Could have been the bird was after a bug that was crawling across your plants at the time. Alternatively, it may have wanted some of your potting medium as nesting material, though it's an odd time of year for nest building. If it was perched on a leaf it could possibly cause that kind of damage.

I had a problem with a couple phals I had outside earlier this year too. Something came along while I was at work and nibbled off the green tips of my arial roots. :(

I keep my Phals indoors at night during the middle part of August. I learned a few years ago that Maryland has monster moths or something similar that gobble up tender phal leaves overnight.

--Stitz--

Mehitabel, I have no useful suggestions for you. However, I want to say my problem is the other way around, my phals are vandalizing the birds. Will make a seperate post, lol.
I think they are going for the sphag or twigs if they are around.

Blue Jays and the fledglings of the Robins, Starlings, Grackles and BJs have all been seen poking around the orchids every year here. Last year the Carolina Wrens made a nest in a tray of orchids.

I think the youngster birds damage the plants out of curiosity or just something to do. The little hoodlums!

The most problem I usually have from them is they take the ID tags out. On rare occasion I've had the whole plant pulled!

The great outdoors has its risks, fer sure!

All I can think would be to put up some bird netting, if possible, to protect your plants if you can.

C3D

Are you sure the damage happened after dark? Most birds are not active at night and are roosting.

I would be more inclined to think it is some kind of insect damage. Grasshoppers and caterpillars are famous for chewing on leaves.

Brooke

I agree with Brooke... most night vandals are insects or slugs and the like. The only things flying after dark are bats and owls, and they don't usually go for plants.

Throwing some netting over the plants at night might help...

I agree with Brooke and jodik. Night preying insects are probably more to blame. You might try policing the plants at night with a flashlight to see if you catch anything.

Also, ground hogs have shown an interest in my orchids, but they don't bite them for food, they just bite them and leave the pieces where they drop!

Yes, birds roost at night. But they are going at dawn, and I'm not out there til 8 or 8:30. That gives them several hourse of fun uninhibited by cats or humans.

Some of the scratches are three equidistant scratches. I can see how raking a bird claw across might do that. A little mystifying how slugs could manage that :)

I vote for birds.

Chick, the mockingbird had two babies in tow when I saw them, so probably those fat and sassy younguns.

Can cats get onto your balcony? I have 2 and they occasionally show an interest in my orchids. One phal has several scratches on the leaf from being batted at. A Pot has a few holes from being bitten. An onc has the tip of a leaf shreded from either a swipe or grabbing it in their teeth and pulling. Cats like to eat plants and and even orchids can peak their interests.

beer in a bowl, I bet that it'll either net you some thing small or at least give you an idea of what the size of your problem is, just make sure that there is enough room between the container used and the liquid so the insect(if it is one)cant climb out.

Gaston

I hand fed a baby Oriole she was on the screen porch learning to fly before being moved outside . Did a number on some of the plants going up and down the leaves looking for insects with her sharp beak .I named her Twiddle . :) Gin

Hey, Gin. I'm pretty sure something like that happened with the mocking bird babies, because the last three nights I've kept the orchids in the middle of the deck away from the bannister, and there's been no damage.

I don't think insects need to walk along the bannister to get at plants.

Sounds like you enjoyed knowing that little Oriole baby. :)

Been there, actually saw them snatch phal seedlings and fly off. The new leaves must be tasty. I but chicken wire over the seedlings after that, never had a problem with big plants