The Golden-crowned Sparrow is one of the two most familiar sparrows in the park, the other being the more numerous White-crowned. Despite its regular winter appearances in California, scientists know very little about its life during the warmer seasons, when it migrates to the far north. The Cornell bird lab website says, “Though it’s familiar to many during winter, Golden-crowned Sparrows vanish for the summer into tundra and shrublands from British Columbia to Alaska, where little is known of its breeding habits…. This sparrow is one of the least known of our songbirds, particularly on its northern breeding grounds. It has been the subject of only a few laboratory and field studies, so most of what we know about it comes from scattered notes in scientific journals.”
During its winter visit, this sparrow mostly feeds on vegetable matter, chiefly seeds. It plays an important role in suppressing weed growth. The Wikipedia writer notes, “The species is an important destroyer of weed seeds on the Pacific Slope, with various ryegrasses, fescues, bromes, pigweeds, chickweeds, mulleins, filarees, common knotweed and poison oak among its known food sources.” That makes this bird a most welcome guest in the DAWN area, where I filmed it. Native plants established by the nonprofit DAWN workers in the mid-1980s have been struggling ever since for sun and soil against exotic weeds. Human volunteers can at best pull some of the worst weeds after they’ve grown tall. Only a bird can perform the precision prophylactic surgery that keeps them from growing in the first place.
Golden-crowned Sparrows, as the Wikipedia writer also noted, commonly feed with their mates; the females lead and the males follow. There was a second bird with this one when I filmed, but the other kept to the shadows and I could not get a satisfactory image.
Note in the first few seconds of the video how the bird raises the feathers on top of its head almost into a crewcut. The iconic yellow swab of the paintbrush on its crown is still subdued on this bird. It’s probably a youngster or a teenager. As it matures, the “gold” on its crown will grow brighter, deeper, and more sharply defined. It will serve as a chief marker of the bird’s attractiveness as a mate and its rank among other males of its species.