I wondered about that, knowing that your bird was native to that area. The information I was given listed your residence as "U.S.". We have regulations here that prevent us from keeping wild animals, even orphans, as pets without a permit from the state. I'm not sure of the rules there, but it is something you may want to find out about to avoid a problem.
Ibis are primarily carnivorous, so you're right on-track with earthworms. However, it's good to offer a bit of variety to be sure Heidi is receiving all the nutrients she needs as she's growing. Dry dog food or cat food, soaked in water, should be readily accepted. Beef or mutton heart is a particularly good source of high quality protein and other nutrients. This can be cut into small cubes and fed raw. Any kind of fish, shrimp, or small reptiles may be especially welcomed and will help her learn what kinds of food for which to forage on her own. Be careful when in close quarters with her as she matures, since Hadedas may become a bit rowdy, especially at feeding time. Wearing eye protection when handling her would be a good idea to help avoid possible injuries. Vitamin and mineral powders can be added to her food to assure proper nutrition. You should be able to purchase these from poultry supply stores or online. A vitamin A and K supplement plus a mineral supplement should do just fine, use as the package directs for chickens - it's the same dose for both. Hopefully I've covered everything, but if you should have any additional questions, please let me know, I'll be happy to answer them for you.
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