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Recently, while listening to the jumbled bursts of song at first-light, it came to me that after some 140 Bear Valley Springs CUB columns, we have not previously explored the Dawn Chorus. Further, since in May/June this frenzy may begin as early as 4 AM, we suspect some of you may never even have heard the Dawn Chorus! Well, it’s time to explore this choral event, and it’s time for all of you to get out and listen to this early morning cacophony.
Other than a quick overview, we will not venture deeply into the complex physiology and functioning of a bird’s vocalization structure. Bird calls and songs are not a function of the larynx (this is used for breathing). Rather, for birds, a structure, the syrinx, is the voice box. This structure is a pair of chambers located along the trachea where it splits to form the two bronchi heading to the lungs. Held open by rings of cartilage, the muscles of the syrinx control the details of song production.
There are birds which have no syrinx (turkey vultures for example). Many species, although having a voice box, communicate by also producing a variety of sounds. The drumming of woodpeckers, the winnowing of common snipe and the drumming of ruffed grouse are just a few species and methods. Body language is also a common means of communication. Here, though, we speak of the songs of song birds – suborder Passeri, the oscines, or true song birds.
At 4:30 AM, even before the last Nightjar shuts down and the last owl stops hooting (or barking), in an Incense Cedar Tree right outside our bedroom window, a valley quail loudly and sharply yells a sharp wik. This call continues for a while, then the male sings out quid pro quo. Really! In fact we have a male which sings out Neb-ras-ka. Another says Ar-kan-sas. Oh yes, a few do sound like Chi-cag-o. But these birds are non-oscines!
Soon though, the true song bird accentuated Dawn Chorus begins. Our nesting Ravens begin croaking, the Black-headed Grosbeaks are off and rambling with their drunken sing-song warbling, a nesting Oak Titmouse gives a strong four note call, Bullock’s Orioles begin their whistling song, and finally Steller's and Western Scrub Jays are sassing and yelling at everyone. It’s past first light, it’s dawn and Little Brown Bats are fluttering into their box beneath the roof’s overhang.
Better yet, let’s join a recent TMBC bird walk. There are several excellent Dawn Chorus venues in Bear Valley Springs. The road from the Pinedale Nature Trail to Goat Springs (including Goat Springs). Also, the springs area of Devils Garden, and the North Fork of Sycamore Creek from the campground to Greenwater. Instead, lets walk the Paradise Valley road easement just below Mountain Park along Brite Creek.
At 7 AM, with a bang, our walk through the Dawn Chorus began with three neotropicals - the up-and-down of a tanager’s sing-song song, an oriole’s whistling and scolding, and a grosbeak’s unorganized warbling. From then on, for nearly three hours, we continuously heard (and saw) tanagers and grosbeaks – dozens and dozens of them. A prize – there atop a Valley Oak, a Green-tailed Towhee serenaded us over and over with his introductory single notes followed by high trills.
From below the road, redwings burbled and meadow larks sang. Proceeding up the canyon along the Brite Creek riparian corridor, the dee dee dee of chickadees, the multiple phrases of the titmouses, pee pee of the pewee’s, and the yank yank’s of white and red breasted nuthatches all contributed to the chorus. Fox and Chipping Sparrows, Spotted and California Towhees sang away. Four species of warblers, Lazuli Buntings and Purple Finches were all present and accounted for.
Fifty-one species in total, thirty-five of which were song birds, provided us with a fine Dawn Chorus. Even the sixteen non-songbirds helped out. Mallards and coots from the ponds, five Picids (woodpeckers and sapsuckers) drumming and chattering, while all morning long, valley and mountain quail called from the creek and mountain sides.
Soon after sunrise the warblers will switch from an aggressive dawn song to a daytime song. So what is this pronounced Dawn Chorus all about? Males singing early to be the first to attract unpaired females? Males demonstrating they are still on site to defend territory? A showcase for the female to choose the best quality mate? Dawn is favorable for long distance and quality sound transmission? All of the above are possible reasons for this explosion of song at dawn. Among ornithologists, it is not well understood.
Every morning, all day, in the evening, with every note and song the goal is for a successful mission. Mission? Success for a male requires a female, success for a female requires a male. Thus, each call and song note is for managing their day. That is, for territory, mates, negotiating, cajoling, persuading, impressing, contact - which is all part of the game of success. What is mission success? To perpetuate themselves - and for some reason this is accentuated at early light and results in the Dawn Chorus.
Good birding, gone birding.
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