Baltimore Oriole Overview: Identification and Behavior

The Baltimore oriole is a brilliantly colored orange songbird welcome in many yards and gardens. Once combined with its western counterpart as a single species, the northern oriole, the Baltimore oriole today is recognized as a distinct species and is a member of the Icteridae bird family. As the state bird of Maryland, this oriole is very familiar, but there are always more Baltimore oriole facts to learn.

Fast Facts

• Scientific Name: Icterus galbula
• Common Name: Baltimore Oriole, Northern Oriole
• Lifespan: 10-12 years
• Size: 6.5-8 inches
• Weight: 28-42 grams
• Wingspan: 3.5-4 inches
• Conservation Status: Least concern

Baltimore Oriole Identification

Male and female Baltimore orioles look very different. Males have a black hood, back, and throat over bold orange underparts and rump, though some birds are paler and may look more yellow than orange. The yellow-orange color extends onto the shoulder in a thick wedge over black wings. Wings have a single white bar and white feather edging. The black tail has yellow or orange underneath. Instead of black, females show olive-brown coloration and more mottling. Females are more likely to have lighter yellow coloration where the males show orange, and females have two white wing bars. As females age, their coloration becomes darker, but they do not show as distinct of a hood as males. For both genders, the eyes are black and the legs and feet are blackish-gray. Juveniles look similar to adult females, and young males will appear dingy and mottled as they mature into their adult plumage when they are just over a year old.

Baltimore orioles have a distinctive two-pitch undulating slow warble, though the speed of the song may change during one call. Other calls include high chips and chirps as well as a rapid dry rattle.

Habitat and Distribution

Baltimore orioles are popular spring and summer birds in open deciduous forests and riparian areas in the eastern United States as well as in suburban parks, orchards, and yards. Populations extend as far west as the Great Plains and eastern Dakotas, Nebraska, Kansas, Oklahoma, and Texas, as well as the southern half of eastern Canadian provinces.

Migration Pattern

These colorful songbirds are complete migrants, leaving their spring and summer breeding range for a completely different location in the fall and winter. Baltimore orioles migrate to Central and South America, though limited populations spend winters in Florida, along the edge of the southeastern United States, and along the Gulf Coast of Mexico.

Behavior

These orioles can be very shy, solitary birds for most of the year, though after the nesting season they are likely to appear in pairs or small mixed flocks, particularly while foraging in the fall and winter.

Diet and Feeding

Baltimore orioles feed in shrubs, bushes, and trees, hunting for insects or picking through flowers. Largely frugivorous, these birds eat a wide variety of fruit, including berries, but are especially attracted to oranges. Caterpillars, spiders, and other insects, as well as nectar, are also part of their diet. In the backyard, they prefer feeding stations away from the busiest areas, preferably in a shaded area near secure shelter.

Nesting

Baltimore orioles are monogamous birds that pair together after elaborate courtship rituals that include tail and wing spread displays and bowing to show off plumage colors. Wing quivering is often part of these displays as well. The nest is a dangling pouch woven from thin plant fibers, animal fur, yarn, string, and hair, and is lined with grass or wool. The female builds the nest, and it is positioned 25-35 feet above the ground, though some can be found much higher. Almost all Baltimore oriole nests are found in deciduous trees.

Where the Baltimore oriole’s range overlaps with the Bullock’s oriole, interbreeding and hybridization is common. These birds are occasional hosts to brown-headed cowbird eggs but are usually able to recognize the unwanted egg and remove it from their nest.

Eggs and Young

A mated pair of Baltimore orioles will produce one brood of 3-7 oval-shaped, gray-white or pale blue eggs per year. The eggs show dark blackish-brown blotches or squiggles at the large end. The female oriole will incubate the eggs for 12-14 days. Both parents feed the chicks for an additional 12-14 days until the young birds can safely leave the nest.

Baltimore Oriole Conservation

While these orioles are not threatened or endangered, their populations are slowly declining. Habitat loss, particularly in their winter range, is a distinct problem, but supporting shade-grown coffee and bird-friendly chocolate can help preserve that habitat. Overuse of insecticides in fruit plantations is another problem, both because the insect populations are essential to orioles' diets and pesticides on fruit could lead to inadvertent poisoning. In some areas, these birds may be considered a pest in fruit plantations and could be persecuted.

Tips for Backyard Birders

Though shy, Baltimore orioles will readily come to yards that provide their favorite foods, including grape jelly, orange halves, nectar, and suet. Birders should avoid spraying pesticides that can eliminate insects as a food source, and hanging hair or short string sections can help attract orioles to nest nearby. Adding a fruit tree to the yard is another way to help attract these birds, particularly with cherries or mulberries.

How to Find This Bird

Despite its brilliant color, Baltimore orioles can be surprisingly difficult to find in the field because they are relatively solitary. Visiting fruit-rich habitats such as orchards and gardens can increase a birder's chances of finding a Baltimore oriole. Late summer, after the breeding season, is the best time to see Baltimore orioles when populations are larger with newly-hatched birds and mature birds are no longer as secretive about nesting.

Baltimore Orioles in Culture

The Baltimore oriole is the state bird of Maryland, but it has more of a connection to Maryland than just being found in the state. The bird is named for the colorful coat of arms carried by George Calvert, the first Lord Baltimore in the 17th century, who was the nobleman charged with chartering what would become Maryland. The Baltimore oriole was officially designated as Maryland's state bird in 1947.

Of course, the bird is also popular as a mascot, most notably with the Baltimore Orioles major league baseball team. The officially designated Oriole Bird "hatched" on April 6, 1979, and has been the team's fun feathered emblem ever since.

Explore More Species in This Family

All orioles can be fascinating birds, and interested birders will also want to check out similar birds such as the Venezuelan troupial, which looks nearly identical to the Baltimore oriole.