It becomes cost-prohibitive to raise largemouth above fingerlings. And, they become cannibalistic at around two inches so survival beyond that is unpredictable. To get past fingerling size, they have to be graded frequently (to reduce cannibalism, with mortality occurring each time the pond is graded) and provided live forage fish or trained to accept fish feed. For biosecurity reasons, they would either have to purchase forage from certified disease-free baitfish hatcheries or devote some of their production ponds to forage fish only. And, feed training is more complicated than it sounds.

The stocking survival rate of harvest-sized fish would certainly be far better than fingerlings, but the numbers that would be stocked would probably be so low that people wouldn't think it beneficial. At least when they say they stocked 500,000 largemouth fingerlings there is a "wow" factor with the numbers introduced. Even if only 1 to 5% of those would ever get large enough for you to catch (I don't know the exact figure off the top of my head, but it's closer to single digits than you would like).

Side note; one reason trout can be grown to harvest size at a reasonable cost is because they readily accept fish feeds. Largemouth have to be trained to do so, and even then they need live forage to get above about 10 inches, according to what I have read.

I have a question. Why did EV Spence get nearly 110,000 fingerlings in 2013? It currently sits at 1.8% of capacity.

I think a lot of folks are missing the point of why TPWD is stocking LMB in the first place. In most all cases, it is not to increase the population of fish in the lake, but rather to influence the genetics to have more Florida Strain characteristics.

I look at it like this. TPWD has been stocking roughly 500,000 fingerlings per year in Lake Fork for several years. The female LMB lays on average 4000 eggs per pound of body weight. At those figures, it only takes 25, 5 lb females in Lake Fork to match the stocking of TPWD.

On the flip side, they are stocking pure strain Florida LMB. Out of the 500,000 that they put in, lets just say 1 half of 1% made it to maturity, we are still talking about 2500 fish a year that have the potential to become a trophy sized fish.

And then they cross breed making hybrids which the SAL program will reject. It's a silly program and there are much better things they could be wasting money on.