Program Information — Series 3 & 4
Click on a program in the right-hand column to see a description and program notes.

Local Dialects

Song dialects are common among songbirds who learn their songs from others in their neighborhood. Some of these regions can be large some quite small.

The classic case of small local dialect areas comes from the Marin headlands, just north of San Francisco, after periodic wildfires destroy songbird habitat. As a patch of suitable habitat regrows, white-crowned sparrows move back in. These patches start small, with a founder pair of birds. As their offspring grow up, they learn the father's way of singing the species song, then either leave or stay to colonize adjacent territories as the patch of chaparral grows. In other parts of the headlands, other patches are colonized by other founders, who pass of their song variant to their offspring, some of whom move in nearby.

As the patches of habitat grow, each is an expanding island where the founder's song is reproduced. And when the patches grow back together, sharp boundaries remain between the areas where each song variation is sung. Some ornithologists speculate that the song variant serves to isolate the groups reproductively ... not that they can't breed across song variants, but that they choose not to.

Donald Kroodsma describes an imaginary walk through the Marin headlands in The Singing Life of Birds.

Chris Tenney recorded the white-crowned sparrow I use to introduce this program in the Sierra Nevadas. The recordings of the post-wildfire white-crowned sparrow dialects on the Marin headlands can be found on the CD accompanying Donald Kroodsma's wonderful book The Singing Life of Birds.

Series 3
Egg Calls
Chick ID Calls
Chicken Calls
Vocal Tract
Syrinx Styles
Airway Model
Airway Overtones
Coiled Trachea
Beak & Airway
Vowels & Airway
Tuvan Throat Singing

Series 4
Size & Sound
Forest Soundscape
Grassland Soundscape
Bird Hearing
Local Dialects
Regional Dialects
Drumming - Woodpeckers Etc.
Bird Tongues
Bird Brains & Singing
Song Duels?
Dawn Chorus
Finale: Song Sparrow