Orioles are a type of colorful songbird found in North and South America. There are several different species of orioles, but the Baltimore Oriole is the most well-known in the United States. The Baltimore Oriole gets its name from the fact that the male has black and orange plumage similar to the heraldic colors of Lord Baltimore, founding proprietor of the Maryland colony. Here is an in-depth look at why orioles are called Baltimore Orioles.
The History Behind the Baltimore Oriole Name
The Baltimore Oriole was first scientifically classified and given its binomial name (Icterus galbula) in 1758 by Carl Linnaeus in the 10th edition of his Systema Naturae. However, the bird was known well before that by early American colonists. European settlers arriving in the 1600s and 1700s noted the bird’s striking plumage and song. The black and orange colors reminded them of the coat of arms belonging to Cecilius Calvert, 2nd Baron Baltimore, the first proprietor of the Maryland colony. Lord Baltimore’s coat of arms featured gold and black patterns. The early colonists started calling the bird the Baltimore bird or Baltimore Oriole as a nod to the Maryland region where the birds were found in abundance.
The Baltimore Oriole was plentiful around Baltimore, Maryland and the surrounding areas. The bird got its common name because of this association with the Baltimore area rather than because it was first discovered there. John James Audubon made the first published reference to the species as the Baltimore Oriole when he painted the bird in 1825. The Baltimore Oriole name became well established afterwards.
The Link Between Lord Baltimore’s Coat of Arms and the Bird’s Plumage
Cecilius Calvert was an English nobleman who helped establish and govern the Maryland colony in the 1600s. He had originally hoped to found the colony as a haven for English Catholics, since the Catholic faith was being persecuted in England at the time. Cecilius became the first Proprietor and Landholder of Maryland in 1632 under a royal charter from King Charles I. He governed the colony until his death in 1675.
The Baltimore family coat of arms featured a shield with black and gold patterns divided into six sections, reflecting Cecilius Calvert’s family lines. There were alternating quadrants of solid gold and black with gold designs etched on the black portions. The colors and divided pattern somewhat resemble the male Baltimore Oriole’s black wings contrasting with its fiery orange-yellow shoulders and underparts.
The Abundance of Baltimore Orioles in Maryland and Nearby Areas
Baltimore Orioles favor open woodland areas and forest edges that provide trees for nesting and flowering plants that supply nectar. The mixed farming and woodlands found in the Chesapeake Bay region and Mid-Atlantic states provided ideal Baltimore Oriole habitat. The birds gravitated to orchards and farms where they could feast on fruit crops and insect pests.
Maryland was historically an agriculture state with abundant orchards and farms crops along with deciduous forests. These prime habitats allowed Baltimore Orioles to flourish. So it made sense for the early settlers to link the bright-colored birds populating the area to the colony’s proprietor Lord Baltimore. Thus the Baltimore Oriole name recognized both the bird’s beauty and its ties to the Maryland area.
Baltimore Oriole Identification and Appearance
The Baltimore Oriole is a medium-sized songbird measuring 17–21 cm (6.7–8.3 in) long with a wingspan of 29–32 cm (11–13 in). Adult males feature a striking orange and black color pattern. The head, back, throat and upper breast are black. The rump, shoulders, belly and undersides of the wings are a vivid orange-yellow. Adult females are mostly yellow-orange on the underparts with an olive-yellowish head and back. Immature birds resemble adult females but are duller in color.
Distinctive Markings
Male Baltimore Orioles have a narrow white bar on their black wings that is visible in flight. Their black tails contrast with the orange-yellow undertail coverts. The thick pointed bill is silver-gray, as are the legs and feet. Their eyes are reddish-orange.
Song and Call
Baltimore Orioles produce a flute-like whistling song made up of slurred high and low notes. Their call is a sharp repetitive chacking noise. They use their wide repertoire of vocalizations to communicate with mates and defend territory.
Range and Habitat
Baltimore Orioles breed in deciduous and mixed forests across much of the eastern United States as far north as Ontario and Quebec in southern Canada. Their breeding range extends west to central Plains states like Nebraska and Kansas. They winter in Florida, Mexico, the Caribbean and northern Central America.
On their breeding grounds, Baltimore Orioles favor open woodlands with tall leafy trees near water. They also inhabit orchards, forest edges, parks and suburban neighborhoods with mature trees. On their wintering grounds, they occupy open forests, palm groves, shade coffee plantations and tree plantations.
Migration
Baltimore Orioles migrate every spring and fall between their breeding and wintering grounds. They are long-distance nocturnal migrants. Spring migration takes place between late March and May. Many of the birds arrive in the southern and central United States in April. Further north they arrive in May and early June. Fall migration typically occurs between late August and early October as they make their way back to Central America and the Caribbean for winter.
Diet
Baltimore Orioles eat insects, fruit and nectar. Caterpillars, beetles, crickets, grasshoppers and spiders are favored insect foods. Wild berries and orchard fruits also make up an important part of their diet. Orioles use their slender pointed bills to pierce the skin of fruits to access the juice and flesh inside. Favorite fruits include mulberries, raspberries, blackberries, oranges, bananas, pears and figs. They visit flowers to drink nectar, especially trumpet vines, fuchsias and nectar-rich blossoms in the tropics.
Baltimore Oriole Behavior and Life Cycle
Baltimore Orioles are active and acrobatic birds with elaborate courtship rituals. They weave hanging nests and vigorously defend their breeding territories. Here are some key facts about their behaviors and breeding biology:
Social Structure
Baltimore Orioles are generally solitary outside of the breeding season. During spring and summer, they form monogamous breeding pairs and live in individual territories.
Courtship Displays
Male Baltimore Orioles perform elaborate courtship displays starting when they arrive at the breeding grounds in spring. Displays include aerial flights and chases, puffing up their feathers, wing waving and various vocalizations. This helps attract mates and define nesting territories.
Nest Building
Female Baltimore Orioles build intricate dangling nests out of plant fibers, hair, string and other materials. The pouch-like nest hangs from the end of a tree branch under the leaves, often near the trunk. Building the nest can take 6-8 days. Both the male and female help incubate the eggs.
Eggs
A single brood may contain 3-7 pale bluish or grayish eggs with dark markings. The female incubates the eggs for 12-14 days before they hatch.
Chicks
Both parents feed the hatchlings regurgitated insects and fruit. The fuzzy nestlings fledge from the nest in about 12-14 days, but still depend on the parents for several more weeks. Some females may raise a second brood.
Territoriality
Baltimore Orioles are highly territorial during the breeding season. Males vigorously chase away intruders, using bill-snapping and aggressive calling. They may mob potential predators like crows, jays and snakes that venture too close to the nest.
Roosting
Baltimore Orioles do not use nest cavities for roosting. They roost hidden in dense foliage of trees and bushes. While migrating they may roost communally in groves of trees.
Longevity
The average lifespan of Baltimore Orioles in the wild is only 1-2 years. However, the maximum recorded lifespan is 13 years for a banded bird recaptured in the wild.
Reasons for Baltimore Oriole Population Decline
Baltimore Oriole populations declined over much of their habitat range during the mid 20th century up through the 1990s. The loss of mature open woodlands reduced their nesting and foraging areas. Pesticide use also harmed oriole numbers by reducing insect prey populations and causing eggshell thinning. Here are some of the main factors behind Baltimore Oriole declines historically:
Habitat Loss
Widespread clearing of forests for agriculture and development eliminated crucial Baltimore Oriole breeding habitat. Fragmentation of remaining woodlands exacerbated the problem by leaving only small isolated habitat patches.
Increased Urbanization
Urban sprawl consumed natural forested areas and brought an influx of new predators like house cats. House cats are estimated to kill over 2 billion birds per year in the U.S. alone.
Invasive Species
Invasive insects tended to outcompete native insects that made up the orioles’ main food source. Invasive plant species also reduced favored fruiting plants.
Pesticides
Pesticide accumulation caused declines in insect prey. It also caused their eggshells to thin, increasing breakage and embryo mortality.
Climate Change
Climate change exacerbated habitat loss in some regions as warmer average temperatures changed forest composition. Extreme weather events also had detrimental impacts by destroying nests and reducing insect numbers.
Baltimore Oriole Conservation Status and Protection
After steep declines, Baltimore Oriole numbers rebounded somewhat thanks to conservation efforts and reduced pesticide use. Their conservation status is now relatively secure, but populations still face threats. Here is a look at the current protection status for Baltimore Orioles:
IUCN Red List Status
The International Union for Conservation of Nature (IUCN) Red List categorizes the Baltimore Oriole as a species of Least Concern. Its global population is estimated at around 15 million individual birds.
State-Level Conservation Status
Baltimore Orioles have no special conservation designation in most states where they occur. But some state wildlife agencies like the Connecticut Department of Energy & Environmental Protection list them as a Species of Special Concern due to continued threats to the birds and their habitats.
Federal Protection
Baltimore Orioles are protected under the Migratory Bird Treaty Act of 1918 since they are migratory songbirds. This law makes it illegal to harm or kill Baltimore Orioles, destroy active nests or eggs, or possess any parts of the birds such as feathers without permits.
Habitat Protection Efforts
Protecting remaining mature open forests and reforesting cleared areas provides crucial breeding grounds. Reducing insecticide use helps maintain the food supply. Backyard birding initiatives also benefit Baltimore Orioles by providing food sources and nesting sites.
Fun Facts About Baltimore Orioles
Baltimore Orioles exhibit some interesting behaviors and traits. Here are a few fun facts about these colorful songbirds:
Acrobatic Freestylers
Baltimore Orioles make amazing aerial acrobatic maneuvers, flying in loops, dive-bombing and freestyling just for fun. Males put on aerial displays during courtship.
Beautiful Basket-Nest Builders
Female Baltimore Orioles weave incredible hanging nests that look like baskets, with entries at the top. They strip fibers from plants, vines and even man-made materials like twine.
Orange Tropical Treats
Baltimore Orioles winter in Central America and Mexico where they enjoy the local tropical fruits. Oranges, mangos and bananas become part of their diet.
Musical Mimics
Baltimore Orioles have a vast repertoire of vocalizations. They can also mimic sounds like those of frog, hawk and kingfisher calls.
Ruby-eyed Gemstones
Baltimore Orioles have striking reddish-orange eyes the color of ruby gems. The eye color stands out against their black and orange plumage.
Sweet-Teethed Sweeties
Baltimore Orioles have a sweet tooth and love nectar from flowers and sugars from ripe fruits. They slash oranges and pierce other fruits to get the sugary juices.
Masked Marauders
The black head markings on male Baltimore Orioles look like Zorro’s mask. Females and juveniles have yellow “masks”. Their masks may help camouflage in the dappled light of leafy trees.
Shiny Silver Swordsmen
Male Baltimore Orioles have a silver-gray beak like a sword for battling other males and piercing fruit. Females have duller grayish-brown bills better for camouflage.
Apex Insectivores
Baltimore Orioles devour vast amounts of caterpillars, spiders, beetles, ants and other insects. This helps control insect pest populations, especially in orchards.
Conclusion
Baltimore Orioles get their common name from their black and orange coloration bearing resemblance to the heraldic colors on Lord Baltimore’s coat of arms. The birds were also originally abundant around Baltimore, Maryland where early colonists first encountered them. Though their populations declined over the years, active conservation measures have helped Baltimore Orioles recover. These ornate songbirds continue to add a splash of color to the spring landscape across eastern North America.