I'll defer to Eric on the quantity of forage to supplement. I agree with him that you need good representation of forage 2-3" in length.
With regard to removing some of the "too big to eat" BG to balance forage supplementation. Yes, I think that is wise. You've fed all season and you have very likely boosted the standing weights above the natural carry. Adding an additional weight of consumable prey for the water to carry over winter should probably be accompanied by removal of a similar weight of non-consumable prey fish. That way .... the forage adults in your pond will not have to endure more food shortage (over winter) than they would have if you hadn't added the forage. IMHO, you can remove more than that and get benefits of better production of YOY next year than if you harvested none. Many do not agree with me about that ... they would rather stock/sell more BG that can reproduce so that there will be more spawning.
Anyways, good management always looks forward and seeks to make the present condition appropriate for the gains sought for the next 12 months. Late Summer, Early Fall is a great time to do that. You really have 3 tools at your disposal. Removal of underperforming or unwanted LMB, limited harvest of BG to open carry for next year's YOY recruitment and improve overwintering condition of forage broodfish, and lastly supplementation of forage. The forage supplement should seek to supply the population numbers and biomass for which the pond is deficient of ... either for overwintering or potentially for the subsequent 12 months.
bstone, you are behind the curve on population management ... if ... you haven't removed any LMB and want to maintain an LMB standing weight below 80 lbs/acre. Got to get on that or the amount forage you will need to supplement to keep them growing will be cost prohibitive or possibly elevate standing weights to dangerous levels. Your LMB can essentially double in weight at their current size over the next 12 months and it's a good idea to make some room for them to grow with forage your pond is already making. You could take as much as 1/2 of the population of LMB. Were the pond mine, I would remove around 50 LMB from those 2 acres. For sure, I'd remove any caught that are less than 1.2 lbs in weight and as many as I could while the water is warm enough to have a good bite.
