WB would eat small BG, but are they going to make any appreciable difference by trimming large numbers of small BG? I doubt it. Weissguy on here has some WB in his 12 acre lake. He says they chase the schools of GSH up and down his lake. Just like HSB, they are more open water fish and wouldn't be sharing the same habitat as BG very often. Bringing WB into your pond from the wild will carry risks... Disease, parasites and other hitch hikers. I'd skip them unless you really wanna experiment, but I think you'll find they aren't gonna help with your goal of growing trophy BG.