SAGE THRASHER 433 



notes wander on, to change and become more intricate, burring calls, 

 that while harsh are not unmusical, creep in as an accompaniment to 

 clearer whistled notes that are varied and pleasing. Low trills and 

 changing combinations mark the song, reminding one of the im- 

 provisation of some gifted musician who, playing apparently at ran- 

 dom, brings forth tones that follow one another in perfect harmony." 



Ralph Hoffmann (1927) says: "Its song, given from the top of the 

 sage or from a fence post along the road, is a long succession of warbling 

 phrases with very little range of pitch and with constant repetition 

 of one accented note. The bird's alarm note is a chuch^ chuck suggest- 

 ing a blackbird, and a sweet high toheurr.''^ 



Field marks. — Though there is a fancied, superficial resemblance 

 to the mockingbird in behavior, the illusion is soon dispelled when 

 the bird takes to the air, for the conspicuous white areas in the wings 

 of the mocker are lacking in the thrasher. The sage thrasher can be 

 recognized as a plain brownish gray bird above, with a darker tail 

 tipped with white on the outer feathers, with a short, straight bill, 

 and with a breast distinctly streaked with black. None of the other 

 thrashers need be confused with it. 



Fall. — The sage thrasher is a decidedly migratory species, retiring 

 in fall from nearly all its breeding range and spending the winter 

 near or beyond the southern boundary of the United States. Its mi- 

 gration is well marked and its numbers are sometimes impressive. 

 Harry S. Swarth (1924) gives a good illustration of this, as observed 

 in Arizona. The birds were "first seen September 11 ; a few days later 

 this became the most abundant bird species in the piiion- juniper belt. 

 The Sage Thrashers were obviously migrating, and some days all the 

 birds seen would be rapidly moving southward, an advancing army 

 really impressive in numbers. Scores were in sight at once on the 

 ground, running from bush to bush, others were taking short flights 

 through the trees, and still others were in scattered companies over- 

 head, almost like flocks of bluebirds in flight. The usual call-note 

 is a harsh chwck^ suggestive of that of a blackbird, but some thrash- 

 ers were heard giving fragments of their striking song from perches 

 in the junipers. 



"By the middle of October the number of Sage Thrashers had 

 markedly diminished. On the 20th none were seen, but on the 23d 

 two appeared, the last observed." 



DISTRIBUTION 



Range. — Central southern British Columbia to northern Mexico. 



Breeding range. — The sage thrasher breeds north to central south- 

 ern British Columbia (Keremeos, Similkameen Valley, and the Okana- 

 gan Valley as far north as Okanagan Landing) ; central Idaho (June- 



