NUTTALL'S WHITE-CROWNED SPARROW 1319 



breeding time. On rare occasions I even found two birds perched 

 conspicuously, alternating in loud singing. Although females do not 

 usually show signs of territorial jealousy, I have one case of a banded 

 adult female which not only sang forcefully but engaged in a dispute 

 with another adult. The immediate cause seemed to be the desire of 

 both birds to feed on the same pyracantha berries. 



During early September female III had frequented a certain bush on the edge 

 of her territory until, we may imagine, habit verged upon necessity and the spot 

 was unseasonably invested with the power to stimulate possessive jealousy. On 

 September 9 and 15 I saw her sing there several times. Her song was complete 

 but weaker than that of her mate. On the morning of September 17 1 found her 

 there on the ground, singing as forcefully as any male in breeding time. Then 

 an unbanded adult in the same patch of shrubbery sang, somewhat less vigorously. 

 This was male VIII, the neighbor on the east. They sang at one another for 

 four or five minutes, shifting over the ground about six feet apart. Then the 

 male chased female III around the edge of the shrubbery. She lit on the ground 

 and both sang again. Another chase took place, then more singing. The next 

 morning this was all repeated, but female III sang less forcefully. The same 

 afternoon I found both feeding silently on the same berries two feet apart, and 

 so for the next four mornings. Both sang occasionally, but I saw no more pursuits. 



Territorial and sexual displays by adults in the fall are known for 

 many species of birds (Marshall 1952). 



"Pursuit is common among immatures in fall and winter. It is 

 usually momentary, involving flock mates which may resume peaceful 

 foraging a minute or so later. Sometimes, however, pursuit has been 

 accompanied by loud singing and fighting, suggestive of a territorial 

 dispute." 



The data cited point to "* * * a more or less passive limitation 

 of pairs to their breeding areas in winter, with almost complete 

 tolerance of sojourning strangers and only rare flare-ups of jealousy 

 between established neighbors. Restriction in winter is obviously 

 not the product of conflicts between neighboring pairs; chasing, fight- 

 ing, and patrol are almost completely absent. The attitude of the 

 male toward immature and mateless birds gives us little reason to 

 suppose that he would resent invasions of adjoining pairs if such 

 occurred." 



Banding. — White-crowned sparrows live close to man, trap easily, 

 and forage and perch with the lower part of the leg exposed so that 

 color bands are plainly visible. Many banded birds re-enter the 

 same traps again and again. Each year thousands of white-crowned 

 sparrows are banded, and hundreds previously banded are recaptured. 

 In the April issue of the "Western Bird-Bander," the Western Bird- 

 Banding Association publishes annually the numbers of birds reported 

 banded by its members in western North America. In 1959, 6,61G 

 white-crowned sparrows were banded. This is 5.9 percent of all 

 birds reported banded that year, and is the largest total for any 



