PUGET SOUND WHITE-CROWNED SPARROW 1347 



the pairs settled down to a routine identical with that of Nuttall's 

 sparrow. 



The behavior, then, of pugetensis in spring differs from that of 

 nuttalli, in the interpolation of a migratory flight between the begin- 

 ning and the end of the transition from flocking to paired isolation, 

 in the time the three behavior elements appear relative to the start 

 of breeding, and in the intensity with which they are manifested. 

 The relative disorder among the migrants during the "shake-down" 

 period is not unnatural and may represent merely the result of cir- 

 cumstances rather than an intrinsic variation in habit or temperament. 

 The migrants must establish themselves on ground unseen for seven 

 months and perhaps wholly unfamiliar to some of the adult birds. 

 The first-year birds must seek and seize at once what the young 

 Nuttalls drift into or seek at leisure. The sudden change from a 

 gregarious to an isolated habit perhaps creates a deeper psychological 

 disturbance and contributes to the violence of the process of spatial 

 arrangement. 



Courtship. — The Puget Sound sparrows arrived at Friday Harbor 

 apparently already paired. On Apr. 12, 1936, two days after the 

 main influx, I saw a female trill and posture. From this time on, 

 both actions increased in force and frequency until April 21, when I 

 first saw a pair copulate. By April 27 trilling and posturing ceased 

 temporarily, to be resumed prior to the start of the second brood. 



We have evidence that, as in nuttalli, the members of a breeding 

 pair of Puget Sound sparrows may remate the following season. 

 Mrs. Forrest Fuller (pers. comm.) observed the same color-banded 

 pair nesting in the same hedge in her garden in 1936 and 1937. 



Nesting. — At Friday Harbor in 1936, the females started to build 

 the nest one or two weeks after their arrival. Behavior during nest- 

 building and the time it took to finish the nest were the same as in 

 the Nuttall's sparrow, but the interval between fledging the first 

 brood and starting work on the second nest was shorter than in 

 nuttalli. Six Puget Sound sparrow females that I followed started 

 work on their second nests only two to four days after the first brood 

 was fledged. 



The female alternates between feeding her young and building the 

 new nest. That this may result in confusion is illustrated by the 

 behavior of one female I observed on the morning of May 28 (Blan- 

 chard, 1941): 



* * * I saw her disappear with material into the hedge a few feet to one side 

 of the first nest site. There I subsequently found a new nest with the walls 

 partly formed. * * * Between half-past eight and half-past nine she made 

 seven trips to the hedge to feed the fledglings, then stayed away for half an hour. 

 She returned at ten, carrying straws in her beak, flew to the abandoned nest, 



