Orange-crowned Warbler

Our most common warbler next to Yellow-rumped Warbler (Setophaga coronata) and probably the most drab, although an Orange-crowned Warbler in fresh plumage may be quite pretty. Present year-round in Sonoma County, but uncommon during the winter months. Mostly seen during spring and autumn migration and somewhat less frequently in the summer. Spring migrants generally begin arriving in early March but birds may show up as early as late February. Typically seen in open woodland, along forest edges, and in scrubby areas both at the coast and inland. Prefers oaks and other broadleaf trees with dense vegetation nearby. Seems to especially like willows and alders. Often near water. Diet is mostly insects (particularly oak moth caterpillars in the spring, according to Lukas), but will eat fruit sometimes and occasionally drink nectar. Known to drink from sapsucker wells.

Three main subspecies are recognized. They are Oreothlypis celata lutescens, O. c. celata, and O. c. orestra. Our breeding population is O. c. lutescens, which is mostly a dull, greyish green. The other two subspecies are characterized by greyer heads. We mostly see O. c. lutescens, but O. c. celata and orestra may be present. (A fourth subspecies is confined to the Channel Islands off the southern California coast.) Lutescens breeds along the Pacific Coast, from northern British Columbia to central California.

Orange-crowned Warbler is poorly named. The orange crown is nearly always hidden. Count yourself lucky if you ever see it. The bird in the photograph above (Diekmann’s Store, Bodega Bay, January 18, 2015) is showing the crown more than any I’ve ever seen, but even this is subtle and easily missed (note that this bird has some kind of resin on its face, creating an atypical black patch at the base of the bill). Orange-crowned Warbler is, in fact, notable mostly for its lack of notable field marks. Overall dull olive, but color is variable. Some birds are more yellow, others more grey. Lacks wingbars. Longish, dark tail. Yellowish undertail coverts in all plumages. Often faint, diffuse streaking on breast and flanks (may not be obvious in the field). Usually shows faint, pale supercilium (eyebrow), a faint but distinct dark eyeline, and a faint, split eyering. Bill is notably pointed and slender. A very lean, muscular, athletic little bird that forages actively and may be quite acrobatic. Does not bob or wag its tail.

In our area, most commonly confused with Yellow Warbler (Setophaga petechia), but that bird will have a proportionately larger eye; a fine, but complete, yellow eyering; a plumper (although elegant) shape; a stouter bill; and an all-yellow tail. Similar, but uncommon species we sometimes see in the county include Tennessee Warbler (Oreothlypis peregrina), and Nashville Warbler (Oreothlypis ruthicapilla). Tennessee typically has a brighter green back, a more conspicuous supercilium and will have white rather than yellow undertail coverts, along with a shorter, paler tail. Nashville shows much stronger contrast overall (grey-green above, yellow below), has a more distinct, complete eyering, and looks much more clearly hooded than the grey-headed subspecies of Orange-crowned Warbler. First-year female Common Yellowthroat (Geothlypis trichas) may also be similar, but that bird will have a notably pale (although not always yellow) throat that contrasts with the rest of the underparts. Yellowthroat is much more likely to be close to water and unlikely in wooded settings. Vocalizations of these various warblers are quite different (links below).

Vocalizations are worth studying. A trilling Orange-crowned Warbler is often one of our first harbingers of spring. The trill is musical, rising a little in pitch and then dropping in pitch at the end in a distinctive way. May be confused with other birds that trill in the spring, including Spotted Towhee (shorter, straighter, and lower pitched) and Dark-eyed Junco (longer, straighter, slightly lower pitched). See links to recordings below. Stephenson and Whittle’s The Warbler Guide has excellent (if challenging to understand) information on vocalizations using sonograms.

Older sources will put this bird in the genus Vermivora as Vermivora celata.

English synonyms: Dusky Warbler, Lutescent Warbler (neither commonly used in Sonoma County)

Orange-crowned Warbler in other languages--German: Orangefleck-Waldsänger; Spanish: Chipe Celato, Chipe Corona-anaranjada, Chipe Corona-naranja, Chipe Deslustrado, Reinita Coroninaranja, Reinita Olivada, Chipe Corona Naranja, Chipe Corona Anaranjada, Chipe Corona-naranja; French: Fauvette verdâtre, Paruline à couronne orange, Paruline verdâtre; Russian: Рыжешапочная древесница, Japanese: サメズアカアメリカムシクイ (Samezuaka amerika mushikui); Chinese: 橙冠虫森莺

(Language information from Avibase, Birds of Europe (Mullarney et al, Princeton Field Guide Series), and Birds of Asia (Mark Brazil, Princeton Field Guide Series).