People often say that spring “bursts” forth. But this seasonal change isn’t like flipping a switch. It’s more like a series of waves breaking slowly. Robins and bluebirds return north in March. During April, more songbirds migrate north from the tropics, adding to spring’s growing chorus. As late as June, birds such as Willow Flycatchers and this Mourning Warbler arrive from South America. By this time, those early robins may be feeding their second brood. For them, spring has been bursting for over three months.
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Spring Bursts Forth – Or Does It?
Written by Bob Sundstrom
This is BirdNote.
We often hear it said that spring “bursts” forth. As if winter’s leafless trees suddenly shimmer with green. Flowers pop. Birds start singing with all their hearts. [Northern Cardinal song, http://macaulaylibrary.org/audio/176244, 0.06-.10.]
But this seasonal change isn't instantaneous. It's a series of waves, slowly breaking waves that sweep up from the south to the north right over the continent.[American Robin http://macaulaylibrary.org/audio/168300]
Early spring migrants like robins and bluebirds return north in March, some even in February. Across the whole of April week by week, new songbird migrants work north from the tropics adding bit by bit to spring’s ever-growing soundtrack
[Intermixed songs of Black-headed Grosbeak, http://macaulaylibrary.org/audio/106598, 0.07-.10; House Wren, http://macaulaylibrary.org/audio/144011, 0.10-.12; Chipping Sparrow, http://macaulaylibrary.org/audio/191234, 0.11-.13].
By May, birds continue flooding into northerly states and Canada. And even as late as June, birds like Willow Flycatchers [song of Willow Flycatcher, http://macaulaylibrary.org/audio/106793] and Mourning Warblers are just completing the trek to northern breeding sites from South America. [Mourning Warbler, http://macaulaylibrary.org/audio/191054, 0.15-.17]
By this time, those early robins… [American Robin song, http://macaulaylibrary.org/audio/168300, 0.7-.11]
…may already be hard at work feeding their second brood. For them, spring has been bursting for over three months.
Today's show brought to you by the Bobolink Foundation.
For BirdNote I’m Mary McCann.
Bird sounds provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Northern Cardinal  recorded by G A Keller; American Robin  Chipping Sparrow  and Eastern Bluebird  recorded by W L Hershberger.
Black-Headed Grosbeak  House Wren  and Willow Flycatcher  recorded by R S Little. Mourning Warbler  recorded by Jay W McGowan.
BirdNote’s theme music was composed and played by Nancy Rumbel and John Kessler.
Producer: John Kessler
Executive Producer: Dominic Black
© 2015 Tune In to Nature.org June 2015 / March 2023
Narrator: Mary McCann
ID# spring-13-2015-6-3 spring-13