Yup, those are Monarchs. And yes, some birds will try to eat them, but usually learn the lesson the hard way that they do not taste good. I don't bother with trying to keep the leaves moist or any of that. Monarchs eat so fast I never have a problem with the leaves drying out. I just try to give them as much as they can eat in a day or so and make sure to keep the container clean and give them fresh food once or twice a day. Or you can leave them on the plant, if you want. Monarchs tend to have better rates of survival, but are still at risk for OE spores, viruses, bacteria, spiders, lizards, and other predators.