Mine! A mated pair of Tree Swallows have claimed a nesting box on the big pond at Iona Island. Every year, the coming of spring brings these little blue acrobats back from the south. They look very similar to the Violet-green swallows that come back at the same time but the two main differences are that the Violet-greens eyes show completely in the white and the white band extends almost all the way around the base of the tail.