Nesting of the Black-Chinned Hummingbird in Santa Clara County, California
Nesting of the Black-chinned Hummingbird in Santa Clara County, California
There appear to be but three records for the Black-chinned Hummingbird (Archilochus alexandri) for the Bay counties of west-central California (Grinnell and Wythe, Pacific Coast Avifauna No. 18,1927, p. 94) and no record at all of its nesting in that region. Some twenty years ago the writer gave about one hundred sets of locally taken eggs to a young friend. After being packed away for nearly that length of time they were recently returned. Among them were three sets with nests of the Blackchinned Hummingbird. One set was still in perfect condition but unfortunately the other two were broken.
Set number 1 was taken on May 5, 1907. The nest was placed eight feet up on the end of a sycamore limb and contained two fresh eggs. Nest number 2 was taken on May 12, 1907, and was placed about fifteen feet up in a small white oak; two fresh eggs. Nest number 3 was taken May 14, 1907, and was only two feet up on the tip of a low-hanging sycamore limb. It held two fresh eggs. These sets were taken by the writer about four miles west of Gilroy.
The nests are all typical of this species and are composed entirely of down taken from the underside of sycamore leaves, and cobwebs. One pair of birds was under close observation during nest building and the female apparently gleaned most of the material from dried leaves which were frozen earlier in the spring. It would be interesting to know if this bird ever uses any other down in the construction of these spongelike nests. This may not be the northern breeding limit of this bird along our coast. A search should be made along the sycamore-bordered streams of northern Santa Clara and Alameda counties. Male birds were noted July 15, 1926, and April 1, 1928, at the writer's home, feeding among potted plants on the porch.
W. E. Unglish
Gilroy, California, May 16, 1932
