I have finally taken ownership of my new pond. Fished it the morning before the closing. 12 fish in 45 minutes of fishing a mini crawfish crankbait: 6 LMB(3 small, 3 12") and 6 BG/HBG(1 9" BG, others small). I finally got to talk to the previous owner and he said it was stocked with LMB, BG, HBG, crappie(don't know which), and CC. How many fish should I be harvesting to keep the populations in check. It is 3 or 4 acres, have not measured it yet or the depth. The fish look fat and healthy, and I want to keep it that way.

Any idea when it was stocked, numbers stocked of each species and schedules?

All of the fish were stocked at the same time about 12 months ago. They were the species listed above. He did not remember how many of each, just several sacks of each from the "fish truck that comes down from Arkansas regularly". The pond probably has some other fish in it since it is over 40 years old in its current incarnation and several ponds are upstream and I am pretty sure a BG does not grow to 9" in 12 months. I am assuming all of the fish stocked were fingerlings or something very small, because he mentioned he could not fish it last year since the fish were to small to catch. This is the first time he has stocked it and he has owned it since the early '70's.

FWIW, the HBG could be harvested at your leisure once they are a usable size. Since regular BG were also stocked, the hybrids will have no long term impact on the pond's fish populations. They will be out-bred by the BG (which will outgrow them as well, if managed properly) in short order.

I would continue trying to learn more about what fish are in the pond now before I started doing any culling.

I don't think you can depend much on what the previous owner told you. If it was only 12 months back, I doubt there would be any balance yet, and like you said, who knows about stockings from the past several years.

I would suggest keep fishing the pond with a variety of lures, baits, techniques, etc. and chronicle what you catch. It will give you a better idea of the species you have to contend with. It may also give you a general idea of the different sizes of those species.