1534 U.S. NATIONAL MUSEUM BULLETIN 237 part 3 



The Alaskan Song Sparrows have become rather specialized birds, adhering very 

 closely to the sea beaches throughout most of their range, and only in the south- 

 eastern district from Yakutat Bay south do they show any resemblance to the 

 habits so familiar to bird students elsewhere. * * * The species has one of the 

 most curious ranges of any in Alaska. It is found along a narrow coastal strip 

 from Dixon Entrance [at the boundary of Alaska and British Columbia] to Attu 

 [the outermost Aleutian] * * * and only as straggling individuals in the Bristol 

 Bay area, on the Pribilofs, or on the north side of the Alaska Peninsula. 



It is also one of the most variable of Alaskan birds. The races of southeastern 

 Alaska are dark and relatively small * * *. Northward and westward from 

 Yakutat, however, the birds become larger and paler, reaching the grayest race in 

 the Alaska Peninsula and in the easternmost of the Aleutian Islands [sanaka], 

 and then becoming browner but not much darker in the western Aleutians [maxima]. 



Ridgway's measurements of the length, although taken from dried skins, give 

 some indication of the variation in the size of these birds as one passes to the west. 

 Males of the southeastern race (rufina) average 159 mm. in length while those of 

 the Aleutian Islands (maxima) average 187 mm. * * * These big birds * * * 

 with the normal markings greatly obscured and softened look entirely unlike their 

 more sharply marked relatives to the east; and yet, they sing about the same song. 

 It is an unusual experience for an ornithologist to watch one of these comparatively 

 gigantic Song Sparrows behave exactly as do their small counterparts far to the 

 south. 



Spring. — Those individuals of the two migrant races that have 

 wintered in southeast Alaska, British Columbia, and the Pacific states 

 of the United States probably return to the breeding range in March 

 and April. Thus caurina is found in California until March, and 

 Swarth (1911) took specimens of that race in the Alexander Archi- 

 pelago just south of the breeding range in middle and late April. 

 Gabrielson and Lincoln (1951) mention a specimen of kenaiensis 

 collected in southeastern Alaska outside the breeding range on Feb. 6. 



The spring behavior of the resident races may perhaps be typified 

 by that of maxima on Attu, as described by Sutton and Wilson (1946) 

 for the period Feb. 20 to March 18. "As a ride we saw the birds in 

 twos, and we believe that most of these were actually mated pairs. 

 They were not in breeding condition, however (the gonads of specimens 

 examined being unenlarged), and we saw little in the way of court- 

 ship, few pursuit flights of any sort, and no copulation. Singing we 

 heard now and then on windy days, but it was especially noticeable in 

 calm, sunny weather." 



Nesting. — Richard F. Johnston (1954), from a study principally of 

 egg collections, fixes the duration of nesting in the Alaskan Peninsula 

 and the Aleutians (presumably, sanaka and maxima, and possibly 

 kenaiensis, insignis, and amaka) at about 7 weeks and indicates that 

 breeding in Alaska begins on about May 15, reaches a peak on about 

 June 10, and ends about July 5. 



