The next day the clouds moved in. I drove east to Petrie Island in search of marsh birds and migrants. When I stopped by the marsh along the causeway, however, the water levels were still high. I didn’t hear or see any rails, bitterns or Marsh Wrens; there were a few mallards and Tree Swallows, a single Great Blue Heron and that was about it. A couple of Yellow Warblers were singing in the shrubs and a pair of Red-wings were mating on the ground. Then I noticed a dark bird flying over the water on the other side of the causeway; it was my first confirmed Black Tern in Ottawa! I watched its graceful flight for a while before it vanished over the marsh.