Bill,
The initial forage potential may be and probably is in the neighborhood of your estimate. The weight of LMB supported seemed low for the LMB supplemented. Thank you for calculating the weight of LMB initially stocked. So if the standing weight of LMB is 48 lbs/acre, just shy of 250 lbs of forage is needed to maintain their weight over the next 12 months. Probably not a problem if the pond can produce a high proportion of that consumption. But if we expect the carry for LMB to be 5-10 lbs/acre, then there is a significant under-supply of forage. Enough, under supply of forage that mortality would necessarily do some balancing.
So what should the OP do? The BOW will balance naturally through mortality. Other options would be to remove some LMB and/or increase the forage potential through feeding. FWIW, I understand the OP doesn't want to feed supplementally ... but it is an option considering the BOW will be accumulating nutrients anyway. An acceptable boost with a plan of weening the pond off feed might be something he would consider.
