Not sure what type of Dragonfly this is but their were one or two flying round the pond on Coombe
I wonder if this is a Black Darter as saw a couple of them on the Wednesday walk yesterday morning flying around but didn't settle and wasn't lucky enough to get a nice photo like this.
Looking on the british-dragonfly web site, I think you might be right, looks like a male Black Darter. I was very lucky we were just sitting on the bench by the pond and they were flying a round when one settled on the grass right in front of me.