Baltimore Oriole, Life History, All About Birds - Cornell Lab of Ornithology
- Author: Adam Floyd Apr 04, 2017,
Apr 04, 2017, 6:30
Both SexesLength6.7-7.5 in
17-19 cmWingspan9.1-11.8 in
23-30 cmWeight1.1 -1.4 oz
Relative SizeAbout the size of a Red-winged Blackbird, but slimmer
- Baltimore Orioles (French)
- Baltimore Boser (Spanish)
On their breeding grounds in Eastern and Central-North America, you'll often find Baltimore Orioles high in leafy deciduous trees, but not in deep forests; They prefer open woodland, forest edge, river banks, and small groves of trees. They also forage for insects and fruits in brush and shrubbery. Baltimore Orioles have adapted well to human settlement and often feed and nest in parks, orchards, and backyards. On their winter range in Central America, Baltimore Orioles occupy open woodlands, gardens, and shade-grown coffee and cacao plantations. They often visit flowering trees and vines in search of fruit and nectar.
Baltimore Orioles eat insects, fruit, and nectar. The proportion of each food varies by season: in summer, while breeding and feeding their young, much of the diet consists of insects, which are rich in the proteins needed for growth. In spring and fall, nectar and ripe fruits compose more of the diet; these sugary foods are readily converted into fat, which supplies energy for migration. Baltimore Orioles eat a wide variety of insects, including beetles, crickets, grasshoppers, moths, and flies, as well as spiders, snails, and other small invertebrates. They eat many pest species, including tent caterpillars, gypsy moth caterpillars, fall webworms, spiny elm caterpillars, and the larvae within plant galls. However, orioles can also damage fruit crops, including raspberries, mulberries, cherries, oranges and bananas, and some fruit growers consider these birds to pest. Nesting Facts Nesting Facts Clutch Size3-7 eggsNumber of Broods1 broodsEgg Length0.8-1 in
2.1- 2.5 cmEgg Width0.6-0.7 in
1.5-1.7 cmIncubation Period11-14 daysNestling Period11-14 daysEgg DescriptionPale grayish or bluish white blotched with brown, black, or lavender.Condition at HatchingHelpless, eyes closed, with sparse white down. < / p>
The female chooses a nest site within the territory defended by her mate. She anchors the nest firmly to a fork in the slender upper branches of a tree. Baltimore Orioles often nest in American elms, but will build in other trees, especially maples and cottonwoods. The distinctive nest usually hangs below a branch, but is sometimes anchored along a vertical tree trunk.
- Rising, J.D., and N.J.
Flood. 1998. Baltimore Oriole (Icterus galbula) . The Birds of North America, No. 384. (A. Poole and F. Gill, eds.). The Birds of North America Online, Ithaca, New York.
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