Help! How do I figure out what's eating my veggies?

I am having a problem with my first Colorado garden. After serious groundhog problems in NJ, I planned ahead with this garden--it is attached to the house, with the outside surrounded by a stone wall (buried pretty far down) 3-4' high, topped with a wood lattice fence to get the height to about 5 '. Veggies are all in raised beds (landscape fabric underneath) with crushed stone mulch between. Most of the veggies are doing great, including mature lettuces and beets that are untouched. However, there's evidence of sporadic munching--mature bush bean plants (only a few) look bitten off at the top, as do several foundering cuke plants (their failure is another story). Squashes, cukes, and eggplants looked bitten off at the top early on, like at 1-2" high. Recent replants for fall of lettuce and spinach and beets also got nipped, these mostly at ground level. Finally, a parsley plant had all its leaves nipped off. Meanwhile, lots of things, even those closer to the perimeter, are untouched--basil, cilantro, tomatoes, peppers, most of the beans, and the larger lettuces. EEK! Losses are tolerable so far, but I fear widespread problems if I don't figure it out. Can birds do this? Grasshopper like bugs? I haven't seen any beetles, but wonder if they do this kind of damage. Haven't seen any evidence of rabbits inside either. We have deer in the yard but I don't think they'll get into this enclosed area so close to the house, and I've seen no evidence of them (they could probably consume the whole garden in one night? No slugs seen... Short of night-goggle or video surveillance, what to do? PLEASE HELP!

Sure sounds like deer and/or rabbits. (Parsley plant's demise is what makes me think so.)

I tried some red pepper sprinkled on those veggies that a rabbit nibbled on. I have had no more trouble. I am not saying this is a sure cure [for a while at least] but it might help.

I've had good success with hot pepper wax spray. I tried garlic and red pepper flakes. Had some success for a while. Shake-Away seemed to ATTRACT varmints, if anything.

The deer and rabbits have had a buffet in my garden. The deer seem to nip off the tops of the plants. I've got my 2nd stand of corn up to about 1 ft. tall and they keep biting it back. Green beans earlier, same thing. I can see their hoof tracks in my garden after I water and ground is soft.

The rabbits have been a real pest too. They eat off the blossoms from my cukes, cantelopes and watermelons before they can even have a chance to make a fruit. I finally trellised some of them up off the ground and am just now starting to get a few.

Last year we didn't have deer problems. I used some bedding from some local horse barns for mulch. I read that deer won't graze where horses graze for some reason. Maybe that had something to do with it? I guess I need to go get some more, as it had horse manure in it also.

My daughter works at a dog grooming shop and she says that a lady comes in every spring and asks for a trash bag full of dog hair clippings to put in her garden. She says it works to keep rabbits out. She mulches all around her plants with it. A phone call to any dog groomer would probably get you some if you wanted. I got a big bag, but haven't tried it yet. It's almost after the fact now, getting hot and everything is about to burn up anyway. After the struggle this year, I'm going to try it next for sure.

Liquid Fence® (There are others that claim to do the same thing, but I've seen this one work. Don't use a substitute.)

HTH

The deer and rabbits have eaten everything they can get to(Beans,Sweet Potatoes,peas okra, etc.) I stumbled on to a home made repelent that has been working for the last two weeks. 1 cup of milk (at least 2%) and the white of one egg per gallon of water. Mix in pump sprayer and spray new growth as it emerges.
Does not smell bad to us and washes off easy, but deer,rabbits etc, do not like the smell and taste of protein. It works!