SAN FRANCISCO BROWN TOWHEE 607 



Alnus and Salix and in tangles of Rubus vitifolius, R. parviflora, and Ribes. 

 Plants such as Baccharis, Diplacus, Vilis, and Sambucus may also be utilized. A 

 few specimens have been taken in Artemisia. Disturbed areas may be used when 

 the proper growth form has succeeded the original vegetation or when the original 

 vegetation has been modified to provide suitable habitat for the brown towhees. 

 Grazing, farming, logging operations, road building, and landscaping have 

 opened areas to invasion by towhees. Local spread or increase in numbers has 

 resulted. 



Two Californian races occur mainlj' or entirely in associations other than chap- 

 arral. P. f. peiulans of the humid north-central coast occupies an area in which 

 chaparral is much restricted. This race is found in chaparral where this plant 

 formation occurs within its range, but the birds have been restricted for the most 

 part to the secondary association just listed. P. f. eremophilis of the Argus 

 Mountains of Inyo and San Bernardino counties is found in rocky canyons that 

 support extensive thickets of Salix. 



Within these plant associations the brown towhee is an inhabitant 

 of the brush edges. It is found along roads, trails, clearings, on 

 lawns, wherever it can forage in the open with a clear view of pred- 

 ators and close to safe cover. Edge also appears to be of importance 

 in determining territorial size. 



During the winter towhees are found in association with other 

 species of ground-feeding birds, particularly the white and golden- 

 crowned sparrows, song sparrow, and house finch. It is the despot 

 wherever it is found, putting all smaller birds to flight by strongly 

 attacking those in its path. At Berkeley only the larger Steller and 

 scrub jays dominate any chance encounter. 



That the brown towhee is a conspicuous bird in its habitat is 

 indicated by T. L. Rodgers and C. G. Sibley (1940), who recorded it 

 in 99.6 percent of trips taken on the Berkeley campus throughout 

 the year. 



Territory. — Although lacking in brilliance of plumage and beauty 

 of song, the brown towhee is well able to establish and maintain a 

 typical passerine territory providing all the necessities for its compara- 

 tively sedentary life. In it are found mating and nest sites, food 

 gathering areas, and escape areas for flight and roosting. A strictly 

 resident bird, the male towhee defends his territory vigorously from 

 all encroachment by others of his species. 



Territorial defense is first noted in late fall after a period follo-wnng 

 the major dispersal of juveniles. Chasing and fighting between 

 individuals becomes more frequent and pronounced in spring with 

 the onset of breeding. Normally a relatively quiet bird, the towhee 

 then becomes a loud, dominating tyrant to the hapless neighbor or 

 vagrant towhee caught trespassing on his territory. 



Song plays only a small part in the announcement of territory. 

 Birds of neighboring pairs can see one another over most of their 

 territories and trespass is usually observed and reacted to almost 



646-7.'?7 — GS— pt. 2 2 



