Jon Dunn/FIELD NOTES

The Identification of Immature Orioles

The Western Tanager Dec. 1975

First-Year-Females-Orioles-illustration-james-davis

First Year Females (Orioles), Illustration by James A. Davis

During the winter months, the flowering eucalyptus trees and other flowering trees and shrubs support a small number of wintering orioles. In addition, feeders with sugar water are also excellent attractors of wintering orioles and tanagers. Surprisingly, the variety of orioles is quite diverse, and on the coastal slope the eastern types are as numerous as our common nesting species, the Northern and the Hooded. Therefore, all orioles that one encounters should be carefully scrutinized. Since the overwhelming majority of wintering orioles are immatures, I feel that a review of their plumage characteristics and call notes would be useful. The marks that I will discuss will apply both to females and first year males, though the young males are generally brighter.

The most common wintering oriole is the Northern (Bullock's and Baltimore). Although the two have been lumped, it is still useful for the observer to delineate the particular race encountered, in order to get a fuller understanding of their relative distribution. The Bullock's type is only slightly more likely than the Baltimore. The female Bullock's can be recognized by its grayish-green superciliary and a whitish belly. It also has a pale yellowish green breast. The female Baltimore, on the other hand, has olive-brown upperparts (including the tail), and the color of the underparts is a fairly bright orange on the throat, breast, and undertail coverts. The color of the belly is always paler, shading from a buff to sometimes even a dark gray. Therefore, the fact that a female or young male Northern Oriole has a gray belly does not automatically indicate that it is a Bullock's. The Baltimore lacks the superciliary of the preceding race, and the white wingbars seem to contrast more with the rest of the wing. Young males are similar to the females, though invariably brighter.

Our other nesting species, the Hooded is a very rare bird in the winter; I have seen it only once. The Hooded can be easily recognized from the Northern by its yellowish-green belly. It doesn't seem to be as plump a bird as the Northern, appearing slightly longer tailed; and the bill is not nearly as straight. The call note, a whistled "wheet," is unlike that of any other North American oriole. The chatter is similar to the Northern, but it seems to be less guttural.

Slightly more numerous than the Hooded is the Orchard Oriole. Contrary to the indications in the field guides, the female Orchard is a very easy bird to identify. To start with, it is much smaller than a Hooded, being hardly larger than a House Finch. The bill of the Orchard is much smaller than that of the preceding species, and it appears more sharply decurved. The underparts of the Orchard are of a clearer, more intense yellow, lacking the greenish tones of the Hooded. This oriole also has the unique habit of flicking its tail to the side. This is a characteristic that I have not observed in any other species of oriole. Finally, the call note, a sharp "chuck," is very unlike that of the Hooded. The Orchard can be immediately told from the Northern Oriole by its much smaller size and its yellow belly.

The Scott's Oriole is the rarest wintering oriole that I will discuss. Essentially, the species resembles a Hooded, except that the coloration is of a much darker grayish-green hue, lacking the yellow tones of the preceding two species. Most female Scott's also show some black flecking on the throat. The belly is often almost a dull gray, and, unlike the other four orioles, the back of a Scott's is narrowly marked with vertical blackish or dusky streaks. The bill of the Scott's is quite long and slightly decurved. The call note, a harsh "shack" (sometimes given in a series), is quite unlike that of the Hooded.

The marks that I've discussed apply only to females and first year males. By the spring, the young males have changed to a plumage intermediate between that of the adult and the 1st year male. Some, like the Hooded and Orchard, change only slightly (picking up black on the throat), while the other species go through a more extensive change of plumage.

Originally Published in Western Tanager, Vol. 42 No. 4, December 1975

Transcribed, July 2013 for "Articles from the Archives" www.laaudubon.org, Los Angeles Audubon

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