Mine do. I don't know about the red wigglers that I have loose but when they see a mealy beetle or super worm on the loose they pounce on it. I haven't seen them digging for worms in the soil of the tank but in the food bowl they know there are supposed to be worms and they clean up every last one. If all aren't eaten the first day they are gone by the time I go around with the worms again. Sometimes, since I have so many girls, I will go around and feed each one individually by hand and then I dump extras in the bowl. As soon as the worms start hitting the bowl I have girls jumping down and running for the dish.
I guess they are really conditioned to this type of feeding arrangement. It may just take some time for Erowen to work this out. You have only had her 4-5 months and I have had mine for 2 or more years. Give her time! She'll adjust to your routines. 
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Marcia - FroggieB Dragons
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