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Species profile: Spring and summer favorite, Baltimore Oriole
Published: May 1, 2001 The spring's first plaintive hue-lee of the Baltimore Oriole from the top of the elm tree reminds me how dependable birds are. As sure as there is day and night, the Baltimore Oriole will return to this tree every spring to begin its annual quest for a mate and the defense of its territory. Even as I grow older, and my ears less sensitive, I can hear the oriole's familiar whistles, in a sweet minor key, as clearly as I did every spring in my youth. The orioles have always heralded the loveliest time of the year.
And as sure as a male oriole claims the elm, a female will join him a few days later. Almost immediately, the striking orange, black and white birds appear at the orange halves that I have impaled on spikes outside my window.
They arrive in small flocks of a half dozen as if they have flown all the way from Central America and the Caribbean just to sip my citrus. There is something magnetic - as well as metabolic - about the attraction of orioles to citrus fruit in the springtime. Orioles seem to crave it every few minutes during the early phase of the breeding season, which may also explain why they lose interest in oranges later on, as their nesting season winds down. Yet, it is curious that they never seem to lose interest in the sugar water that is also there for their sipping, from the time they arrive in early May until they disappear in mid-September.
It's the oranges and sugar water, plus the birdbaths, that give the orioles such high visibility in my yard throughout their extended visits to the North. Without these attractions, I would be left with only the hue-lee song to remind me of their presence. But the food and water draw the orioles down from the high elm to my patio where I get to see them every few minutes. Their approach is always cautious, as they land first in the dense shrubbery, and then work their way closer to the feeders and the baths. They announce their intentions with a harsh cheh alarm call, and then emerge to show off their brilliant feathers. Even the females are striking in their more subdued flashes of orange. In fact, some females are so brightly colored that they may be confused with first-year males.
Colorful Courtships
It isn't long after their arrival that the pair gets down to the business of raising a family. It begins with a brief period of courtship, in which the male faces the female on a tree branch and stretches upward so she can get the full effect of his brilliant orange breast. Then he bows down as if to extinguish the orange fire with his jet black head and back, only to relight the fire with his brilliant orange rump.
Much of this bowing and displaying by the male is performed while the female is searching the elm tree for just the right hanging, drooping branch from which to build her nest. From it, she soon begins to weave one of the most intricate nests in the avian world. Watching her fashion this grayish, bulbous nursery is one of the fascinations of spring. She works furiously, poking her bill into the mat, picking up loose ends and then weaving them into the mat, as if she has a deadline to meet. The male is supportive, sometimes adding his own materials, and at other times settling into the unfinished nest, pushing his breast against the walls to form the basket shape.
The forming of the nest is a feat of its own, in which the birds push and flutter and mold the shape so vigorously that they shake the limb to which the nest is attached. Though it takes the female as long as eight days to complete her masterpiece, considering the results, it is an amazing accomplishment for such a short period of time. During all this work, the pair make frequent visits to the oranges and sugar water feeders on my patio.
I contribute to the tapestry process by offering cat hair and short pieces of yarn stuffed into an empty suet feeder hanging on a patio tree trunk. Madam Baltimore is more than receptive to my contributions. It's nice to see a part of yourself and the family pet woven into such a fine creation, some 50 feet above the ground.
Preparing for Launch
Few people have ever seen Baltimore Oriole eggs, because of the seclusion and height of the nest. That may be why they lack protective coloration (they are white with the scrawls typical of the eggs of the blackbird family to which they belong). The four or five youngsters hatch after 12 to 14 days of incubation by the female. The male feeds her frequently while she sits, and then he helps her feed the nestlings.
The youngsters need 12 to 14 days to develop and be able to fly when they leave the nest, because of the altitude at which they launch themselves. This requires many trips to the nest by the parents with insects, caterpillars, worms, moths, ants and grasshoppers. These meals-on-wings are delivered as the adults hang almost upside down to reach into the open bills of their only offspring of the year.
Juvenile Baltimores look much like their mothers when they arrive at the sugar-water feeders in midsummer. They then become regulars before leaving for the tropics in mid-September.
In January, when the orioles are enjoying fruits and flower nectar a thousand miles away in the tropics, it's refreshing to look up into the naked elm tree and see their hanging pouch nest. It's so well built that it withstands the harshness of winter while promising the return of its builders come the spring.
Did You Know?
• The Baltimore Oriole was named for George Calvert, an early colonizer of Maryland and first Baron of Baltimore, and his livery or coat of arms, which were orange and black.
• Until recently, the Baltimore Oriole in the East and Bullock's Oriole in the West were considered the same species by scientists, who named them Northern Orioles.
• The female Baltimore Oriole uses a flea market of goods to create a nest: plant fiber (milkweed, Indian hemp), yarn, hair, string, grapevine bark, fine grasses, and in the South, Spanish moss. She stitches a matted pouch, five to eight inches deep, that is attached by its rim to a forked branch. Each time she arrives at the nest with new materials, she uses her bill as a shuttle, poking the strands into the existing mat.
• In terms of their conservation status, Baltimore Orioles do not seem to be danger. In fact, scientists note that orioles do well living near humans. Since they nest readily in open woodlands, woodland edges and urban areas, some human activity appears to have benefited orioles. |
| George H. Harrison writes from his home in Hubertus, Wisconsin. |
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