COMMON REDPOLL 409 



believed the birds had been swept up to the higher parts of the 

 mountain by the strong southwest storms which hit the peak at that 

 time of year. 



Courtship. — At Indian House Lake during 1945 the common 

 redpoll began to sing on March 5, about a week after its more northern 

 relative, the hoary redpoll (C. h. exilipes), which wintered there with 

 it but did not summer. From March 12 to the end of the month 

 the birds were very noisy and excited. By the last week of March 

 many appeared paired and sneaked through the alder thickets near 

 our camp, calling plaintively and behaving shyly. By mid-April 

 scattered pairs had apparently selected nesting sites, but they were 

 so extremely secretive I found it impossible to fix the status of the 

 few pairs that wandered about near us. Some days the thickets 

 along the lake seemed deserted, when suddenly a passing northern 

 shrike would draw up a swirling group of 10 or so redpolls, seemingly 

 from nowhere. Once the threat passed these sprites melted back 

 into thickets so unobtrusively that their momentary clatter seemed 

 to have been an error of observation. 



Not until the morning of May 25, 1945, did I fkst observe mating. 

 Although coitus did not actually take place, the female crouched, 

 dropped her wings, and twittered excitedly. The male stood before 

 her stiffly and bowed a few times. That afternoon, and again on 

 May 30, bu'ds were seen picking up ptarmigan feathers from our camp 

 hillside, evidently for nest material. 



No truly territorial behavior has been reported by the few naturalists 

 who have witnessed this redpoll's prenuptial activities. Song is 

 most active before the flocks break up, and no fighting over nesting 

 territories appears to take place. The irregular spacing of nests, 

 sometimes close together, seems to confu-m this view. 



William Dilger's studies of captive redpolls offer new enlighten- 

 ment on this score (Dilger, 1957). He found that a rigid social 

 hierarchy exists within the flock, the males being clearly dominant 

 over females during the nonreproductive season. This dominance is 

 linear, from high to low male, and from low male to high female 

 to low female. The low male usually directs his attacks toward a 

 female after losing an encounter with a male. Most significant, 

 however, is the fact that females become aggressive and dominant 

 over the males as the breeding season approaches. European studies 

 suggest that this reversal of dominance is characteristic of cardueline 

 finches in general. "Each female," Dilger states, "clearly singles 

 out a certain male to which she behaves in a particularly aggressive 

 manner. These are the couples between which pair bonds are 

 ultimately formed." Once the pair bond is fully formed, the males 



