Oh dear

Would not want them in my garden for sure.

Uh Oh!!!!!!

I'm not sure what they're eating but there seem to be quite a few of them and they're everywhere! I've been spraying with a Bacillus thuringiensis solution that worked quite well last year on the sensitive ferns & on the Oriental fruit moth larvae that have ruined my peach crop 2 years in a row.
I also used a mixture of sesame oil and fish oil that was very effective. I got it at Home Depot. The only problem is it makes your garden smell like fish for a few hours. I'm surprised it didn't attract every cat in the neighborhood. But it's safe and harmless to birds, beneficial insects, bees and amphibians so I was happy to find it.

That is never good to see! The BT solution is a good choice though. Were you able to catch them before any damage was done?