Orioles are among the most beloved American birds. The bright and patterned color of adult males is relatively easy to tell apart. But there are as many female and immature birds of both species that visit bird feeders or are seen in the field. Of course, we want to know what oriole is visiting our feeders or we see in the field.
This article details the appearance and natural history of adult males, females, and immature orioles.
Baltimore Oriole (Icterus galbula) and Orchard Oriole (Icterus spurius) are members of the blackbird family “Icteridae.” The name oriole originates from their resemblance to the Old World orioles, but these two groups are unrelated.
There are nine species of orioles known to occur in the U.S. Some are resident semi-migratory. The Baltimore and Orchard Orioles occur in the eastern half of the U.S. during the warmer months. They have little geographic overlap with other species of orioles.
These vibrant birds may visit a backyard or park near you during the warmer months of the year.
Molting and Migratory Movements of the Baltimore and Orchard Orioles.
This article focuses on the identification and differences between Baltimore and Orchard orioles’ plumages during the few months they spend in North America.
To identify both orioles by their plumages, one needs to have a basic understanding of their migratory movement and how plumages change over time.
It is interesting to note, though, that plumage changes happen only in juvenile and immature orioles because once birds acquire their adult plumage, this never changes for the rest of their lives.
Baltimore and Orchard Oriole plumage through an annual cycle
Both Baltimore Orioles and Orchard Orioles are sexually dimorphic, meaning that males and females have different plumages.
The plumage of juvenile birds (fledglings of the year) is similar to that of an adult female in Baltimore and Orchard orioles.
The plumage of both species’ young males undergoes dramatic changes and acquires the bright colors of an adult male in two years.
In contrast, young females undergo subtle changes in plumage in the first two years of age and remain mostly similar to adult females.
Migration movements of Baltimore and Orchard Orioles
Both orioles are highly migratory, spending the breeding season in the eastern half of the U.S. and Canada, in North America (N.A.), and the non-breeding season or winter in Mexico and Central America.
In both the breeding and non-breeding seasons, the Baltimore and Orchard Orioles inhabit mostly the same regions and use similar habitats.
Baltimore Oriole Range Map
Time of Arrival and Departure
There are subtle differences in arrival time and departure from the breeding grounds and the time orioles spend in North America.
Baltimore Oriole:
- The Baltimore Oriole arrives in North America later and returns to the Tropics later than the Orchard Oriole.
- According to information obtained from the eBird database, Baltimore Orioles start arriving in North America by mid-April and start returning to the wintering grounds by mid-August. By late September, most Baltimore Orioles are back in Mexico and Central America.
- Baltimore Orioles spend about 5.5 months in the breeding ground in North America.
Orchard Oriole:
- The Orchard Oriole arrives in North America earlier and returns to the Tropics earlier than the Baltimore Oriole.
- According to information obtained from the eBird database, Orchard Orioles start arriving in the U.S. by late April and start leaving back to the wintering grounds by late July. By mid-September, most Orchard Orioles are back in Mexico and Central America.
- Orchard Orioles spend about 4.5 months breeding in North America.
What ages and plumages leave and return in N.A.?
As mentioned above, young orioles of both species acquire their adult plumage two years after hatching. The adult plumage stays the same for the rest of their lives.
The challenge is pinpointing differences between birds under two years of age and adult females of both species.
The following photos focus on field marks that help identify the species, sex, and age of Baltimore Oriole and Orchard Oriole.
This comparative analysis focuses on birds likely to be observed in N.A. and uses the most representative images, notwithstanding that plumages show a good deal of variation at every stage.
Differences between Baltimore and Orchard Orioles
Size Differences
The Baltimore Oriole is larger and heavier than the Orchard Oriole. Differences in size are easier to visualize when both species are side by side. The Orchard Oriole is so small that bird enthusiasts comment that it can be mistaken for a sparrow or even a warbler.
The length of a bird is measured from the tip of the bill to the tip of the tail.
Baltimore Orioles
Length: 8.75 inches.
Wing Span: 11.5 inches.
Weight: 1.2 oz or 36 gr.
Orchard Orioles
Length: 7.25 inches.
Wing Span: 9.5 inches.
Weight: 0.6 oz or 19 gr.
Juvenile Baltimore and Orchard Orioles
Likely to be observed in N.A. from June through October. These are birds hatched in N.A. during the current year.
Baltimore Orioles
Little is known about the plumage of juvenile orioles. Based on plumage differences between male and female Baltimore Orioles, the bird to the left is likely a female, and the one to the right is probably a male.
Upperparts: The top of the head, nape, and mantle are olive. The wings are gray with two whitish-buff wing bars, which are broader than those in Orchard Orioles of similar age. The back, rump, and tail are olive with a yellowish tinge.
Underparts: Warm brown breast that grades to a paler color toward the center of the belly. But this is variable among juvenile males and females.
The bill is dusky with pale gape marks at the base.
The legs and feet are bluish-gray.
The iris or eye color is dark brown.
Orchard Orioles
Overall, the juvenile plumages of Orchard Orioles appear to be less distinctive. Juvenile male and female Orchard Orioles appear to be indistinguishable.
Upperparts: The top of the head, nape, and mantle are olive-yellowing. The wings are gray-brown with two whitish narrow wing bars. The back, rump, and tail are olive-yellowish.
Underparts: Yellow, often brighter yellow than immature and adult females.
The bill is conical and pointy, dusky gray. Notice the pale gape marks of juvenile birds.
The legs and feet are bluish-gray.
The iris or eye color is dark brown.
Immature male Baltimore and Orchard Orioles
Immature Orioles are One-year-old birds returning to the breeding grounds in North America for the first time. Male and female birds of both species have acquired a plumage that precedes the adult plumage. Ornithologists know this pre-adult stage as formative plumage.
Baltimore Oriole
Immature Baltimore Orioles are larger and have proportionally longer tails than immature male Orchard Orioles.
Upperparts: The head, nape, and sides of the neck are olive-orange. The mantle is light gray. The wings are dusky-black with feathers broadly edged with white. It has broad wing bars and shoulders tinged with orange.
Underparts: The throat, breast, and belly are dark orange.
The tail is uniformly yellowish-orange.
The legs and feet are bluish-gray.
Orchard Oriole
Immature Orchard Orioles are slightly smaller and have shorter tails than immature Baltimore Orioles. This comparison is reliable when both species are side by side.
Upperparts: Orchard Orioles have a distinctive solid black chin, throat, and upper neck that resembles a bib. While most one-year-old birds have a black bib and yellow body, some immature males grow chestnut feathers on the breast and patches of black on the head.
The black bib is the best field mark to differentiate immature males from juvenile and female Orchard Orioles.
The head is yellow with a tinge of olive. The lower back and tail are also yellow-olive.
Underparts: The breast and belly are yellow. In some individuals, the breast and belly may show patches of chestnut feathers.
The legs and feet are bluish-gray.
The iris is dark.
Baltimore Oriole
Immature Baltimore Orioles are larger and have proportionally longer tails than immature male Orchard Orioles.
Upperparts: The head, nape, and sides of the neck are olive-orange. The mantle is light gray. The wings are dusky-black with feathers broadly edged with white. It has broad wing bars and shoulders tinged with orange.
Underparts: The throat, breast, and belly are dark orange.
The tail is uniformly yellowish-orange.
The legs and feet are bluish-gray.
Orchard Oriole
Immature Orchard Orioles are slightly smaller and have shorter tails than immature Baltimore Orioles. This comparison is reliable when both species are side by side.
Upperparts: Orchard Orioles have a distinctive solid black chin, throat, and upper neck that resembles a bib. While most one-year-old birds have a black bib and yellow body, some immature males grow chestnut feathers on the breast and patches of black on the head.
The black bib is the best field mark to differentiate immature males from juvenile and female Orchard Orioles.
The head is yellow with a tinge of olive. The lower back and tail are also yellow-olive.
Underparts: The breast and belly are yellow. In some individuals, the breast and belly may show patches of chestnut feathers.
The legs and feet are bluish-gray.
The iris is dark.
Immature female Baltimore and Orchard Orioles
Female Baltimore Oriole
Upperparts: The head, nape, and neck are olive-orange. The mantle is gray. The wings are dusky-gray with feathers broadly edged with white. It has broad white wing bars and grayish shoulders.
Underparts: The breast is olive-orange, grading to grayish towards the middle of the belly. (*) Some immature females have a less marked bicolored belly, while others have a solid orange-brown breast and belly.
The tail is dull orange-yellowish.
The bill is dusky.
The legs and feet are bluish-gray.
Female Orchard Oriole
Upperparts: The top of the head and mantle are yellow with a tinge of olive. The lower back is yellow. The tail is yellowish. The wings are gray-brown with feathers edged with whitish. It has two narrow whitish wing bars.
Underparts: Immature female orchard Orioles are largely yellow and never show the tinges of orange shown by immature female Baltimore Orioles. The cheeks, throat, breast, and belly are yellow.
The bill is dark brown.
The legs and feet are bluish-gray.
Note: Given the similarity and individual variation between an immature and adult female Orchard Oriole, telling them apart based only on the plumage may not be possible.
Adult male Baltimore and Orchard Orioles
Baltimore Oriole
Upperparts: The head and mantle are black. The wings are mostly black with a broad white wing bar and white edging on the secondary wing feathers. The back and rump, usually covered by the folded wings, are bright orange.
Underparts: The breast and belly are bright orange. The tail is mostly orange with a black band and central pair of tail feathers black.
The bill is conical and pointy bluish-dusky with a paler mandible.
The legs and feet are gray.
The iris is dark brown.
Orchard Oriole
Upperparts: The head and mantle are black. The wings are mostly black with chestnut shoulders and a narrow white wing bar. The wing feathers are edged with white. The back and rump, usually covered by the folded wings, are chestnut.
Underparts: The breast and belly are rich (warm) chestnut.
The tail is entirely black with faint whitish edging on the tip.
The bill is conical and pointy, black with a bluish base of the mandible.
The legs and feet are bluish-gray with black claws.
The iris is dark brown.
Adult female Baltimore and Orchard Orioles
Female Baltimore Oriole
Upperparts: The female plumage is variable. The head and back can range from dark brown to dusky brown. The wings are dusky with two white broad wing bars. Females appear to get darker as they age and can have a blackish head, mantle, and blackish wings.
The back and rump, usually covered by the folded wings, are dull orange.
Underparts: Also variable. Some adult females have yellow-orange breasts and brown bellies, while others have uniform warm yellow-orange underparts.
The tail is yellow-olive with yellow undertail coverts.
The bill is bluish-gray, conical, and pointy.
The legs and feet are gray.
The iris is dark brown.
Female Orchard Oriole
Upperparts: The head and mantle are yellow-olive. The wings are gray to dusky gray with pale edging and two distinctive narrow white wing bars. The back and rump, usually covered by the folded wings, are yellowish-olive.
Underparts: The breast and belly are yellow with a tinge of olive.
The tail is yellow-olive.
The bill is conical and pointy, mostly dusky, with a bluish base of the mandible.
The legs and feet are bluish-gray.
The iris is dark brown.
Can habitat use help to identify Baltimore and Orchard Orioles?
The habitat type is one of the most important aspects of bird identification. Birds prefer, and associate with, specific habitat types, which can vary through the annual cycle.
If you know what species are associated with the habitat you are visiting, you can expect to find certain species and rule out species that you know are not associated with a particular habitat.
Unfortunately, habitat type is not a strong indicator to differentiate between Baltimore and Orchard Orioles. Habitat preference in the U.S. is as follows:
- Baltimore Orioles prefer a variety of habitats structurally similar. They favor semi-open habitats with varying densities of trees. They also favor forest edges, second growth, disturbed habitats, and also wooded urban areas. They are particularly attracted to riparian woodlands and deciduous forests.
- The Orchard Oriole also favors semi-open habitats and appears to favor habitats with few trees. Hedges that surround agricultural land appear to be one of the preferred habitats. They also favor forest edges, second growth, disturbed habitats, and also wooded urban areas. They are particularly attracted to riparian woodlands and deciduous forests.
Both oriole species associate with similar habitat types. Neither oriole can be ruled out at specific habitats because they largely overlap at several habitats structurally similar.
Finale Remarks:
Orioles are some of the most popular birds in North America. As bird enthusiasts living in the eastern half of the U.S., we want to know which oriole is visiting our bird feeder or what we see in the field.
Adult male orioles are readily told apart by their striking plumage.
The confusing juvenile, immature, and females of both Baltimore and Orchard Orioles present a challenge.
Based on this article, juvenile, immature, and female Baltimore Orioles show orange color on the underparts that go from dull-olive orange to bright orange in adult females. The white wing bars in Baltimore Orioles are broader than their Orchard Oriole counterpart.
Orchard Oriole never shows orange tones on the underparts. Instead, juvenile, immature, and female Orchard Orioles show yellow to yellow-greenish colors.
Test what is suggested in this article, and let me know if it helped!
References:
- Baltimore Oriole and Orchard Oriole, Life History. All About Birds. The Cornell Lab of Ornithology.
- Gill, Frank (1995). Ornithology. New York: W.H. Freeman.
- The Sibley Guide to Birds. David Allen Sibley, Published by Alfred A. Knopf, 2000.
- The Birds of the World Online. Baltimore Oriole (Icterus galbula), Orchard Oriole (Icterus spurius). Cornell Lab of Ornithology, Ithaca, New York.
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Thank-you! This was very helpful, appreciate all the details which helped me id a female (or immature) Orchard Oriole. I live where Bullock’s Orioles are common, but we do get the occasional Orchard migrant, as well as the (less likely) Baltimore.
Laurel, so glad it helped! Yes a Bullock’s Oriole can be be confusing. I am preparing a mini-guide that includes all North American Orioles. Something similar to the one I did for hummingbirds (link below). In fact, I would appreciate comments on the hummingbird guide format and content 🙂
See it here: http://avianreport.com/hummingbird-identification/
Thank you for stopping by!