It gets worse. Gulf Fritillary, Zebra Swallowtail, Cloudless Sulphur and others get their nutrients from manure. And the Pipevine Swallowtail likes the taste of maggot too. Oh, and the question about rotting fruit and ants. Put the fruit in a bowl, set the bowl in a large tray of water. The moat of water will keep the ants at bay.
I like the Coconut Shell,..the natural look,..and nice idea to leave out water for the Butterfly,..Cheryl you do make use of everything,..well done!. Sooooo,.. leave out a small mound of manure,..an egg cup full of Maggots,.."preference to white ones",..and some rotten fruit,..and behold!.
I think I'll stick with the stale beer and soda, if you all don't mind! :-D For rotting fruit... they can visit the compost pile on their own.