I grew up on the Chesapeake (Annapolis area) fishing a lot of ponds like yours and also a lot of back rivers. For sure there are white perch in there, they are the tidal mid-atlantic's version of green sunfish. I would imagine that river is chock-full of them.

They are actually really fun to catch on light tackle. If your fishing bait I would try to get my hands on some grass shrimp or blood-worms. Bucktails work well and the aforementioned chartreuse grub...Try docks, sea walls, and any underwater structure...the rockier the better.

As CJB said the real fishing is just across the wall. Anyway I think you got the best of both worlds there. Enjoy the bass, could they be bigger? Of course, but I think they'll do fine supplementing the world class CBBT fishing.