The nestbox and water is what will attract them more than the feeder, since bluebirds are not generally “feeder birds”. Most of us have had to teach our bluebirds to come to our mealworm feeders by gradually introducing them to it, so that’s more of a process. If you put your nestbox in a desirable location (see Nestbox location tips you stand a good chance of attracting them, but it may take time, and you will have to be patient.
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