Individual variation is more important with respect to who is more aggressive. In natural setting, most aggressive individuals I have dealt with were Spotted Bass that would bite my hands and mask as I sampled nest for embryos and prolarvae.
In pond setting, the hybrids, regardless of type more aggressive, to point of being stupid. Hence, the term "meanmoouth" from my perspective although one could argue mean = average = in between.
Social setting can impact aggressiveness. Most aggressive males had nest in shallow water while those in deeper water tend to back away when I approach.
Competition outcomes I think has little or nothing to do with gap size. Something way more interesting that does not appear to be in the literature is at play.
