The Birds and the Scarecrow

I have a hay bale on my back porch that I use to practice my spear toss.  It's wrapped in plastic to help hold the hay in and keep it from going everywhere.  Today, I noticed several birds sitting on top of it, shoving their beaks through the holes torn by my spear, and pulling out the hay.  I think they're using it to make a nest somewhere, but I can't be sure.  They may just be messing with me.  Watching them rip the hay out of my bale was like watching the flying monkeys dismantle the scarecrow.  There's pieces of him everywhere.  I guess I'll have to try to put him back together again when they're through.