Birds digging up my House Leeks?

I planted my House Leeks in 2 places in the garden where not much grow and adding some to a trough few months ago. They were looking great and were beginning to spread... until last week!
My husband found the empty trough one morning with a scattering of bits of succulents and soil all over the path.
This morning we noticed that the succulents growing in the garden have been pulled out and tossed to one side- again with their leaves bitten off.

First it was the red beetle devouring my lilies and now it looks like the birds may be feasting on my plants!
"I am wandering if the birds are getting their own back as we have taken away our dogs water bowl as the birds were leaving their poop in the water"

If I could have found a devils icon on this thread it would be plastered here --

 

Its usually black birds I find that do this.
They are looking for insects hiding under the plants, they rake all the moss out of the house and shed guttering as well, throwing it all over the place.

They seem to do it more in dry weather, presumably they have hungry mouths to feed.

 

Blackbirds do the same for us too.