PUGET SOUND WHITE-CROWNED SPARROW 1345 



NuttalTs sparrows and those that breed at Friday Harbor, Wash. 

 Identity of these populations is not implied, although Ernest D 

 Clabaugh (1930) reports the capture in summer at Victoria, B.C., of 

 a Puget Sound sparrow he banded in Berkeley the previous winter. 



In addition to these variations, Puget Sound sparrows differ from 

 NuttalTs sparrows in the timing and duration of the phases of the 

 breeding cycle, in the average clutch size, and in the age when the 

 young become independent of their parents. The strongly migratory 

 populations of pugetensis nesting at the Canadian border compress 

 the active part of their reproductive cycle into less than two-thirds 

 the time consumed by the NuttalTs sparrows of central California. 

 In 1936 the Puget Sound sparrows at Friday Harbor paired, estab- 

 lished territories and fledged three broods in less than 4 months, 

 whereas from 1935 through 1938 the Berkeley NuttalTs sparrows 

 consumed from 6 to 6% months each year to achieve the same frac- 

 tion of the cycle. The compression is accomplished by the omission 

 of one and the shortening of three other more or less sharply delimited 

 phases. In pugetensis, territorial establishment requires about three 

 weeks and is not complete until the first day of incubation. In nut- 

 talli the same process is begun much earlier, and also requires about 

 three weeks, so that territory establishment is finished some six and 

 one-half to eight and one-half weeks before the first day of incubation. 

 The ensuing period of relatively settled conditions, when chasing and 

 fighting have either decreased or disappeared, does not occur in puge- 

 tensis. The three phases that are shortened are: the period of tem- 

 porary abeyance of song (14 days in pugetensis in contrast to 46 to 59 

 days in nuttalli, depending upon the year) the interval between com- 

 pletion of the first nest and laying of the first egg (an average of 2.6 

 days for seven records in pugetensis compared with 3.6 days for 12 

 records in nuttalli) and the interval between fledging of one brood 

 and laying of the first egg for the next (an average of 8.9 days for 

 five records of pugetensis in contrast to 20 days for six records in 

 nuttalli). 



Spring. — The same behavior elements as those described for nuttalli 

 appear in spring in pugetensis: increased force and frequency of sing- 

 ing, pursuits and fights, and trilling and posturing. Only the first 

 element is manifested on the wintering grounds. The others are 

 delayed, either until migration or more probably until arrival on the 

 breeding grounds. Then both sexes of Puget Sound sparrows regu- 

 larly engage in chasing and fighting and in trilling and posturing, 

 with much greater intensity than occurs in nuttalli. 



In late Feburary, about four weeks before migration, a few Puget 

 Sound sparrows begin to sing with greater vigor and more frequently 

 than in winter. From then on until late March and early April an 



