Thanks esshup, that is the closest answer to the question I was attempting to ask.
However, I still didn't ask my question clearly enough.
I have read several times on the forum where people have complained that they stocked tilapia, but they didn't even make a noticeable difference in their FA. However, they may have stocked too late for the next generation(s) to make any significant dent in the FA?
If the stockers eat 20% of the FA consumed in a given year, and the subsequent generations eat the other 80% consumed, then it is very important to facilitate the spawning of the stocked tilapia!
I would therefore conclude that it would be a management goal to stock the tilapia at the earliest "safe" date so they can more quickly initiate their subsequent breeding cycles.
I guess that leads me to three new questions:
1.) Any estimate of the % of FA consumed by the initial stockers versus the % consumed by the subsequent generations for "single-year" tilapia? (I know that is a nearly impossible question to answer. Did Rainman ever discuss that since I believe he delivered tilapia year after year to some more northerly ponds?)
2.) If the subsequent generations matter a lot, then is there anything a pond manager can do to aid spawning success of the tilapia?
3.) Has anyone observed a tilapia kill because they introduced them too early in the year and a cold front or cold rain wiped out their stockers?
(Even if the original stockers are responsible for eating 95% of the FA, then determining the earliest day to put them in would still be very important. Stockers getting more "eating days" and being much larger at the time of the winterkill would definitely provide much better FA control.)
P.S. I have read that tilapia can spawn year round, and that female tilapia can spawn every 17 days under ideal conditions! I assume that means a fish farm in equatorial Africa. Any ideas on observing tilapia spawning in the temperate zones of the U.S.?
P.P.S. Would it work to have a very shallow grow out pond to jump start your tilapia production? I am imagining a shallow pond that reaches a "safe" water temperature much earlier than the main pond. Create some good spawning beds and add some tilapia brood stock. Add a bunch of loose hay(?) to get a bunch of zooplankton going for the fry. After the fry hatch, move the parents to the main pond if the water is warm enough to avoid cannibalism. Move the 10,000 tilapia to the main pond as soon as they are beyond the mouth gape of the BG, or any other small, numerous fish in the main pond.
Just throwing out ideas for discussion since controlling FA and tilapia seem to draw a lot of questions from newbies and experienced pond managers on the forum.
