Thanks.
There were quite a few others I didn't edit - notably some nice ones of a sizeable flock of dunlin looking either dark or light depending which side of the birds was turned to wards you. It's amazing how they co-ordinate their flight.
I missed a trick actually. I think there was a great white egret which we spotted whilst walking back to the cars - it's about a mile in each direction to the bird hide. But my camera with its zoom lens was tucked up in its bag. My pal swore she could see black on its wings and wondered if it could be a white stork (most unlikely in Essex, and I think they will still be in Africa anyway), but I think my money is on a great white egret, without being 100% sure. By that time I was looking forward to my cup of tea and bacon butty.