
Baltimore Orioles measure 7 – 8 1/2 inches long. The male bird is black with orange underparts, rump, shoulders, and sides of the tail. His wings have 2 white wing bars. The female Baltimore Oriole looks quite different than the male. She is olive above, and yellowish below with 2 white wing bars. This particular Oriole bird is found east of the Rockies.

The breeding season begins in late April to early May. The males arrive 2 or 3 days before the females and begin claiming their territories. You’re likely to hear them singing from treetops in their effort to attract a mate. Their singing is almost constant until they mate with a female. Unlike the Northern Mockingbird though, these birds do not sing at night. Generally, any singing late in the season is from unmated or immature birds. Once the birds have found a mate they defend their territory and begin nesting.
The female selects a site for the nest, usually in a deciduous tree, often a tall one. Orioles prefer trees such as Elm, Cottonwood, or Maples to build their nest. The nest is typically located at the end of a branch, which provides some protection against predators. The female gathers materials for the nest, which can include plant, animal, and even human-made materials. This often includes grass, bark, hair, and twine. She may also use spider silk as a binding agent. The female weaves the nest, creating a small cup shape. She starts by weaving a loop around a twig. Then she weaves additional material, including long grasses and strips of bark, in and out of the loop. The weaving process can take as long as a week.

Once the basic structure is complete, the female lines the inside of the nest with soft materials, such as plant down, fur, or feathers, to provide a comfortable and warm environment for the eggs and chicks. The outside of the nest is often decorated with gray and white lichen, which helps to camouflage it against the tree. Nest can be anywhere from 6 to 90 feet above the ground.
While it’s quite common for them to return each year to the same territory, they will not use the same nest. They often take parts of the old nest to build a new one, so you may see them at the old nest site. Bird watchers will find the best viewing of the Baltimore Oriole’s nest when the leaves are off the trees. You’ll see them at the end of branches high in shade trees.
The preferred habitat of Orioles is in open woodlands of deciduous trees near parks, gardens, and suburban settings. In this tightly woven hanging nest, the female lays 3 to 6 pale blue with dark marks eggs. Incubation of the eggs is done by the female with the male always close by and watching. Incubation will last 12 to 14 days and the young birds will leave the nest in 12 to 14 days after hatching.
Baltimore Orioles nest only once each season and do not use birdhouses. Cowbirds have a difficult time laying eggs in the Oriole’s nest but still do. Orioles can tell the difference between their eggs and Cowbird’s eggs. Either the Oriole will eat the Cowbird’s eggs, or eject them from the nest.
The main diet of the Baltimore Oriole consists of insects, fruits, and flower nectar. At the feeding station orange halves or grape jelly placed in a shallow bowl will draw them in. Another option is by providing a sugar-water mixture. 1 part sugar to 4 parts water. No need to boil the sugar-water mixture. Replace often during hot weather.

Often we’re asked “What happened to our Oriole birds”? “They were here every day eating our oranges and grape jelly and now they’re gone”. The simple answer is that Orioles often disappear from feeders because they switch to a protein-rich diet while nesting and feeding their young to ensure healthy growth. This means they are hunting insects instead of visiting your feeders. They also may have started migrating south. Don’t worry, sometimes the adults will bring their young to the feeders once they’ve left the nest. So be prepared for a return after a 4-week absence.
Spring migration begins in April when male Baltimore Orioles begin to arrive at their breeding grounds roughly East of the Rockies. The winter migration to the South can begin as early as July, which is much earlier than most species. Still, you may see some Orioles well into September or a little later in their Southern range.
SOURCE: WILD-BIRD-WATCHING.COM



































