No exceptions for holidays or Sundays. The heron, which I've named Perseverance—Percy for short—shows up every morning and evening beside the creek next to our home. I ponder whether the bird has tucked a timetable under its wing like the one I carried in my coat pocket when I rode the Chicago Metra. Fishing is excellent in the beaver pond for Percy to maintain such a schedule.

My husband and I first see Percy sitting atop the barn swallow house before our morning walk when we throw bits of ...