I don't know the answer but can share my experience of my daughters pond.
I refurbished it by digging out all I could of the old pond and expanding it to about triple original size. There was a small BOW that I could not drain or get cleaned out. It was stagnant, nasty and as far as I could tell all I could see in the one thousand or so gallons left were some Gambusia. I assumed there were probably some GSF but never really saw any around the bank. I assumed no LMB could survive in what was left of the water (assumptions are always a bad thing).
I stocked the new portion with FHM, BG and a few RES of various sizes from my pond. The old portion of the pond and the new portion I stocked did not join together till about a year later because of drought and little runoff to fully fill the pond. So the stocked fish had a chance to spawn and establish.
That was a couple years ago. Fast forward to about April of this year. I strolled out around the pond to see what I could see. Saw some smaller BG and a nice 8" or so BG. No minnows which surprised me. Was afraid I had maybe waited too long to stock predators and the pond would be over run with BG. But did not seem to be. Then along came two LMB about 10-12" long pretty as you please.
So in a puddle only maybe a couple feet deep with very bad quality water there must have been LMB left.
The pond stocking turned out ok. Unfortunately my daughters husband suddenly came up with cancer a couple months later and died and he would have been the angler. So the pond is mostly for aesthetics now anyway although my daughter does enjoy walking around it and feeding the fish sporadically. So the fish that are in there are "good enough" to serve her purposes.
Point being, just because you never see nor can catch any LMB, does not mean they are not there.
Last edited by snrub; 07/13/16 08:09 PM.
