In trying to learn about BFs, saw mention of birds and lizards being a problem. Our close neighbor is a bird watcher and has feeders, etc., and we have really enjoyed the many birds that have appeared since she started feeding. And we have at least 4 very large lizards that live in my landscape beds. So before I get too excited about BF gardening, I'm wondering if the birds and lizards are going to be a major problem?? Already suspect the lizards of one "crime." I was collecting petunia seed for a couple of weeks and then all of a sudden there were no seed pods on the vines. Just vanished! Found that very odd. I removed the vines after petunias were finished and found empty seed pods in neat piles underneath and suspected the lizards because there were no droppings like a mouse or field rat usually leaves.
Butterflies - birds - lizards
Well, there's no such thing as a butterfly predator-free outdoor zone! The eggs, caterpillars and chrysallises are probably killed off even more often than the adult, but all are naturally in danger out in that big scary world. Here's a site showing many of the dangers they face outdoors. But I think any yard which is butterfly-friendly to some extent helps in their survival.
http://www.learnaboutbutterflies.com/Enemies%20of%20Butterflies%202.htm
Oh, wow, my yard has probably more than usual amount of those preditors but I'm going to do my best to provide the right plants and hope for the best. We take a "live and let live approach" and are organic except for fire ant poison (and wasp spray when they build their home on the porch furniture.) I'll be tempted to kill the hornets if I see them eating BFs. But even those are pretty and interesting to watch work. Not long ago we were converting pop-up spinklers to drip irrigation and dug holes to remove sprinkler risers. A hornet started digging holes into the side of those holes and it was amazing how much dirt it moved in a short period of time.
We get more paper wasps than any other kind. Then there's some kind of huge wasp that comes around that nobody has been able to ID as far as the species, but the experts did say it was some kind of Scoliid species. I don't let wasps build their nests on the deck roof any more, but otherwise I mostly leave them alone. Strangely enough, I don't see birds bothering the butterflies or cats here. Of course, it could happen when I'm not around. I usually bring most cats in, but the Gulf Fritillaries are numerous and I don't usually raise them. I squish the spiders that hang around flowers waiting for a free meal from any insect that comes along.
I've got a Red Shouldered hawk family, two hummingbirds, and a boat load of cardinals, blue jays, etc around my house. I still get plenty of cats. Oh, and I've got anoles out the wazoo. I'm actually happy that I've been seeing the native green ones. I haven't seen one eat a caterpillar or butterfly yet. They're kind of lazy. They like to lurk while I'm weeding and when I stir all the bugs up, they move in and eat them up.
Like you, I only use wasp spray and fire ant killer. I've been stung by a paper wasp and bitten too many times by fire ants. They both hurt a lot! Oh, I also kill lubber grasshoppers on sight. : )
Melanie