11 in gill is definitely a master angler sized fish. I really don't think your bluegills are your problem. They are the number one forage for your bass, if you aren't catching any small bluegills that maybe your problem. In a quarry type pond there isn't always the greatest bluegill bedding habitat. Do you see lots of bluegill beds in the shallow areas of your pond? Also are there Crappie in it? If so they will directly compete with the bass for food more so than a bluegill. If you have the means start taking out some of the smaller bass and definitely crappie if they are present. Channel catfish can also pose a bit of a problem as well. You could also try stocking some golden shiners as forage, they likely won't last to long but depending on size when stalked wouldn't be eaten by bluegill and crappie, if they are big enough.
