You make your own luck!
When I arrived at the canal three swans were paddling in front of the bridge. I thought they would look great as foreground interest, I knelt down to my bag to change to a wide lens and planned to walk closer when I heard a whoosh.
I instinctively knew that it was the swans flying. I turned with camera to eye, changed settings, composed and fired off three shots in a matter of seconds still with the long 70-200 lens on camera. Seconds later they had landed at Naas Harbour.
I doubt there'll be any other pictures of Abbey Bridge like this one. Really pleased with this and know I would have kicked myself if the camera was in the bag.