Black-Headed Grosbeak Nesting at Fresno, California
Black-headed Grosbeak Nesting at Fresno, California.
Although the occurrence and nesting of the Black-headed Grosbeak (Hedymeles melanocephulus) has been noted by local observers at Fresno, California, in recent years, it is interesting to point out that Fresno was originally a semi-arid desert area unfavorable to this species. These grosbeaks usually are inhabitants of the more forested regions and wooded stream sides. Undoubtedly introduced cover and the trees in the parks of Fresno have attracted them. These fine areas of trees and moist lawns have also made possible the summer residence of the Western Robin.
The grosbeaks were first recorded by the writer on April 17, 1941, and by May 3 a nest had been constructed and a normal complement of three eggs was present. Approximately thirteen days later, the three purplish young had hatched; seven days after this the entire brood disappeared. This was the result of visits to the nest by the introduced western fox squirrels (Sciurus tiger rufiventer). These mammals, by reason of overabundance, present a problem for the nesting birds in the municipal Roeding Park area. In 1940, a grosbeak nest situated in the same tree as this year’s nest was destroyed in a similar manner.
To illustrate the ecological changes and resultant acquisition of nesting birds in recent years, it is to be noted that Tyler (Pac. Coast Avif. No. 9, 1913:87-88, 108) reported Western Robins in Fresno as winter and early spring migrants, the main band leaving in March, and Black-headed Grosbeaks were seen by him only in the spring as they loitered before passing on to more suitable summer homes. At the present time, both species are raising young in this region.
Richard H. Boyer
Fresno, California, June 16, 1941
