SAN FRANCISCO BROWN TOWHEE 615 



to take towhees, and only two were found in 285 identified prey 

 items. Fitch et al. (1946a), in their study of the red-tailed hawk 

 report only 3 towhees in 625 articles of food brought to the nest, and 

 7 towhees in 2,094 pellets. Fitch et al. (1946b) found only 1 towhee 

 in 41 items at two nests of the Cooper hawk. Apparently the pre- 

 dation rate on towhees in this area is low and has httle effect on the 

 population. 



J. M. Linsdale (1931), investigating the destructive effects on 

 wildlife of a rodenticide then in common use, found only one towhee 

 killed by this material. Compound 1080, now widely used for rodent 

 control, particularly ground squirrels, is mixed with oats and colored 

 a bright canary yellow that apparently make the seeds unattractive 

 to birds. 



Towhees evince a mobbing reaction to owls during the mating 

 season, but not a very intense one, according to S. A. Altmann (1956), 

 and Fitch found no towhees among the owl foods he identified. 



Young brown towhees in the nest are occasionally parasitized by 

 fly (Protocalliphora) larvae. O. E. Plath (1919) examined eight 

 nests and found two of them heavily infested with 53 larvae per nest. 

 None were observed in the Berkeley population. C. M. Herman 

 et al. (1942) found five out of eight towhees infected with Isopora. 

 Hippoboscid or flat flies are found on towhees during the warm 

 months. 



Because of their Uking for roadside vegetation and their poor 

 powers of flight, brown towhees are frequent victims of automobiles. 

 J. McB. Robertson (1930) listed four such casualties in a study in 

 southern California. 



Distribution 



Range. — The San FrancLsco brown towhee is resident in California 

 in the humid north central coastal region from Humboldt County 

 (Korbel) to Santa Cruz County (Corralitos) , and inland to the western 

 edge of the northern San Joaquin Valley. 



Egg dates. — California: 8 records. May 9 to June 28. 



PIPILO FUSCUS CRISSALIS (Vigors) 



California Bro^vn Towhee 



PLATES 34 AND 35 



Contributed by Henry E. Childs, Jr. 



Habits 



Most of our information about this south central coastal race 

 comes from the Hastings Natural History Reservation in the northern 



