I understand that a certain number of pounds need to be pulled out per acre per year depending on fertilization, but what about basic overfishing?

Is there a general rule of thumb that x number of hours of fishing per month per acre will begin to have long-term negative effects on the fishing quality of the pond/lake?

Assuming you pull out 30-40 pounds of management fish per year per acre, what about the rest of the fish population? Surely some will get lure shy and tougher to catch. Are there any guidelines, or personal experience with this?