First visit to Dungeness-help identify dragonfly

I visited Dungeness nature reserve yesterday 1st August 2011 for the first time and only had 2 hours to spare there. I had a wonderful time and have got some lovely photos. I will definately be back. Lady in the centre very helpful and two kind gentlemen gave me a lift back to Lydd saving me a long hot walk.

Could someone identify the attached photo for me please.