IMO/E LMB don't often go over spill ways... I am betting you have most if not all your original stocker LMB. To help yourself thin out some of your bullheads(BH), consider purchasing or buying a trap. There are several styles out there and they will catch far more BH per hour than you could ever fish out and they work 24/day 7 days a week... Realize that you are going to have a continued challenge as the overflow from other ponds will be a constant battle and you will always be getting new and unwanted guests. You may want to stock another dozen or two LMB in the 8"+ range to assist in controlling the trash fish. You really want to also remove any common carp you have before they get a chance to pull of a spawn.