The bird reserve

It was the last day that my sister RJS is in the country so we went out on the Wash to the bird reserve. The tripod, however, never came out of its bag! I took a few shots before the battery ran out and then found the second charged battery had almost run out too. So is it best to charge a second battery and remove it from the charger till needed or just leave it in the charger till it is required? I knew the batteries on this camera were not that good but I did not anticipate a problem if I carried a spare! Anyway, I got a few reasonable shots of the reserve including what I think is a little egret. I missed taking shots of the terns hovering against the breeze and diving into the water for insects so I will have to go back another day. I have played around with the shot I chose to try to give the atmosphere of the place. Best LARGE.