Pond Boss Forums INTRO Questions & Observations What fish combinations for a tiny BOW?

I've been considering building a BOW on a 2 acre property. Though the property receives water from outside, the watershed is very limited and I think I will be limited to a BOW of about .18 acres. What I have imagined in this space has changed alot the past few years.

It's easy to imagine something bigger and better than the space allows. In a typical LMB/Bluegill combination, appropriate harvests range 10 - 25 lbs/acre-year for LMB and 30 - 60 lbs/acre-year for Bluegill. So for a .18 Bow we're talking between 7 to 15 lbs per year. To be sure, I just want to have fun with my son and daughter and (hopefully the eventual grandkids) and the size of the fish, provided they are a harvesteable size to filet, is not of great importance to me. Were I to state a goal it would be this, I would like to harvest a minimum of 300 lbs/acre year of fish > .25lbs in weight AND I want the standing weight to NEVER exceed 500 lbs/acre. I already know I can do this with catfish, but I want different fish and would only consider stocking them at 50/acre (10 annually preferably all harvested annually).

I've whittled dozens of considerations down to 3 favored scenarios but before I describe them it would be good to discuss how the goal above is limiting my choices. First to have a harvest that great with a maximum standing weight so low probably requires (I think) that the fish are harvested 0-year and/or 1-year of age. Where a predator fish is expected to reproduce, it must attain a weight that would allow it to reproduce at 1 year of age (or a very limited few at 2 years). LMB or SMB with sufficient growth can do this but I have reservations as to whether sufficient cannabilism would occur to allow them to achieve 9" by year 1. Ideally, year 1 predators would reproduce and all or most of year 1 predators would be harvested over the following 7 months.

For the predator food chain, I want a vibrant community of invertebrates and small fish of sizes to be ideal for predators up to 14". From the ground up they would include shredders hyallela Azteca and PK shrimp. They would also include fishes Gambusia and Red Shiner. These are chosen on the basis of high reproduction rates, mobile maternal care of eggs, in the case of the shiner the freedom to spawn without parental care. I would hope these forage would overwinter sufficient populations to repopulate each season.

It is not likely, even under ideal forage conditions that the predators would attain sufficient mass to meet the harvest objective. So to fill this gap I think Mozambique tilapia are a good choice. I like them for number of reasons. Although I would expect them to consume some of the forage, I do think this will be limited. I am hoping they will help to reduce phytoplankton and FA abundance and improve water quality where fertility is enhanced. They would more efficiently produce fish flesh than the predator food chain. Swingle found Mozambique tilapia to be the most catchable of tilapia by hook and line in his trials. They reproduce at a young age and I anticipate that the majority of resident predators will not be able to capture 4" tilapia. I think I can produce the quantity I need from an overwintered pair of fish from a single spawning. Would just need to protect the fry/fingerlings until they reach 3.5 to 4". I anticipate the timing of tilapia introduction would be in the early July time frame and given the introduced fish will have just reached reproductive size and age I would expect that some would be spawning by August. I would hope the tilapia offspring would never reach a size too large for the predators to eat.

So what about lepomis? Well I like them, no I dearly love them, but they would destroy the initial goal I think. Within a couple years, if harvested at the rates I want to harvest, I think their numbers would be excessive and the sizes rather small. The bow would always be at a large standing weight and small prey species would never achieve the abundance they would without them nor would the food chain produce fish flesh as efficiently. In the end, I think the sustainable harvest of predators w/o BG would be greater than a sustainable harvest of BG would be (unless one is harvesting <5in BG ... a situation I do not want). Still I see BG and LES making their way in as a male only bonus fish at the rate of say 2 to 4 annually (10 to 20 per acre-year).

OK, so now my top 3 considerations for predator are HSB, SMB, & LMB ... in that order. Because the numbers of HSB can be tightly controlled I did work up a "plan". I am pretty sure I would be happy with the HSB/Tilapia combination and I think it would exceed my stated goals. Concerns I have about HSB are whether they would survive well to 13" in a tiny BOW here in Texas. The annual cost of 1 1/2 inch fingerlings wouldn't be cost prohibitive but they would require the attention of a grow out to a size they could evade predation.

I like SMB because they could reproduce and ideally replenish on an anual basis. I like them also because they more efficiently utilize invertebrate prey than LMB. It may be possible that they may be able to grow faster than LMB in their first year assuming the same number of recruits. I like SMB because snrub has successfully fed them without training which might help to boost their size. If I have concerns, it would be that cannibalism would be insufficient for them to reach a reproductive weight by year 1. I also have concerns that they might not as effectively inhibit tilapia recruitment and convert less of this resource to fish flesh. Insufficient predation of tilapia recruits would also reduce the weight of harvestable tilapia (the stockers).

I like LMB because I think reproduction would be less of an obstacle for them than SMB. I feel confident that LMB will be more oriented to consume tilapia recruits converting more of this resource to fish flesh and increasing the stocker tilapia growth. So my concerns are, despite these favorable traits, that LMB might still over recruit preventing Year 1 LMB from spawning and a sustainable harvest of Year 1 fish.

To be sure. I lack the experience to understand the best combination. I think if I could be certain that the LMB or SMB route would work with my harvest objectives I would favor them to avoid the necessary yearly introduction of advanced fingerlings that HSB would require. I am interested in whatever thoughts Pond Boss forum members may have particularly with regard to the LMB and SMB combinations and whether year-1 reproduction and year 1 harvest is sustainable or whether a different more complex age structure will likely be required. Thanks in advance for any and all ideas and comments.