Very likely that FH could consume more PS than the PS could reproduce. This has been documented in BG only ponds after the intro of FH. In a few years BG were almost impossible to catch as they had mostly been exterminated.
By the time a flathead reaches 5lbs, it is a creature that wants to grow 3 to 4 lbs per year. At the lower growth we are talking a 30 pounds of forage for growth and 25 pounds for maintenance and so roughly 55 pounds for the 5# spring flathead. With a 20 lb flathead we are talking 130 lbs of forage. This tells me that more than 25 lbs of flathead/acre will stress the production limits of many BOWs. Sand Lake was considered borderline eutrophic and it isn't clear what weight of forage it was capable of producing. Even so, it seems plausible to me that the flatheads' needs ultimately reached the prey production limit at Sand Lake.
LMB do that to, all the time when you think about. The answer to that problem is a fish harvest and from a management perspective, the same applies where FH are used to control BG overpopulations. A regular stocking FH of a starter size (say 5 lbs) and harvest of minimum length FH would prevent the FH from attaining to large a mass.
Improving condition of BG status resulted in many more BG being hatched and those were not the prime FH food source (to small at the beginning).
There are theories that predators prefer the biggest prey they can stuff in their mouth but these theories have never been supported by evidence. We know they are limited by gape but this limit has never been shown to be what they prefer nor what they tend to eat. With increasing gape there is a tendency to eat larger prey and that ... when you think about it ... is just because they can. There is a preponderance of evidence that suggests that piscivorous predators
tend to eat prey at about 1% their body weight. A flathead is going to take any opportunity it gets, however, if it is close enough to suck in a 3" fish it is going to do it without worrying about whether it expended too much energy opening its mouth.
IMO the larger BG are most at risk when the production of 0 through 2 year BG are no longer capable of sustaining and growing FH Biomass
