I went to Barnes this morning, its a nice reserve (I have some complaints - the food is expensive, the hides are pretty awful for viewing, and some visitors with kids need to read. If it says to not climb on the rocks stop your kids climbing. Don't look on proudly).
There were a number of Widgeon about (a sure sign of winter) quite a few Snipe, both types of Grebes, Green Woodpecker, lots of Hawker Dragonflies and a Water Rail. My personal highlight were two water voles!!