-13-inch range. I very rarely see or catch anything in the <11inches. I am not a highly experience fisherman. I have expected more of a change in the RWs.

I believe I have more BGs than in years past. Last year I used my Z-trap baited only once & caught Zero BGs. This year I average 10 a night in the 3–7-inch range. With a baited minnow trap, I very rarely catch BGs in the .7-1.5-inch range. The range of sizes caught in the Z-trap are roughly equal for each size & RWs are near 100%. There is not a size that is predominate. I do hand throw 2lbs of food a day. Osprey, Anhinga, & great blue Heron have spent many more hours fishing at the pond than in recent years past. I am surprised with a few BG & Redear crosses, also BG & Warmouth crosses.

When angling for BG, they are easy to catch, are in the 8–11-inch size with the RWs at 100% range. While angling the <6-inch BGs are very rarely caught. All BGs from 3-10-inches have been fin trimmed, with only 2 in the 4-7-inch range being re-caught out of 80 fish.

What to do now? Electro-fishing is not an option.
Continue on as before? Removing skinny poor performing LMB. BGs are fine & numbers recovering? LMB will follow?

Reduce the number of brooder BGs 5-9 inches? Remove females, return males? Trying to reduce competition & increase the numbers of fry & fingerlings?

Survey recatches? Increase number of marked fish? PSD?

It depends?

Thank for your time & help!

Aside: Tug of War 1 to 1. I caught an 8" 7 ounce CNBG because of PP poor planning my scale, ruler & hemostats were not close. Leaving the BG in the water, I tried to develop a plan. Then the tug of war was on, line quickly being stripped from my ultra-light reel. After a minute the BG was released & I weighed, measured & fin trimmed the BG. 15 minutes later it happened again. This time I lost the BG, leader, hook, & sinker to a demon of the deep. I did not think I had a LMB big enough to take a BG that size, >16". Hope she does not have indigestion.

I am not sure what is meant by the comment of ...."what Dave, esshup, Bill, Bob, or ewest thinks is consumable."

Obviously if the forage item is not eaten for whatever reason it has no benefit for the physical growth of that fish at that instant . However if that uneaten forage item is able to reproduce it does have a benefit to that fish and other fish who can benefit from the reproduction that is consumed a later point in time.

The other variable to this lack of growth of the LMB is one has to remember this FL pond has the possibility of other species of forage available to the LMB as noted by in posts by J.E.Craig as "The pond’s original populations include LMB, CNBG, CGC, RES, MF, Eels, Br. Catfish, Bowfin, snails, mussels, clams, crayfish, shad, gold shiners". The other concern to me is what other predators that are listed as "Regular visitors include River Otter, GBH, Anhinga, Osprey,.." and what influence that they could have on the fishery balance. The pond's fishery is likely complicated and not just one based simply on BG and LMB. I think one also has to consider the type and amount of habitat available that influences the balance of the fishery.

I am not saying that jpsdad in wrong in his thinking. It is just the fishery for J.E.Craig is not just a simple BG-LMB fishery that could be complicated by other factors working within the Florida 3 ac pond. Complexity could make the fishery balance not a simple one.

To be sure, it's not meant to offend anyone. There seems to be uniform agreement that 1/4 to 1/3 length BG are most appropriate, most advantageous and/or most needed to maximize the growth of LMB. My intent is to say I dissent from this widely held opinion. One that is frequently promoted by those with considerably more influence here than I. Most often, I do not reply, dissent, or challenge when this idea is republished here. What makes this case different, is that I am trying to help the OP and I do not want my idea of most appropriate, most advantageous, and/or most needed to be confused with the widely held opinion.

Part of what was snipped was further explanation. Very often, people express the opinion that the forage situation in their pond is very good but then follow that with comments of low RW and slow growth. We can have the wrong opinion about the availability of consumable forage. When RW is low and growth is slow ... most often ... there isn't enough consumable forage. When this occurs and we think there is lots of forage to consume, we should review ourselves. We should seek to understand why our opinion is not consistent with the evidence.

To provide an example of a case where the opinion of what is consumable is clearly incorrect ... read this paper which is the first documented test of the use of formulated feed in a sport fishery (that I am aware). The paper documented effects of feeding. There was a control, a test pond that was drained along with the control for comparisons (after 19 months), and finally a sport fishery that was exploited over the course of 4 years.

Although, the paper documents the substantial increase of potential in support of the forage species (BG), there were some disappointments. For example, the test pond that was drained after 19 months ... it only had 29.4 % higher standing weight of LMB than the control which wasn't even fertilized in the prior 12 months. It is a great example that greatly expanding the forage potential will not necessarily proportionately expand the standing weight of LMB. To be sure, the LMB had the potential to grow much more than they did. The reason they didn't, was because they did not consume enough BG to grow at their potential. I will be first to note that it was NOT the fault of feed that the LMB did not reach greater proportions of their potential. The balance of predator and prey (particular the size of the predators at the time of stocking -- should have been larger) could have been better. But this does deal with the appropriateness of relative sized prey. Much of YOY produced quickly outgrew the capacity of the LMB to consume them.

So the success of feeding in terms of supporting greater weights of the forage species is not in question. However, the idea that supporting greater standing weights of forage fish must lead to proportionately greater consumption of the forage species by LMB .... well that is. This experiment is evidence of that.

Now on to the sportfishery. The sportfishery finally failed and reached a point of considerable imbalance. The pond appeared to be in balance for the first couple of years -- meeting Swingle's definition of balance. But ultimately, the project failed miserably in comparison to Alabama state owned lakes with regard to the LMB. The exploitation of LMB was significantly less in the fisheries test pond only being a minor fraction (69%) of the state owned lakes. This despite the remarkable standing weight of BG carried in the test pond and good gross production of BG. Presumably, LMB carry and exploitation should be proportional to the water's ability to support the forage species. This is an example where that presumption is false. But again, it was NOT the feed's fault, it was that the production of BG that the LMB could consume was lacking (But again, this does deal with the appropriateness of relative sized prey and their abundance).

At draining, they assembled the balance statistics for the fisheries pond. Forage comprised almost 97% of the biomass ... where LMB comprised only 3%. What was remarkable to me was the reported Y/C. This is the ratio of the biomass of consumable prey to the biomass of LMB. In 1964, it was widely agreed that BG between the sizes of 1/4 and 1/3 proportionate length were consumable, important and advantageous prey for LMB. So my impression is that they counted all prey less than 1/3 length of the average LMB (~13" LMB) in this accounting of Y/C.

But here is the rub. Y/C is not just a metric. It incorporates opinion. First, one has to go out on the limb to define "what consumable is and means". Once he has done that ... all metrics he gathers pertaining to Y/C is tainted by his definition which ... without corroborating research ... is simply an opinion. IOWs, when based on an opinion of what defines consumable, reports of Y/C are not objective but rather subjective, subject to a definition that may not have basis in fact. In this paper, they report a Y/C of 8.0. That's a massively high number that suggests that the LMB were swimming in consumable forage. In the context of LMB growth in the test pond it just doesn't make any sense. If it were really that high, the growth of LMB and the average weights of LMB would have been much higher. There is an incorrect definition of "what consumable is and means" at the heart of the disagreement. They were counting forage fish as consumable when they really were not all that consumable free chase in the fishery pond.

Alot of people will read a paper like this and just take what they want from it. They may take, for example, that a fed pond produces larger BG relative to a pond that wasn't fed. I noticed that but I also notice things like E-LMBs of 3% and Y/Cs of 8. I notice how inconsistent those metrics are. I noticed that the test was a failure for LMB. I can't help but notice things like that ... in addition to the greater standing weights of BG and better early growth. I don't just take what I want from it ... I take it all in ... and I try to put all of it into an understandable representation of basic but indisputable principles. For example, principles based on energy balance and how these limit standing weights and the production of consumable/consumed forage. That's what I have been sharing in this thread and the must-read thread. I mean to improve our understanding of these things ... that is my only intention.

I hope ... that all read this post thoroughly ... so that they may understand why I can't agree with the idea that 1/4 to 1/3 sized BG are most appropriate, most advantageous or most needed. I believe otherwise because of a substantial volume of studies (many of which I have already posted here) that do not support that idea. The reason I share my dissent? Because I think it can help everyone make better decisions that result in better outcomes. It's not a shortcoming to be wrong about something one has been taught. It's a strength to question ideas and to be persuaded by good arguments and supporting evidence. Sometimes this requires abandoning an idea that one once believed. This isn't a shortcoming in the least. It takes strength to recognize when one has believed an incorrect idea and to change his mind. All anyone can expect of others is to have good intentions and to do their best in terms serving their interests. Part of that is learning to improve what that best effort can be. Knowledge never sits still. Scientific research is always testing the status quo skeptically. This is how we improve.

Thank you for the vulnerability of bass to angling information. ewest has discussed I think this specific paper in PB magazine. For those interested in reading the summary of that specific article by D.Phillip here is the abstract of the article.
Selection for Vulnerability to Angling in Largemouth Bass by David P. Philipp et.al
Abstract
Although a great deal of effort has been expended to try to understand the consequences of fishing-induced selection by commercial fisheries, relatively little effort has been put into trying to understand the selective effects of recreational angling. We conducted a long-term selection experiment to assess the heritability of vulnerability to angling in largemouth bass Micropterus salmoides. Three successive generations of artificially selected largemouth bass were produced from a single experimental study population. Within each generation, individual adult largemouth bass were identified as having either high or low vulnerability to angling through a series of controlled catch-and-release angling trials. Individuals of each vulnerability group (high and low) were then selected from that population for breeding to produce the next generation. The response to selection for vulnerability to angling increased with each generation; that is, the magnitude of the difference between the high- and low-vulnerability groups of fish increased with each successive generation. Realized heritability was calculated as 0.146 (r2 = 0.995), indicating that the vulnerability of largemouth bass to angling is indeed a heritable trait. Our results indicate that recreational angling has the potential to alter the gene pool of wild fish populations, which may indirectly affect population characteristics such as survival, growth rate, and reproductive output as well as directly affecting angling success rates.

The lack of small BG to me is an indicator of too many LMB and not enough forage. If it was my pond or a pond that I managed, I'd remove EVERY bass that I caught, not just the low RW ones. That would minimize the hook shy ones. Keep removing LMB until you get a balanced size distribution of BG in the pond. Larger LMB won't target smaller BG, but they WILL eat smaller LMB.

After the size of the BG get more varied, only then would I think about removing any BG that are big enough to reproduce. Remember not all of the bass in the pond will strike at a lure. That is why e-shocking is used to check fish populations and not angling.

Your LMB not growing to me means that there still isn't enough forage in the pond for them to grow.

In my personal pond, I tell anybody that I allow to fish it that EVERY LMB that is caught gets removed. 5 pounds or 3 inches, ALL come out. After 5-6 years of that, there are still LMB reproducing in the pond and this pond is only an acre in size. In the summer if I see smaller LMB cruising the banks I will go to a small bait and 2# test line to specifically target them, sight fishing for them whenever I see them.

If the catch rates of the LMB in the pond start dropping, then go to live bait. #2 wire hook tied directly to the line, 8# test fluorocarbon line, a weight 12" pinched above the bait to keep it at a certain depth and a bobber that is enough to keep the bait from taking it under the water. I'd try fishing with 4" golden shiners.