Today as I biked to my office at the Smithsonian, I heard a Gray Catbird calling from a patch of shrubs next to the museum. This is a species that, before long, will probably head south, as far as Mexico or the Caribbean, for the winter.

To me, hearing the voice of that wild creature made my morning just a little bit sweeter. I think of these migrant songbirds as little messengers of joy, bringing a peaceful pleasure to all who take note of them in their daily lives.

Gray Catbird, Paul Sparks/Shutterstock

Fall migration is cryptic and quiet, and requires focused attention from the observer. I do this by heading to Cape May, N.J., and spending several days there beating the bushes with my favorite birding friends. Having a special place to go in the fall makes it all worthwhile.

Sentinels of Winter

The Yellow-rumped Warbler, which I prefer to call Myrtle Warbler, floods the thickets of the Atlantic beaches in October and November. They are the sentinels of winter, with their somber autumn plumage and ever-present call notes punctuating the shortening autumn days.

Yellow-rumped Warbler, Larsek/Shutterstock

Earlier this year, I went on a three-month road trip from Texas to Canada, traveling north with these and other songbirds as they made their spring migration. I am planning, in a year or two, to take the journey south. It will be an entirely different experience, following a different route, because the autumn phenomenon is so different from that of the spring. I will focus on a series of migrant traps, like Cape May, and the question is where to end my journey. Perhaps Cuba?

The bittersweet quality of autumn, with its hint of mortality, makes fall migration a time of reflection. The birds' journeys are arduous. How can a tiny creature, weighing less than a McDonald's hamburger, born in early June in Ontario, make its way south to an appropriate wintering habitat in a place like Colombia—without an iPhone and Google Maps?

That's a miracle!

Dr. Bruce Beehler, an ornithologist, conservationist, and naturalist, is a Research Associate in the Division of Birds at the Smithsonian Institution's National Museum of Natural History. He has published 10 books and authored scores of technical and popular articles about nature. In 2007, Beehler was featured in a "60 Minutes" piece highlighting an expedition he led to the Foja Mountains in the interior of New Guinea, where scores of new species were discovered.