No it is not legal, any bait home raised or anything out of your tank should not be entering any parts of the water in California. When you buy live crickets from the bait shop, they give you a receipt for a reason so you won't get cited. Been fishing up and down California delta, lakes, rivers, and piers/beaches since the last time I can remember anything dealing with fishing.
If home grown/raised crickets is legal, then that would be to say that home bred bluegill is legal. But no it isn't legal at all so I would highly advise you to be aware with it. The reason why it is not legal because of the fear with some sort of parasites or anything that enter in the water may possible cause some danger into the ecosystem. And they don't know what can possibly enter the water, it can be anything.
One example is the carp disease at Clear Lake a few years back. Fortunately some dumb idiots released a few koi into Clear Lake, which the koi is full of diseases and parasites. Almost every single carp left to right up and down anywhere in the lake you name it. They all died because of a few koi was being released into the lake. Although non of the other species were harm at all, but carp almost went extinct in Clear Lake. Now I go fishing at Clear Lake, the number of carp is dramatically down before the carp killing spree diseases that occurred in Clear Lake.
Please don't get yourself in trouble by the warden for something you thought it is correct. And don't fight back with a warden saying you are right and they wrong, they will pull out the Fish and Game Regulation Book and fight back at you. Unless you know exactly what is being said in the booklet, you can do your thing against warden. Just be aware and don't use anything home bred/raised or even a bluegill you caught at the river/lake that you took home and take it out the next morning.
As far as bluegill goes, the only safe measure is that the bluegill is freeze over night which will get rid most of the dangerous infestation parasites. Keep in mind that certain lake may run its own law in terms of using bluegill as live bait or even for just for bait. Such as Lake Amador, it is illegal to catch a bluegill to use for bait or even bring a frozen bluegill at home to use for bait. I don't know why by the law is the law and no one can override it legally. Happy fishing and tight lines...
