1268 U.S. NATIONAL MUSEUM BULLETIN 23 7 part 3 



to the banding station in subsequent years. From the total of 1,361 

 birds banded at Stillwater between February 1948 and May 1960, 

 121 individuals returned one or more years for a total of 204 times 

 through May 1965. Of these 66 were banded as immatures, 50 as 

 adults, and 5 after April 25 when subadults could not be recognized. 

 The survival of these birds permits the construction of the following 

 table : 



These returns demonstrate a mean annual mortality from the first 

 through the seventh years of 45 percent. The species' potential life 

 span is thus slightly in excess of 10 years, but such advanced years 

 are probably not attained by more than one bird in each thousand 

 that survive the first year. Of my seven Return-6 birds, 4 were 

 banded as adults, and hence were at least almost 8 years old the last 

 spring they were taken, and could have been older. 



The files of the Bird-Banding Office at Patuxent, covering a period of 

 25 years and representing thousands of Harris' sparrow records, con- 

 tain only 13 Return-6 birds, including my 7. Of their three R-7 

 birds, the age at time of banding was not designated for two, but the 

 third and a fourth bird also banded in Oklahoma City by Victor Vacin 

 (correspondence) were immature when banded and therefore in their 

 8th year when last taken. The single R-S bird that W. Wilkins banded 

 as an immature in Chapman, Kans., Dec. 10, 1932, and recaptured 

 Feb. 13, 1941, holds the all-time longevity record to date of 8% years. 



Fall. — After completing their late summer molt, the hordes of 

 Harris' sparrows drift down from their northern home and swarm 

 across the prairie provinces by mid-September. Swenk and Stevens 

 (1929) point out: "A universal comment is that this sparrow is more 

 common in the fall migration than in the spring. This seems to be 

 connected with the fact that the fall movement is slower — requiring 

 three months to pass from its breeding grounds to the southern ex- 

 tremity of its wintering range- — the birds tarrying in attractive 

 localities or wandering somewhat to one side until urged on by colder 

 weather." 



The few direct recoveries of fall-banded birds give some idea of the 

 rate of the southward movement. One banded at Madison, Minn., 



