Thanks guys.

Bill I agree that a major factor is room and habitat. That is how much room is needed to offset the competition. I was being more general in the question. The question in my mind and as reflected in Dave's answer, is how much room (vertical and horizontal) and habitat does it take (where is the point reached). A simple question but not a simple answer ( as in one factor) or reason (complicated set of variables).

I will look back at those SMB spawning studies to see if LMB were present and the size of the lakes. They were not overly large as in thousands of acres but still had good recruitment. I don't recall if LMB were there.

Sunil may be on the right track but he has smart SMB that are big enough to eat small LMB.