The Mysteries of Songbird Migration

(SOUNDBITE OF CHIRPING BIRDIES)

ROBERT SIEGEL, Host:

Those are Bobolinks, courtesy of the Cornell Laboratory of Ornithology, where Miyoko Chu works. We've invited Dr. Chu, who is the author of SONGBIRD JOURNEYS, to join us because Saturday is International Migratory Bird Day. Welcome to the program, Dr. Chu.

MIYOKO CHU: Thank you.

SIEGEL: First in this spring season, which songbirds are flying north?

CHU: Well, there are Bobolinks like the ones you just heard as well as dozens of other species that are coming from as far away as South America, Central America, Mexico and the Caribbean and will be adding their own beautiful songs to our landscape as they come.

SIEGEL: I was surprised in reading what you've written about, migratory songbirds, how little ornithologists actually know about their migrations.

CHU: Yes, it might seem surprising because songbirds are so familiar to us. We can just walk out into our urban parks, our yards and there they are, singing, colorful and beautiful up close. But one really tough thing about studying them is that they're so incredibly mobile. They live out their lives across thousands of miles over the year and because a lot of these songbirds migrate at night, it's impossible to see them as they're actually traveling.

SIEGEL: They're flying pretty high up in the air actually.

CHU: They can fly, yes, thousands of feet high and they'd be tiny, tiny specks and we wouldn't be able to see them by day for the most part anyway. But the fact that they're going under cover of darkness, taking off after sunset, shrouds their migration in even more mystery.

SIEGEL: Some of the things that we know about migrating birds, I gather from reading from what you've written, we know because of the phenomenon known as a fallout, something I've never heard in this context. But I gather fallout is a very common word to birders.

CHU: It is and it's an exciting word to birders. It's something they wait for all year long. In spring, when weather conditions are right and at certain locations where geographical features converge to make it very appealing for birds to land, especially in an emergency situations, you can get amazing concentrations of birds, even in urban parks like Central Park in New York, where the birds come down to rest as they're going through this long migration.

SIEGEL: These migrations are thousands of miles long and these birds, at least the ones who survive the journey, will make it, do we think twice in a lifetime or three or four times in a lifetime? How often might a bird fly from South America to Central Park?

CHU: Well the really lucky birds, the long-lived birds that somehow survive this can do it over and over. The Bobolink you heard singing will often return to the exact same spot where it bred the previous year. And there is one Bobolink that is 9-years-old. Scientists estimated that it had flown the equivalent distance of four and a half times around the world in its lifetime.

But most Bobolinks and most songbirds aren't that lucky because migration is a hard life and it's tough to be a songbird in general. And so most don't live beyond two years.

SIEGEL: Well what are you doing for International Migratory Bird Day?

CHU: I'll be out birding with my kids and husband and also just thinking about these amazing birds and hoping that people will realize that as these places are so connected and so important to these creatures that we try to preserve as much of it as we kind.

SIEGEL: Well Miyoko Chu, thank you very much for talking with us.

CHU: Thank you.

SIEGEL: That's Dr. Miyoko Chu, author of SONGBIRD JOURNEYS: FOUR SEASONS IN THE LIVES OF MIGRATORY BIRDS. She's also the editor of the newsletter Birdscope at the Cornell Laboratory of Ornithology. Dr. Chu says that she'll be looking and listening for this bird tomorrow, the American Redstart.

(SOUNDBITE OF CHIRPING AMERICAN REDSTART)

SIEGEL: You can hear more bird songs and nocturnal flight calls at our web site, NPR.org. Transcript provided by NPR, Copyright National Public Radio.