Try This

Oneputt

Whilst walking at Lackford Lakes (Suffolk Wildlife Trust) we could hear a woodpecker tapping but couldn't see it so I picked up a stone and tapped on a tree.  Each time I did this the woodpecker replied.  Eventually a great spotted appeared on an adjacent tree.  I was a little suprised at the result as normally I would expect this to happen in Spring when they are at their most territorial