This is going to depend on whether or not you have lizards or salamanders. Salamanders are amphibians, related to frogs, with a smooth skin like a frog. They are generally quite slow and tend to prefer moist areas. Lizards are reptiles. Generally, they have scaly skin and can move quite a bit faster. Both are opportunistic feeders, and both are very beneficial. Besides the butterflies, they eat almost any insect, including most pests. They salamanders also eat slugs. If there is a way to let these co-exist, please consider it. If not relocating them might be the best option, but you will be removing one of the best natural insect controls around. If they are salamanders, a low
growing prickly, dense border will help repel them. Something on the order of stinging nettle but more controllable. You might also try a screen type barrier around the area, with the top unsupported and allowed to loop back to the outside, but not so much as to reach the ground. When the lizard climbs past the supported area, it folds back the way he came, effectively dumping him back on the ground where he started. A salamander won't be able to climb it. I wish I had more lizards and salamanders here.
Rick
Catlover,
The spiders are very beneficial too. Why kill them? In my garden, they are my first line of defense and we both go out of our way to preserve them. In the
greenhouse, they are my only predator in the winter. I realize you have a few poisonous ones out there but most are harmless.