Mealworms are actually the larvae form of the black mealworm beetle, Tenebrio molitor, a darkling beetle. I'll let you google this species if you want to know more. The second description I read on care and feeding also included preparation for human consumption, which abruptly ended my interest. I'm in this for the birds!
Links and resources:
For articles leading up to the bluebird family posts, visit my Wild Birds Unlimited articles: Smitten with Bluebirds and April Celebrations. And to see the phoebe female nest building, visit: The Hard Work of Nesting.
Find instructions for making nest box predator guards by clicking the link. These guards have worked to keep the 9" arm of a raccoon out and have prevented prowling cat predation, as well as snakes. A 7-inch depth is recommended. You may also find a version of these guards at the Wild Birds Unlimited store nearest you.
The "meal worm feeder" you see in my bluebird family blog posts is available through Wild Birds Unlimited.
Upcoming: A very attentive parent and bluebirds loving water