Debbie:

Go out there late at night with a flashlight. It might be earwigs (pincer bugs).

Applenut

The most common "eater" of rose leaves in California is the Bristly Rose Slug, the larvae of the Rose Sawfly. The sawfly is a pudgy little wasp. It lays its eggs on the UNDERSIDES of the leaves and the caterpillars feed on the UNDERSIDES of the leaves.

The rose slug is tiny, no more than 1/4-inch long and very slender, and it's the exact same pale green as the undersides of the leaves. Talk about hard to see and find!

It's the critter that "skelotinizes" rose leaves.

It's pretty easy to get rid of, actually. Almost any good spray will do the job: insecticidal soap, Neem, pyrethrum. The trick is to spray thoroughly UNDER the leaves. Not stand back and spray all over. You have to get UNDER the leaves.

By the way, a commonly suggested spray for rose sawfly is BT. It doesn't work. It doesn't work because it's meant for the caterpillars of moths and butterflies. The rose slug is the larvae of a wasp.

And I'm not sure of any beneficial insect that preys upon it.

As for your rose buds, Applenut has a good idea. Go outside late at night with a flashlight. The critter most likely is an earwig, sowbug or pillbug. It also might be a slug or snail.

Joe