to be honest they hit just about anything they can see when they are there so something the lights enhance which would mean bright colored baits in white or chartrouse or dayglo/glow in the dark (self luminescent) would be my first choice, maybe a clear with glitter might work too.
they are below looking up at the lights and eat what they see, the easier it is to see the more action you get.
We were using natural gulps with a 1/4 ounce plain jig head and orange and yellow shad rig . But they were hitting any thing really. In the 3 nights we were there we hooked up with 10 big bull reds , landed 0 . I hooked 4 of them just fishing the trout on top. My son and nephew hooked the other ones on the bottom with live small white trout. Once they got under the bridge it was good night Irene!!!! :(
But it sure was fun , no bugs no hot sun just fun.
im still catching them like crazy in golden meadow so i see no reason theyu shouldnt still be at the bridge.
i think they stay there all the time, they just get thicker at certain times but AFAIK you will always catch them under the lights there in the summer.