A practical guide to bird watching in Sonoma County, California

(Unless otherwise indicated, all phone numbers are in the 707 area code)


Very common in Sonoma County woodlands during the winter months. It's not unusual to see dozens in a couple of hours of walking in the woods. Usually arrives in late September and may stay as late as mid-May the following year, but most are gone by the end of April. Often solitary, but may be seen in loose mixed flocks with Oak Titmouse, Chestnut-backed Chickadee, nuthatches, warblers, and the like. Common also in urban parks and suburban settings with adequate vegetation. Gleans small insects in wooded environments and brushy undergrowth, foraging frenetically, never sitting still, often flicking its wings. Although Ruby-crowned Kinglets are common and rather unafraid of people--often coming within a few feet of observers--they are very difficult to photograph because they never sit still.


Prominent eyering, incomplete above the eye; a drab olive color above, pale below; two white wing bars, the lower one being the longer and more prominent; a sharply pointed, black bill; dark legs (although the feet are often yellowish); fine yellow-gold striping on folded wings and tail; ruby spot on the crown (usually hidden).

Often confused with Hutton's Vireo (Vireo huttoni). Hutton's Vireo is a little bigger and has a more elongated look. Ruby-crowned Kinglet is a rather plump little bird with a proportionately short tail that adds to the impression of compactness (although kinglets are very inquisitive and fairly fearless; when they stop to look at you from a few feet away, they often stretch their necks and turn their heads, which gives them a rather different, less pudgy shape). Hutton's Vireo has a small, sharp bill with a tiny hook on the end, but Ruby-crowned Kinglet has an even finer, sharper bill lacking the hook. Both birds have two white wing bars, but Ruby-crowned Kinglet has also a dark area beneath the lower wing bar, lacking in Hutton's Vireo. The darkest part of a Hutton’s Vireo’s wing will be between the wing bars. Also note the fine greenish-gold edgings on the folded wing and tail feathers in the kinglet. While the vireo may show similar edgings, they usually have a more distinct greenish-gold look in the kinglet, in my experience. Ruby-crowned Kinglet has a patch of red feathers on its crown (hence the name) that Hutton's Vireo lacks, but the kinglet rarely shows its crown, so lack of a visible red spot on top of the head by no means rules out Ruby-crowned Kinglet. If you see a flash of red, however, you can be sure your bird is the kinglet. The vireo's legs are heavier and paler in color than those of the kinglet, which has notably skinny, usually black legs (but see “Foot Color” below). Behaviorally, the kinglet is a much more nervous bird--constantly flitting from place to place, flicking its wings. Hutton's Vireo flits about looking for insects, too, but rather more deliberately than the kinglet (that said, the vireo may flick its wing as well, so that alone is not enough to separate the birds in the field). Vocalizations are quite different. Ruby-crowned Kinglet is frequently detected before it's sighted by its chattering, which is often said to sound like the clatter of an old-fashioned typewriter (links below).

Superficially resembles Pacific-slope Flycatcher (Empidonax difficilis) because of the similar eyering, but that bird is larger and has the typical alert, upright look of a flycatcher, has a pale orange lower mandible, and has a slightly crested look. It behaves very differently. It behaves like a typical flycatcher--perching, flying out to catch an insect, and then perching again, often in the same spot--rather than hopping around in trees foraging, although Ruby-crowned Kinglet will flycatch as well, but usually hovering near branch tips to pick off insects rather than repeatedly flying off a perch.   

Foot color: One thing I'm curious about is foot color. I've noticed that Ruby-crowned Kinglets generally have yellowish feet. Some have very yellow feet. In other birds, there's merely a suggestion of yellow, so the feet look brownish. The field guides often ignore this detail. Is it a purely random feature? Sibley shows the feet very yellow, without comment. The National Wildlife Federation guide illustrates a bird with somewhat yellow feet (using a photograph) and says the soles of the feet of the kinglet are yellow (although clearly some birds have entirely yellow feet). The 6th edition of the National Geographic guide shows a bird with yellow feet without comment, while the previous edition shows birds with black feet. The birds in the Peterson guides have black feet, although with a suggestion of yellow on the "shins."

Further reading:

Bolander and Parmeter, Birds of Sonoma County California, rev. ed., 2000, p. 95

Brinkley, National Wildlife Federation Field Guide to Birds of North America, 2007, p. 356

Dunn and Alderfer, eds., National Geographic Field Guide to the Birds of North America, 5th ed., 2006, pg. 346

Dunn and Alderfer, eds., National Geographic Field Guide to the Birds of North America, 6th ed., 2011, pg. 386

Dunne, Pete Dunne’s Essential Field Guide Companion, 2006, pp. 487-488

Ehrlich, Dobkin, and Wheye, The Birder's Handbook, paperback edition, 1988, p. 450

Fix and Bezener, Birds of Northern California, 2000, p. 294

Floyd, Smithsonian Field Guide to the Birds of North America, 2008, p. 349

Kaufman, Field Guide to Birds of North America, 2000, p. 294

Kaufman, Field Guide to Advanced Birding, 2011, pp. 95, 97, 348

Lukas, Bay Area Birds: From Sonoma County to Monterey Bay, 2012, pp. 187, 223

Parmeter and Wight, Birds of Sonoma County California, Update (2000-2010), 2012, p. 57

Peterson, Birds of Eastern and Central North America, 5th ed., 2002, pp. 242, 278

Peterson, Field Guide to Birds of Western North America, 4th ed., 2010, pg. 284

Peterson, Western Birds, 3rd ed., 1990,  pp. 268, 284

Sibley, Field Guide to Birds of Western North America,1st ed., 2003, pg. 336

Stokes, Stokes Field Guide to the Birds of North America, 1st ed., 2010, p. 541

Vuilleumier, American Museum of Natural History, Birds of North America: Western Region, 2011, p. 300

Voice: Cornell Lab of Ornithology: All About Birds--Ruby-crowned Kinglet

Voice: Cornell Lab of Ornithology: All About Birds--Hutton's Vireo



© Colin Talcroft, 2009, 2010, 2011, 2012, 2013

Unless noted, all photos by the author. If you would like to use one of my images, please ask for permission for non-commercial use with proper credit or commercial use with proper compensation.


For comparison: Hutton's Vireo: Place to Play Park

Santa Rosa, October 19, 2011. Note the heavier bill, longer tail

For comparison: Pacific-slope flycatcher. Note alert, upright posture; orange lower mandible, slightly crested look

This pair of photos illustrates why Hutton's Vireo and Ruby-crown Kinglet can be easy to confuse. The kinglet (on the right) is a little paler than usual--and less olive than a typical bird. From this angle--with the wings out of view and the length of the tail difficult to judge, it's hard to distinguish the two birds. Behavior and voice would provide the best clues having had only a glimpse (although the yellow feet are a give-away).   

A kinglet showing its ruby crown. Note the dark area below the longer white wing bar

and the green-gold striping on the folded wing and tail. Also note the strikingly yellow feet on this bird.

Spring Lake Park, Santa Rosa, December 18, 2011.

Ruby-crowned Kinglet, Spring Lake Park, Santa Rosa, January 21, 2012

Ruby-crowned Kinglet

Regulus calendula

1990-2013 Sonoma County data. Graph provided by eBird (www.ebird.org), generated August 4, 2013

EBird-reported occurrence in Sonoma County