i also live in So Cal, and every year it takes the male Orioles some time to learn that they can access the hummingbird crack from my feeders without pulling off the bee guards.
my wife is amused by the fact that the female Orioles realize almost immediately that they can perch on the top of the flower cup and drink their fill but the males don't.
there is a lesson there somewhere.
How wonderful that this website provides replacement parts for one of Perky Pet's ever-popular pinch-waist 8oz glass hummie feeder. These bee guards for the model 203C/CP are crucial for keeping the bees out of the flower ports and the hummies can still get thier long tongues easily through the bee guard grids. We haven't had any bee swarms since incorporating the bee guards along with the use of a Perky Pet AntGuard. The AntGuard (fumes?) seems to repell the bees while the bee guards keep them from reaching/touching the syrup in the flower port. Before using these bee guards, tiny bees/wasps would get trapped inside the syrup and I was always washing half-dead insects out of the feeders. Don't have that problem any more!