Pond Boss
For those who want to follow the whole story a link to part II is here

I’m beginning to wonder if I might need to do a BG cull…

The 150 BG I stocked last April have taken over the pond and I can easily catch 8-9” BG that weight up to 9oz. The young BG are also along all the shore lines. They are clearly very happy in the pond.

I have a Texas Hunter feeder and was feeding them 1s once a day last year and the fish ate but it was not very enthusiastic. That has changed. They are now piranhas with the big ones competing with all the smaller size classes. I stayed at the 1s once per day, but today added a second feeding of 1s.

The LMB remain small (avg=9in) and generally below the 100% RW. Given the huge number of BG in the pond it’s a bit puzzling to me. The last two I caught were both 7.5 inches and skinny. Fishing is not the most scientific sampling, but I should have started to see some that are bigger than the 9 inch average that I saw all last year- especially since I’ve removed ~150 LMB in the past year (including the aforementioned pair of 7.5 inch fish).

Should I start taking any action on the BG or just let it play out for another year or so?
I say if it's skinny, cull it.
There are times of the year when WR of fish may be slightly below 100% and still healthy such as post spawn. It takes a bit of time to rebuild the weight lost during that time but at 90% WR, it takes a fairly trained eye to visually see that. Below 80% should be fairly noticeable and those need to go..
What is your estimate of percentage of shallow shoreline cover (dense), say in 1-3' of water? Over 30%???

How many BG do you have >3" but less than 5"?
I'm sure no expert, 1997, but sounds like you may have old LMB that simply don't have much growth potential left, regardless of the amount of forage. Worth checking. If so, you can buy some young 6 to 8 inch LMB and see if they do better.
In my experience, stunted LMB grow remarkably well when there is sufficient food (means little competition). One must meter his expectations within the constraints of carrying capacity and the limits nature imposes. We know the pond contained in excess of 225 LMB per acre because that's the harvest so far in the first year of numbers management. If the pond originally had 450 LMB per acre, then we could only expect the harvest thus far to double the weight the remaining LMB. That is ... all other things being equal.

But they are not equal, BG have been introduced and they compete with LMB for a portion of what they were eating. Large insects. So as for the large insects the LMB were consuming they now have to share that resource with BG and since the BG are recruiting, they also compete by consuming the prey of large insects and some of the large insects when they are smaller in size. The results thus far are consistent with this scenario.

The thing we need to keep in mind is that the presence of BG will not increase the carrying capacity for LMB. The effect relative to "LMB only" may even be to negatively impact LMB carrying capacity. What the BG do is make possible a smaller number of much larger LMB. Its early in the game and the original BG could make it > 2 lbs. So what to do from here in many ways depends on what the OP's goals are.

1997, if you are enjoying the large BG the goal of larger LMB will conflict. But anthropic's idea of a handful of feed trained LMB in the 8" to 10" sizes would allow you to grow some dandy sized LMB that are less dependent on the food chain. They should also take chunked BG that you cull. If a small number of LMB can bypass the food chain for nutrition and be fed with little competition from other LMB they can grow large. It would be like having cake and getting to eat it.
I'm going to try and take the responses and questions in order:

- The pond has steep banks quickly dropping to 6' and is 11' at the deepest. I'd estimate 5% of the pond is 1-3' and there is little thick cover, except for the 1-2 scrub cedar trees I stuck along shore to provide cover.

- BG size appears to jump from large (I'm guessing the survivors of the orignal 150 stocking of 4-5" BG) to those that are ~5" and smaller. There appears to be an even distribution in sizes below the 5" based on observation, fishing, and minnow trap catches. Hopefully that answers the "how many" question from a proportional count perspective.

- Yes, I was looking at stocking new LMB to add to the gene pool. The most recent Pond Boss Magazine had an article on just that topic. I'm just at the considering stage.

- A lot to unpack on jpsdad's post. Completely onboard that the small pond can only carry a handful of bigger bass. I'm also want to work with the pond and not against it. I'll keep trying a few things to see if I can have a healthy BG population and get a few bass up to bigger sizes. If I end up with a pond with 1-2lbs BG and few bass that ain't a bad thing. I do find the idea of getting a few pellet trained LMB and potentially feeding then chunked BG intriguing.

I'm also fishing other waters and if I have the chance to relocate a 2-3+lbs LMB to the pond that would be fun. That LMB would truly become the pond boss. smile
Originally Posted by 1997pond
- BG size appears to jump from large (I'm guessing the survivors of the orignal 150 stocking of 4-5" BG) to those that are ~5" and smaller. There appears to be an even distribution in sizes below the 5" based on observation, fishing, and minnow trap catches. Hopefully that answers the "how many" question from a proportional count perspective.

OK so the reason I asked is because once the BG recruits get to 2.5" they are resistant to predation for your current population of LMB. In other words, they aren't prey. To complicate matters, they compete with the original BG and will undermine their growth. So yes, those in this size range can be culled and repurposed as chunk/strip food for the LMB. This past weekend my son & I spotted a big catfish cruising and so we chunked a 4" bg in 3/8 inch crosscuts. But on the first two casts LMB took the falling chunks ... one ~8" and the other ~ 10". After the LMB we were able to get a chunk to bottom where he caught the big CC. So yes, LMB will take chunks of BG (even hotdogs) without any training. But I think if done frequently and regularly that you would probably get some reliable takers. If already feed trained, the leap isn't far at all.
Makes perfect sense. I think that would also be the benefit of introducing a 2-3+ pounder into the pond. It would cut through those middle ranks and ... in theory.

There are still hundreds if not thousands of BG in the <2.5" range and I know there are a handful of 14-15" LMB that have been caught and released. Again, fishing is not a great way to sample so maybe I'm just missing something.

On a related note-
With a large healthy BG population that is spawning throughout the Spring/Summer, shouldn't that be providing a near continuous stream of fresh small fish as a food source? Are the BG just eating their own?
Originally Posted by 1997pond
On a related note-
With a large healthy BG population that is spawning throughout the Spring/Summer, shouldn't that be providing a near continuous stream of fresh small fish as a food source? Are the BG just eating their own?

There will be large spawn with other peaks in spawning. There is probably a good number being produced. Some of the spawn is eaten by BG though I can't venture a guess what proportion. The rest that don't outgrow the gape feed LMB.

If the average prey size is 1% by weight (a very reasonable estimate) and if it takes 5 lbs of prey for maintenance then for a 1 lb LMB it takes 500 BG every year just to tread water. So even if the average prey were 2% of the weight of the predator it would take 250 BG/year just to maintain that 1 lb fish. If LMB eat prey proportionate to their size, then EVERY LMB requires a minimum of 250 prey fish annually if the average prey is 2% of their weight. But I figure it at least takes no less 300 BG every year for maintenance and so you are getting the picture of how many it takes. So lets say you took 1/2 of the LMB out and there remains 150 left. At 300 BG per LMB you need to produce 45,000 BG just to meet maintenance or 67,000 per acre. So that will tax your pond's ability to produce them. Reducing the number of LMB is obviously the easiest way to ensure there are more BG for every hungry mouth. These numbers make sense and this is a reasonable ball park number of BG your LMB are consuming annually in a slow growth scenario (assuming 1/2 the LMB harvested thus far). Whatever the number is ... its a lot ... and so there must be many thousands of BG dying in LMB gullets.

All the same, think 1% of those 67,000 surving the LMB gape and recruiting to become adults. These 670 fish outnumber your original stocking and have the potential to compete with them limiting their ultimate attainable size. So harvesting some fair portion of those ~670 3" to 5" fish for repurposing will help LMB by feeding the chunks and also by providing more carrying capacity that YOY can fill.

Ewest pointed me to research that reports findings that being fed reduces the energy costs by a factor of 3 to 4. If true and if you were successful at training a few LMB to take chunks, it would take less than 5 lbs per lb for these LMB. It would be on the order of 1.25 to 1.33 lbs of chunks to support one 1 lb LMB. The conversion would likewise improve where 2.5 to 3.33 lbs of chunks could grow 1 lb of LMB. So something to think about. I would suggest a trap like Augie's and to learn to brine the culls so that you can portion them and feed without a lot of daily effort. Youtube has a lot of videos out there on how to brine bait. You could probably feed LMB 3% of body weight per day (for those fish taking the chunks). Were I doing it (and I am not currently) I would clank a pipe to announce feed. That way they know when you are there to feed. This may condition them to come only when you have food to throw.
With regard to stunted fish growing. My prior noted experience is moving stunted fish to an environment where there were no other LMB but where there were abundant GSF prey. It is worth noting that the LMB quadrupled in weight from fall to spring in Northern OK. So they gained in the cool months 3 times as much as they had gained during their previous stunted life. But it is also worth noting that this situation is completely the opposite of the OP's scenario. I stocked very limited number of LMB into a "GSF only" pond while 1997 stocked a modest number of BG into an "LMB only" pond. Be opposites, all other things equal (species interacting with no human harvest), it is not unreasonable to expect opposite results. In other words, instead of LMB benefiting from the prey species ... perhaps they would decline. 1997s harvest was crucial (I think) in preventing the decline of his LMB. I think I can say that because of the evidence. He substantially reduced intra-species competition but the gains thus far have been muted for his predominate sized LMB concentrated in 8" to 9" sizes.

What I have learned from 1997 is that a predator only pond may be more difficult to balance with prey than an existing predator/prey combination that is out of balance. I have learned the introduction of a prey fish will likely inhibit the condition of predators and that moving to predator/prey combination will require a much more intensive harvest of predators than the standard rule of thumb.
Interesting stuff and I again really apreciate the thoughtful and detailed answers. So much that we don't know but experimenting and learning is a huge part of the fun for myself.

I am going to continue my aggressive culling through this year, but will leave any that are larger than 14" and I might spare a few if they are above the 100% RW. I'm also going to add a 2-3+ lbs LMB if and when I have the opportunity. It seems like a good way to control the midsized BG population... maybe even some of the stunted LMB.

I'll play around with chunking the BG and see if I can get any traction. Not sure that I have that level of commitment for catching, cutting and feeding. smile
One of the 3 most important concepts in pond mgt is Total mortalities (natural mortalities plus harvest), as a part of population mgt. Many fish starve or are eaten as newborn yoy. Survivors are eaten as young fish year 1 or later. Some die from other causes like starvation, disease or weather/water quality/stress. Those are all natural mortalities with large variance year to year. Your job is to watch those factors - natural mortalities (or measure for them by survey) and harvest fish - total mortalities to meet your goals and situation. Not an easy job !
A 9" BG @ 9 oz. that you have caught is 112% RW. The bass that you are catching @ 7.5"-9" can only eat BG that are 2.5"-3" in length max. The LMB in the pond might not have enough cover for them to ambush the BG from, so they might be like marathon runners, constantly swimming and burning up calories to catch enough BG to survive, let alone get fat.

The biggest BG are most likely the ones that you stocked, just like you are thinking.

I'd look at transferring LMB that are between 1# and 2#, I am not sure that larger fish than that would do well in the pond since they are used to catching fish to eat in the BOW that you sourced them from. Bob Lusk stocked bigger LMB in a clients pond and found that they actually lost weight ( maybe because they couldn't figure out the best places to ambush forage fish?). Those 1# to 2# LMB would be eating BG that are (roughly) between 3" and 5.3" in length. Don't a lot of LMB that size, just a few, and I would fin clip those particular fish to allow you to see if LMB that size are caught whether those fish were stocked by you or if they grew to that size in the pond.

I didn't see if that pond is aerated or not. If not, during the summer the fish probably won't be able to utilize the water that is deeper than 8' due to low O2 levels.

Another thing to think about is that you need cover in the pond not only for the bluegill but for the LMB. The cover for the LMB has to have openings in it so the LMB that you are wanting to thrive in the pond can swim in/under, turn around and face out to ambush prey fish that swim past. Ideally you'd want to have roughly 20%-25% of the surface area of the pond in cover for the fish in the water depths that they will be able to survive. Depending on the water temp in the pond during different times of the year that may be shallow water or the deepest water in the pond.

It looks like you are just measuring the length of the majority of the fish that you are catching. Make a chart for LMB and another one for BG, get a good scale and record both weights and lengths. That will tell you how the fish are growing, and if a certain length of LMB is under performing (as noted by weight) that will tell you about what available food sources that size class of LMB has to eat. You'd want to cull that size LMB and the next size smaller to allow the available forage fish to grow larger to feed the size class of LMB that is underweight.

If the goal in the pond is to grow big BG, then cull any LMB over 14". If the goal is to grow larger LMB (that will be hard to manage in that size pond) I would recommend culling the smaller LMB and fin clip 50 of the bigger LMB and only leave those fin clipped bigger ones in there. That will also give you an idea if the bigger LMB are getting hook shy (record the number of times you catch a fin clipped LMB and note any identifying marks on the individual fish).

You could buy a fish tagging kit with numbered floy tags, that way you could track the individual fish length/weight if re-caught.
Here is the data so far for 2022. 32 LMB caught and 29 culled (7.0lbs). Forgive the formatting but I think it is readable. My summary stats for 2021 is further down. (I'll take advive for how to better post...)

04/10/22 Y 9.75 6.6 0.92
04/24/22 Y 7.00 1.05 0.44
04/24/22 Y 7.00 1.05 0.44
04/24/22 Y 5.00 0.75 0.94
04/24/22 Y 5.00 0.75 0.94
04/24/22 Y 5.00 0.75 0.94
04/24/22 Y 5.00 0.75 0.94
04/24/22 Y 9.25 5 0.83
04/30/22 Y 6.00 1.4 0.96
04/30/22 Y 10.50 9.8 1.08
04/30/22 Y 9.75 6.1 0.85
04/30/22 Y 10.50 8.7 0.95
04/30/22 Y 9.50 5.4 0.82
05/07/22 Y 8.25 4.4 1.06
05/07/22 Y 9.50 5.5 0.84
05/07/22 Y 9.00 5.3 0.96
05/07/22 Y 6.50 1.9 NA
05/21/22 Y 9.50 6.5 0.99
05/21/22 Y 7.50 2.9 0.96
05/30/22 Y 6.75 1.9 0.89
05/30/22 Y 9.50 5 0.76
05/30/22 Y 9.50 5.1 0.78
06/04/22 N 9.00 4.7 0.85
06/20/22 Y 7.50 3.0 NA
06/20/22 Y 7.50 3.0 NA
06/25/22 Y 10.00 7.4 0.95
06/25/22 Y 8.25 3.5 0.85
06/25/22 Y 7.50 2.6 0.86
06/25/22 Y 10.00 6.6 0.85
06/25/22 N 10.50 10.7 1.17
06/25/22 Y 5.00 0 NA
06/26/22 N 10.50 10 1.10

Stats for 2021. 148 LMB caught and 128 culled (40.5lbs). The population was very homogenous.

Length (inches)
Average: 8.7
Median: 9.0
StdDev: 1.5

Smallest was 6" and the largest was 14" There have been only two bass caught bigger 12" or larger. 90% of all bass have been below 100% RW
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