- 6.7–7.5 in
- 12.2 in
- 1–1.5 oz
- Northern Oriole (in part)
- Oriole de Bullock, Oriole à ailes blanches (French)
- Bolsero calandria (Spanish)
- The Bullock's Oriole hybridizes extensively with the Baltimore Oriole where their ranges overlap in the Great Plains. The two species were considered the same for a while and called the Northern Oriole, but recently, they were separated again. Molecular studies of the oriole genus indicate that the two species are not very closely related.
- The Bullock's Oriole's nest is not always placed in territory where the male advertises.
- Both sexes of Bullock's Oriole sing, but the males and females sing different songs. The song of the female is similar to that of the male, but it ends differently and with harsher notes. Early in nesting period, and before and during nest-building, the female sings regularly, and may sing more than the male.
- The oldest recorded Bullock's Oriole was a male, and at least 8 years, 11 months old, when it was recaptured and rereleased during banding operations in Colorado.
Riparian and open woodlands, or woodlots with tall trees, including parklands. Winters in riparian woodlands and woodland edge, with some in pine, pine-oak, or fir forests.
Caterpillars, fruits, insects, spiders, and nectar.
- Clutch Size
- 2–7 eggs
- Egg Description
- Pale bluish or grayish white, sometimes with purplish tint, splotched and scrolled with a few to many fine, purplish brown lines.
- Condition at Hatching
- Helpless with sparse white down.
Hanging nest, neatly woven of hair (especially horsehair), twine, fibers, grasses, and wool, lined with cottonwood or willow cotton, wool, or feathers. Placed in isolated trees, at edges of woodlands, along watercourses, in shelterbelts, and in urban parks, often near water.
Gleans and probes in trees and flowers for insects and nectar. Visits feeders for sugar water.
Bullock's Oriole are widespread and common, but populations declined by 29% between 1966 and 2014, according to the North American Breeding Bird Survey. Partners in Flight estimates a global breeding population of 7 million with 86% spending some part of the year in the U.S., 96% in Mexico, and 3% breeding in Canada. They rate an 11 out of 20 on the Continental Concern Score and are not on the 2014 State of the Birds Watch List.
- Rising, J. D., and P. L. Williams. 1999. Bullock's Oriole (Icterus bullockii). In The Birds of North America, No. 416 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.
- North American Bird Conservation Initiative, U.S. Committee. 2014. State of the Birds 2014 Report. U.S. Department of Interior, Washington, DC.
- Partners in Flight. 2012. Species assessment database.
- USGS Patuxent Wildlife Research Center. 2015. Longevity records of North American Birds.
- USGS Patuxent Wildlife Research Center. 2014. North American Breeding Bird Survey 1966–2014 Analysis.