Teaching Baby Songbirds To Sing

[Evelyn Cooper]

Teaching baby songbirds to sing
By:Tina Mitchel, Coaldale, CO
Written with permission
Tina is a licensed rehabber and works part time rehabbing

The birds pour forth their souls in notes
Of rapture from a thousand throats.
William Wordsworth, Devotional Incitements

Somewhere, always, the sun is shining; and somewhere, always, the birds are singing. As spring and summer oscillate between the Northern and Southern Hemispheres, so too does this singing planet pour forth song, like a giant player piano, in the north, then the south, then back again, as it has for the 150 million years since the first birds appeared.
Donald Kroodsma, The singing life of birds.

Bird songs are not just beautiful, entertaining, and up-lifting to the human ear. They also serve a vital function in one of the most basic avian drives: the process of reproduction among songbirds. As one branch of the order of Passerines (perching birds), these marvelous songsters are referred to as “oscines,” from the Latin for “a bird from whose note omens are taken.” Oscines have extraordinary brains that are hard-wired for learning and producing songs. Their double voice boxes—“syringes” in plural; “syrinx” in singular—are complex, with multiple pairs of tiny muscles controlling these dual membranes (Kroodsma, 2005). Think of any lovely bird song you might hear in the spring—some of our native sparrows, any warbler, a finch—and you’re thinking of an oscine. The other major sub-order of Passerines are the “sub-oscines”—rather arrogantly meaning “beneath the songbirds,” implying that they are more primitive. Sub-oscines have much simpler songs, less elaborate syringes, and brains that lack the intricate neural controls needed for complex songs. The most common sub-oscines in the U.S. are the phoebes, kingbirds, pewees, and flycatchers. Oscines generally need to hear and practice their songs in order to develop typical songs while sub-oscines never need to hear even a peep from an adult to produce perfect adult songs. So to be able to sing appropriately as an adult, an American Robin needs to hear other robins singing. But a Western Kingbird doesn’t have to worry about its song as an adult—the song, such as it is, is genetically pre-programmed. The kingbird will produce its song just fine, without any help from human or bird. Pigeons and doves don’t need to hear adult song either. And although hummingbirds aren’t oscines, they also appear to require experience with adult songs when they are growing up.

Birds use songs to establish and defend territories and to attract mates. If baby songbirds don’t hear adult songs during the appropriate learning period—e.g., they are orphaned and raised by a licensed wildlife rehabilitator far from their home environment—they tend to develop simpler songs with fewer frequencies than their parent-raised peers have. Since song complexity and richness attract females to singing males, males with less interesting songs are at a clear disadvantage in the mating game. Even though females of most species don’t sing, they too need exposure to adult songs as they mature or they may not recognize and respond to an appropriate male’s song. Research suggests that babies learn their songs best about 10 – 50 days after hatching. For babies that are raised by rehabbers, though, this prime learning period overlaps with the period that the nestlings are in a rehabber’s care (Dolinsky, 2004). If these baby birds don’t hear appropriate adult songs when they are with a rehabber, they may never be able to successfully compete and reproduce after they are released.

Babies don’t usually develop their adult songs until long after they have fledged. Instead, they pass through several stages as they mature. First is an early sensory stage, where they listen to the songs of adults of their species. They encode only a very specific set of songs, suggesting that they have some kind of a mental template. Next, in the subsong phase, they utter various sounds—much as a toddler babbles all sorts of noises that aren’t quite recognizable as human speech. During the sensory motor phase, they produce bits and pieces of their adult song—but it clearly sounds like a work in progress. Sometimes, in the fall, you might hear a bird song that seems just a bit off. (Was that really a chickadee? Did I just hear a robin? The tone was right, but the rhythm was off…) Those are this year’s kids, honing their songs to match their memories of the adult tutors they heard in their younger days. In the mature phase, they are off and running (well, singing) with a totally recognizable adult song.

Of course, hearing a live bird is the best situation, but youngsters can also learn from recordings (Dolinsky, 2004; Kroodsma, 2005). Baby House Finches, American Robins, Red-winged Blackbirds—or whatever wild birds hang around a rehabber’s yard—will hear plenty of their own songs. But species that are far from home need help to develop their vocal repertoires. At the wildlife rehabilitation center where I volunteer, several of us put together a CD of the songs of our common species—sort of a party mix for baby songbirds. To help us in this effort to give baby birds their songs, the Macaulay Library at Cornell Laboratory of Ornithology (http://www.birds.cornell.edu/MacaulayLibrary/) graciously worked with us to create a CD that contains the western songs of the common species listed above. We set up a simple CD player with speakers in the baby bird room and the bird song tutorials began. And although more exposure is good, even just an occasional playing gives the “kids” a leg up, song-wise.

With all of these songs playing one after another, how on earth does the baby figure out what to learn? It will store only its own songs because its brain filters out all but the relevant pieces. (And if you think of nestlings in the wild, you can picture this for yourself. Surely a great many species of birds sing in various woodlands, fields, and marshes. Babies raised in these areas have no trouble homing in on the right songs in the midst of these those marvelous symphonies!)

Sometimes, people wants to “rescue” baby birds that seem to be abandoned by their parents. Indeed, sometimes nestlings truly need some help and bringing them to a licensed rehabilitator is the best thing. But sometimes people are mistaken about thinking that a nest has been abandoned. For example, the parents aren’t always at the nest, since they need to be out and about, beating the bushes to find food for their growing youngsters. So don’t be in too big a hurry to remove the babies to get some help, thinking it’s always a good thing. Rehabbers can give baby birds nutritious food; a clean, safe environment; and enrichment activities so that they can develop physically and mentally. But nobody will be able to teach these babies their songs better than their parents and the other birds of their species in the area, so that they develop the full complement of skills they’ll need to lead rich, productive adult lives. Before you rush to help nestlings, be sure to contact your local rehabber to get some hints about how to determine when to intervene and when to sit tight for a while.

And if you’re interested in reading a wonderful book about this subject, I highly recommend Kroodsma’s book—a story beautifully told by a man who has dedicated his life to studying bird song.

References
Dolinsky, Melissa B. (2004) Song development in songbirds—Are rehabilitators missing a crucial step? International Wildlife Rehabilitation Council 27th Annual Conference Proceedings, Portland, OR.

Kroodsma, Donald. (2005) The singing life of birds: The art and science of listening to birdsong. Boston: Houghton Mifflin Co.

©2008, Tina Mitchell