Unusual bird behaviour in daughters garden while I was on grandparent duties!

My wife first drew my attention to a male Green Woodpecker in the garden apparently looking for ants.  I then noticed a Blackbird, Robin and Great Tit sunning themselves in the same small area of bare earth.  The sun was out at the time and the garden faces west.  I have previously seen birds sunning themselves but not in the manner of three species together.  A short time later when I looked out again... two Woodpigeons had replaced the three birds and were also enjoying the sun.  Alas no picture of the GW.