Thanks again Bobby
I've been practicing at home and have a new approach for the weekend. I'll turn the flash down and shoot at a lower shutter speed. I t was really dark andI couldn't even make out the colour of the birds. I was shooting at a very high shutter speed and all the pictures came out dark. I then used ps to lighten them. When I viewed the pictures on the camera, they all looked fine but on the computer they were very dark.
Can't wait for the weekend!