For the last couple of years we have had two wood pigeons coming into our garden ,they were always at it on the fence ,thats how i noticed them ) ,but a few weeks back i looked out the window and a sparrow hawk was killing a bird on our lawn ,i went hysterical but couldn't do anything,all that was left were feathers.Next day I noticed 1 wood pigeon on its own,I knew then which bird the hawk had killed,I felt so sorry for the pigeon sat on the fence on his (or her) own.