1518 U.S. NATIONAL MUSEUM BULLETIN 23 7 part 3 



brown markings (auburn in color) predominating over any other 

 shade on the dorsal surface. 



Behavior. — Female song sparrows arose about 5 minutes after civil 

 twilight in clear weather and 7 minutes after civil twilight in cloudy- 

 weather. Males did likewise in January and early and late fall; but in 

 early spring they arose at civil twilight, and later in spring and in 

 mid-fall when in full song they rose 4 minutes before civil twilight. 

 Roosting took place at about 10 times the light values of the rising 

 time of the female. From December through May and again in 

 October the last notes of the males came with surprising regularity 

 13-14 minutes after sunset in clear weather. 



Song sparrows use several methods for defense of nest and young. 

 They may sometimes threaten an enemy with posture and sound. 

 They attack cowbirds that approach the nest site. Some individuals 

 attack small snakes, while others ignore them. Typically solicitude for 

 the nest reaches its peak when the young are ready to leave it. 

 Warning notes from the parents at the approach of an intruder induce 

 silence in the young. Distraction display, in which the bird runs 

 about close to the observer with wings held stiffly erect and tail 

 depressed, was typically shown when young of 6 or 7 days shrieked 

 when being banded. Occasionally parents will try to lure young to 

 safety by bringing food near, then hurrying away with it. 



Experiments with enemy recognition, as well as observations in 

 nature, led to the conclusion that owls are recognized by song sparrows 

 largely through an inborn pattern, hawks through their rapid move- 

 ments, and cats and cowbirds through conditioning. With a hand- 

 raised bird, memory of circumstances connected with strong alarm 

 persisted after 4 to 19 months, a response that has definite biological 

 value (Nice and ter Pelkwyk, 1941). 



Anting was observed in 3 of the hand-raised song sparrows; both ants 

 and sumach berries were used. Anting first appeared at the age of 

 36 to 37 days (Nice and ter Pelkwyk, 1940). 



Although the song sparrow is only slightly gregarious, it shows the 

 basic mechanisms for social integration (Nice, 1943.) 



Voice. — Eight different kinds of vocalizations were heard from young 

 song sparrows, 16 from adult males, and 15 from females. Songs are 

 given at the rate of 5 to 7 a minute when the bird is singing steadily, 

 but occasionally during encounters involving territory establishment, 

 the rate may be 10 times a minute. Sometimes a primitive-sounding, 

 irregular flight song is uttered. Young birds change often from one 

 song to another; at the height of vigor there is sustained effort and 

 one song may be sung 60 or even 70 times in succession; an old bird 

 may change from one song to another somewhat more often. The 



