The larger lake with bigger harder to catch BG likely has a more diverse habitat providing a better food web (food items). Harder to catch BG in the larger lake I think indicates the BG are fewer per acre (good predation of the optimum size class of BG) and possibly has clearer water allowing the adult BG to easier to see baited hook/line vs real food.
Number of pounds of BG that can be harvested from a well managed 0.5 ac pond will be mostly dependent on if BG are fed high protein pellets. Pellet feeding produces bigger BG quicker and more BG per acre. Adequate predation and proper harvest maintains the high quality fishery. I think BG harvest guidelines have been discussed in a couple threads in the Common Pond Q&A Archives of this link for growing big bluegill:
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=189988#Post189988And an Archive thread about wise harvest of bluegill from lakes and ponds.
http://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=431667&#Post431667The general guideline for panfish harvest is to remove 20% to 30% of the harvestable adults which research has shown will be the annual natural mortality of old individuals. The number that comprises the 20%-30% will be determined by the productivity and management of selective harvest.
From my experience and best guess, a fertile pond in limestone soils with a good algae bloom (18"-2.8ft vis) will produce about 200-260 lbs of total BG per acre which remember includes a lot of smaller (2.5"-5.5") individuals who are important to fill the gap of those harvested. A good algae bloom consists mostly of algae - zooplankton and not primarily suspended detritus, silt/clay particles that also reduce visibility (Secchi measurement) and presence of non-plankton particulates have been proven to significantly suppress plankton blooms and overall productivity.
Clearer less fertile water (vis 4ft-7ft) will result in one half or fewer BG lbs per acre (abt 80-100 lbs/ac). The smaller(2.5"-5.5") BG in both situations of bloom and clear could easily comprise 70% of the total BG density. Special management ('selective harvest' of natural & manual, and predator density) could skew the number of larger BG from 25%-30% to somewhat higher percentage to possibly 40%-50% of the total BG density. I know from experience this is true with yellow perch populations.
Pellet feeding and aeration could boost the total pounds of BG per acre to 400 maybe 500lbs/ac which would allow a larger annual harvest possibly 100-130 adult BG (7"-9")per acre. The actual number of BG harvested will depend on their total weight (average and total) more than just BG number/acre. Selective harvest methods can skew the average size of the BG present for harvest.
IMO the better the quality of pelleted food (protein) used will produce more better quality BG faster than cheaper average quality fish food (32%protein). Remember in a higher production system your crop will depend on the quality of food it receives. Some fish foods have been proven to have higher digestibility, produce more body mass, and better growth improvements with less waste per pound of pellets fed.
