Home & Garden Columns
This weekend, against my better judgment, I will be doing a couple of Audubon Society Christmas Bird Counts, one in Marin County, the other in Solano. (The Christmas Bird Count arose as a humane alternative to the traditional Christmas Side Hunt, whose object was to shoot every bird you saw. The data compiled by this annual exercise in citizen science has become a mother lode for ornithologists studying trends in North American bird populations.)
What I’ll find is hard to predict, birds being such mobile creatures. But if I’m out there in anything more clement than a blinding rainstorm, it’s a cinch that I’ll see ruby-crowned kinglets—probably lots of ruby-crowned kinglets, based on early scouting reports. This time of year they’re all over the California lowlands. I’ve seen them in the Lady Banks rose outside my kitchen window, in street trees, in an isolated patch of shrubbery at the El Cerrito Plaza shopping center.
Only male kinglets have the ruby crown, and you won’t see it unless the bird is in a heightened state of emotion. Normally it’s concealed under his greenish head feathers. When a male is confronting a territorial rival, though, or sometimes just feeling
testy, there’s a laser-like flash of scarlet.
Otherwise, this is not a showy bird: mostly greenish, with an off-white ring around the eye and two white bars on the folded wing.
It looks a whole lot like another small greenish songbird, the Hutton’s vireo. In the summer, when the kinglets are elsewhere that’s not a problem for birders. But in December I’ve seen both species foraging in the same tree.
There are various ways of telling them apart: kinglets are faster and twitchier, flick their wings more, have finer bills and a black bar behind the second white wing bar. If you get a really good look, the colors of the legs and feet are diagnostic. Hutton’s vireos have blue-gray legs; ruby-crowned kinglets have black legs and yellow feet. And if the bird says “che-dit,” it’s a kinglet.
The two aren’t closely related. Genetic studies place the vireos somewhere near the crows, and the kinglets with a huge complex of thrushes and warbler-like birds. Formerly considered part of the Old World warbler family, the five species of kinglets are now in their own family, the Regulidae. (The only other North American member, the golden-crowned kinglet, has a snazzy orange-black-and-white head pattern.) But some scientists think the ruby-crown is more like the Eurasian leaf warblers than the other kinglets. Taxonomy is a moving target.
We know ruby-crowned kinglets only as winter visitors. They nest in California, but not along the coast. As a breeding species, the ruby-crown is a mountain bird, ranging from the Siskiyous and Trinities down through the Sierra to the Transverse Ranges. That population appears to winter in Mexico; coastal-wintering birds come down from farther north.
That means we’re unlikely to be treated to the male kinglet’s vocal performance. I’ve only heard a ruby-crown sing once, on the Kaibab Plateau north of the Grand Canyon. It was a loud, exuberant performance and I had no idea what it was. It came as a considerable surprise when I tracked the sound through the trees and realized that the source was a kinglet. Arthur Cleveland Bent had it right: “The remarkable part of the song is the great volume of sound that issues from the tiny throat…, much greater than would seem possible from such a small bird.”
Sierran ruby-crowns usually nest about 4000 feet, sometimes as high as 10,000. They prefer semi-open conifer forests, sometimes forest edges. The typical nest is a deep cup suspended from an evergreen branch, well concealed among twigs. Construction materials in one nest included thistledown, aspen catkins, moss, lichen, grouse and mallard feathers, fibers from insect cocoons, and porcupine hairs. The clutch may be as large as twelve eggs, a high number for a small songbird. But unlike lowland-nesting birds, there’s no second brood—this is the parents’ only shot. Little is known about nest predation, although kinglets seem to be rarely victimized by parasitic cowbirds.
On both nesting and wintering grounds, kinglets specialize in gleaning insects from buds and foliage, favoring the outer tips of higher branches. The birds occasionally hover as they work their way through the trees. In addition to small insects and arachnids, kinglets may consume elderberries and poison oak berries. They’re frequent members of mixed winter foraging flocks, along with titmice, nuthatches, downy woodpeckers, and warblers, although they never function as flock leaders.
I will admit there have been times when I have gotten sick and tired of tallying ruby-crowned kinglets. I have in fact worked with a count partner who threatened not to record any more of them. Still, they’re lively little guys, good company in the wet winter woods whether you’re counting them or not. And there’s always the possible reward of that red flash.
Joe Eaton’s “Wild Neighbors” column appears every other Tuesday in the Berkeley Daily Planet, alternating with Ron Sullivan’s “Green Neighbors” column on East Bay trees.
Photograph by Ron Sullivan.
A ruby-crowned kinglet of undetermined gender.