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.
