My bet would be a bird. Pulls out the onion, then looks to see if any grubs or worms are exposed in the overturned soil. Haven't ever seen it happen though, just a guess.

My guess would be Ravens, I watch them in the morning where I live and they do have some intelligent habits and are capable of pulling on heavy loads. I watched them pull a platic bag filled with onion sets from a tote bin near where I live.

We do have ravens around, and yesterday while i was planting bedding plants, there were a couple of blue jays in the trees discussing something. "What's she planting now?" "I don't know but it looks good enough to eat!"

DH just mentioned that he's replanted a few as well. Guess we'll have to keep an eye out and see what it is.

The magpies around here pull out anything they can easily pull just because. They are real jokers. I lose a lot of irises that way. Unfortunately they carry them off as well! Blue Jays and Crows are all part of the same family of birds and are also really good pickers. =(

Honalee beat me too it...MAGPIES, the blankity, blank things. I've had them pull out most of a garden of seedlings overnight. So whatever you have in that family, that is most likely your culprit.

Yep! And they will watch you plant it over and over again! Just like the Windex commercial. :0

Magpies, yes, but I also have a problem with robins. I have to replant my peas every year. I watch them through the kitchen window and can't believe that they leave the veggie patch with a worm and a pea in their beaks. C

We do have magpies around, but i haven't seen them lately. Could be them, though - they might be hiding in the bush just waiting. Meanwhile, i guess we just keep replanting onions!

I have many times observed grackles picking my onion greens and marigold blooms. Apparently, they rub pungently scented leaves, flowers and insects through their feathers for parasite control. I don't know if magpies exhibit the same behavior. Good luck with the replanting!