BAIRD'S SPARROW 761 



in best voice. At other times, his singing is spasmodic and he will 

 often lapse into a silence for an hour or more, unless disturbed. 



The female does not sing, but gives a high chip and sometimes a low, 

 crooning tr-r-i-p note when danger threatens her young. The male's 

 similar note is much deeper. The low, murmuring, Meeerr-meeerr 

 sound noted by Cartwright et al. (1937) is apparently an expression of 

 endearment. It may be uttered dui'ing copulation, though this has 

 never been proved. Both parents utter it when approaching the 

 nest after the young begin to call for food on their sixth day of life. 

 The nestlings soon give voice to a stronger tip note, and when one was 

 lifted from the nest on the eighth day of hfe, it gave a loud, squalling 

 cry. The species has the usual chipping flock call in migration. 



I have noted earlier that familiarity with the song of the Baird's 

 sparrow is the best means of locatmg the bird in the field. Two 

 recently issued song recordings, "Finches," by Donald J. Borror and 

 William W. H. Gunn (1960), and "Frame Spring," by W. W. H. 

 Gunn (1962), include excellent reproductions of the variable melodies 

 of the species. Such recording's will prove of great aid to all who wish 

 to become acquainted with this lovely little finch. 



Field marks. — A. bairdii strongly resembles A. savannarum and 

 other closely allied genera. Allan R. Phillips tells nie by letter that: 

 "In Mexico I once chased a remarkably pale, buffy sparrow for a long 

 time, in September, sure that it was a Leconte's, Baird's, or some other 

 rarity. I finally got it, and it proved to be just a washed-out, frealdsh 

 Savannah!" 



In my experience, the ocherish patches on Baird's sparrow's head and 

 neck are not apparent, even through good glasses, unless the bird is 

 at close range. At greater distances a back view shows a slim, dark 

 bird, and when it turns to face the observer, the shining, grey front 

 resembles that of a pale Savannah sparrow, which as a general rule 

 looks much darker. 



Like the grasshopper sparrow, the other member of the genus, 

 Baird's sparrow has a flat-headed silhouette which aids in identifica- 

 tion. The low, hurried flight across the grass and sudden pitch to 

 earth is another good mark, though not an infallible one. 



Since the sitting hen is invariably flushed from the nest at very 

 close range, it is often possible to note the pale-yeUow margin on the 

 two outer tail feathers. 



Enemies. — Among the dangers confronting the prairie-dwelling 

 species of birds, fire and the plow are the most serious, and the efTects 

 of the plow are even more profound and lasting than those of an all- 

 consuming fire. Land eventually recovers from a scourge of flame, 

 but that once turned by the plow is usually lost forever to ground- 

 nesting birds. 



