birds and garlic

A day or two ago I finally got my garlic planted. This morning I went to look at the chooks, and I saw bits of white where I had planted the garlic. At first I thought it was bits of the skins that I had left, then I realised something had pulled them up.
I planted onion sets last year in the same way and nothing bothered them, so do the birds like garlic more than onions?    It's not like they ate them, so why do they pull them up at all?   

Mine weren't that deep but neither were the sets. I can only think they were attracted to the white of the garlic, more than the coloured onions. 
Why do they pull them up at all? If they had been able to get the onions through the net would they have eaten them?

i planted my garlic start of nov,as they like a good frost and with all the snow  we had it should of done it a  treat.

i ve been very luckly its about 3cm tall now.Its uncovered nothing has yet touched it,but i did put old raspberry canes in the ground as markers to to remember where the garlic was,,,so perhaps this put anything off ,i dunno.

ive had the odd onion set pulled out of the ground when i plant thm, but i just pop them back in ,dont cover them

I thought I saw the culprit this afternoon, as I spottd one of my chooks (the usual escapee) in that area, but on closer inspection the only footprints were on the bare end of the bed, even though some more of the cloves were dug up again. I'm gradually replanting them all a bit deeper. Curiously the ones I planted with the green shoot showing have mainly been left alone.  

I gave up on putting the chook back in the run, as she would only escape again later, anyway. . . Tomorrow she's going in the broody coop!   When I went down at dusk to shut them up for the night I found she has demolished the bed where I planted the strawberries, (which were coming on a treat this morning!), and half of the rhubarb bed.
But the garlic bed is fine!  :blink: