View in other NatureServe Network Field Guides
Bullock's Oriole -
Native Species Global Rank
Agency Status USFWS
Listen to an Audio Sample
It seems your browser doesn't support HTML5 audio. Here is a
to the audio instead Copyright by: The Macaulay Library at the Cornell Lab of Ornithology, Ithaca, NY, all rights reserved.
Older males have bright black and orange-yellow plumage. The crown, nape, back, and scapulars being black; the remainder of the head and underparts are orange-yellow in color. The younger males resemble females, which are grayish-green and yellow, with black on the throat (Rising and Williams 1999).
For a comprehensive review of the conservation status, habitat use, and ecology of this and other Montana bird species, please see
Marks et al. 2016, Birds of Montana.
Western Hemisphere Range
Observations in Montana Natural Heritage Program Database
Number of Observations:
(Click on the following maps and charts to see full sized version)
Map Help and Descriptions
SUMMER (Feb 16 - Dec 14)
Direct Evidence of Breeding
Indirect Evidence of Breeding
No Evidence of Breeding
WINTER (Dec 15 - Feb 15)
Not Regularly Observed
(Observations spanning multiple months or years are excluded from time charts)
In the Bozeman area, normal migration periods are from May 17 to May 30 with no discernible fall movement.
Prefers open woodland areas, especially riparian (river) woodlands with large cottonwoods, sycamores, and willows. During spring and fall migration it is found in a variety of open woodland and urban parklands and tall shrubland (Rising and Williams 1999).
Ecological Systems Associated with this Species
Details on Creation and Suggested Uses and Limitations
How Associations Were Made
We associated the use and habitat quality (common or occasional) of each of the 82 ecological systems mapped in Montana for
vertebrate animal species that regularly breed, overwinter, or migrate through the state by:
Using personal observations and reviewing literature that summarize the breeding, overwintering, or migratory habitat requirements of each species (Dobkin 1992, Hart et al. 1998, Hutto and Young 1999, Maxell 2000, Foresman 2012, Adams 2003, and Werner et al. 2004);
Evaluating structural characteristics and distribution of each ecological system relative to the species' range and habitat requirements;
Examining the observation records for each species in the state-wide point observation database associated with each ecological system;
Calculating the percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system to get a measure of "observations versus availability of habitat".
Species that breed in Montana were only evaluated for breeding habitat use, species that only overwinter in Montana were only evaluated for overwintering habitat use, and species that only migrate through Montana were only evaluated for migratory habitat use.
In general, species were listed as associated with an ecological system if structural characteristics of used habitat documented in the literature were present in the ecological system or large numbers of point observations were associated with the ecological system.
However, species were not listed as associated with an ecological system if there was no support in the literature for use of structural characteristics in an ecological system,
point observations were associated with that system.
Common versus occasional association with an ecological system was assigned based on the degree to which the structural characteristics of an ecological system matched the preferred structural habitat characteristics for each species as represented in scientific literature.
The percentage of observations associated with each ecological system relative to the percent of Montana covered by each ecological system was also used to guide assignment of common versus occasional association.
If you have any questions or comments on species associations with ecological systems, please contact the Montana Natural Heritage Program's Senior Zoologist.
Suggested Uses and Limitations
Species associations with ecological systems should be used to generate potential lists of species that may occupy broader landscapes for the purposes of landscape-level planning.
These potential lists of species should not be used in place of documented occurrences of species (this information can be requested at:
) or systematic surveys for species and evaluations of habitat at a local site level by trained biologists.
Users of this information should be aware that the land cover data used to generate species associations is based on imagery from the late 1990s and early 2000s and was only intended to be used at broader landscape scales.
Land cover mapping accuracy is particularly problematic when the systems occur as small patches or where the land cover types have been altered over the past decade.
Thus, particular caution should be used when using the associations in assessments of smaller areas (e.g., evaluations of public land survey sections).
Finally, although a species may be associated with a particular ecological system within its known geographic range, portions of that ecological system may occur outside of the species' known geographic range.
Adams, R.A. 2003. Bats of the Rocky Mountain West; natural history, ecology, and conservation. Boulder, CO: University Press of Colorado. 289 p.
Dobkin, D. S. 1992. Neotropical migrant land birds in the Northern Rockies and Great Plains. USDA Forest Service, Northern Region. Publication No. R1-93-34. Missoula, MT.
Foresman, K.R. 2012. Mammals of Montana. Second edition. Mountain Press Publishing, Missoula, Montana. 429 pp.
Hart, M.M., W.A. Williams, P.C. Thornton, K.P. McLaughlin, C.M. Tobalske, B.A. Maxell, D.P. Hendricks, C.R. Peterson, and R.L. Redmond. 1998. Montana atlas of terrestrial vertebrates. Montana Cooperative Wildlife Research Unit, University of Montana, Missoula, MT. 1302 p.
Hutto, R.L. and J.S. Young. 1999. Habitat relationships of landbirds in the Northern Region, USDA Forest Service, Rocky Mountain Research Station RMRS-GTR-32. 72 p.
Maxell, B.A. 2000. Management of Montana's amphibians: a review of factors that may present a risk to population viability and accounts on the identification, distribution, taxonomy, habitat use, natural history, and the status and conservation of individual species. Report to U.S. Forest Service Region 1. Missoula, MT: Wildlife Biology Program, University of Montana. 161 p.
Werner, J.K., B.A. Maxell, P. Hendricks, and D. Flath. 2004. Amphibians and reptiles of Montana. Missoula, MT: Mountain Press Publishing Company. 262 p.
Commonly Associated with these Ecological Systems
Forest and Woodland Systems
Human Land Use
Shrubland, Steppe and Savanna Systems
Wetland and Riparian Systems
Occasionally Associated with these Ecological Systems
Forest and Woodland Systems
Human Land Use
Recently Disturbed or Modified
Shrubland, Steppe and Savanna Systems
Wetland and Riparian Systems
Eats mostly insects, especially butterfly and moth larvae and pupae, grasshoppers and crickets, beetles and other insects (Rising and Williams 1999).
Nests are typically pensile, often suspended from a few thin branches. Eggs are oval. Clutch size ranges from 3 to 7 eggs. (Rising and Williams 1999). Statewide, nesting is from May 29 to August 12.
Literature Cited Above
Legend: View Online Publication Marks, J.S., P. Hendricks, and D. Casey. 2016. Birds of Montana. Arrington, VA. Buteo Books. 659 pages. 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.). Academy of Natural Sciences of Philadelphia and American Ornithologists’ Union. Additional References
Legend: View Online Publication Do you know of a citation we're missing? American Ornithologists’ Union [AOU]. 1973. Thirty-second supplement to the American Ornithologists’ Union Check-list of North American birds. Auk 90(2):411-419. American Ornithologists’ Union [AOU]. 1995. Fortieth supplement to the American Ornithologists’ Union Check-list of North American birds. Auk 112:819-830. American Ornithologists’ Union [AOU]. 1998. Check-list of North American birds, 7th edition. American Ornithologists’ Union, Washington, D.C. 829 p. Bent, A.C. 1958. Life histories of North American blackbirds, orioles, tanagers, and their allies. U.S. Natl. Mus. Bull. 211. Washington, D.C. Bird Conservancy of the Rockies. 2017. Pocket Guide to Northern Prairie Birds. Brighton, CO: Bird Conservancy of the Rockies. 98 p. Bramblett, R.G., and A.V. Zale. 2002. Montana Prairie Riparian Native Species Report. Montana Cooperative Fishery Research Unit, Montana State University - Bozeman. Cameron, E. S. 1907. The birds of Custer and Dawson counties, Montana. Auk 24(3):389-406. Casey, D. 2005. Rocky Mountain Front avian inventory. Final report. Prepared for the U.S. Fish and Wildlife Service and The Nature Conservancy by the American Bird Conservancy, Kalispell, Montana. Davis, C.V. 1961. A distributional study of the birds of Montana. Ph.D. Dissertation. Corvallis, OR: Oregon State University. 462 p. Dobkin, D.S. 1994. Conservation and management of neotropical migrant landbirds in the Northern Rockies and Great Plains. Univ. Idaho Press, Moscow, Idaho. 220 pp. ECON, Inc. (Ecological Consulting Service), Helena, MT., 1979, Annual wildllife report of the Colstrip Area for 1979, including a special raptor research study. Proj. 216-85-A. March 1, 1980. Ehrlich, P., D. Dobkin, and D. Wheye. 1988. The birder’s handbook: a field guide to the natural history of North American birds. Simon and Schuster Inc. New York. 785 pp. Eng, R.L. 1952. A two-summer study of the effects on bird populations of chlordane bait and aldrin spray as used for grasshopper control. M.Sc. Thesis. Bozeman, MT: Montana State University. 27 p. Gillihan, SW. and T. VerCauteren. 2015. Pocket Guide to Prairie Birds. Brighton, CO: Bird Conservancy of the Rockies. 91 p. Goodell, J. 2012. Morse Land Company Breeding Bird Inventory And Analysis. High Desert Museum. Bend, OR. 42 pp + Appendices. Hays, R., R.L. Eng, and C.V. Davis (preparers). 1984. A list of Montana birds. Helena, MT: MT Dept. of Fish, Wildlife & Parks. Hendricks, P., G.M. Kudray, S. Lenard, and B.A. Maxell. 2007. A Multi-Scale Analysis Linking Prairie Breeding Birds to Site and Landscape Factors Including USGS GAP Data. Helena, Mont: Montana Natural Heritage Program. Hendricks, P., S. Lenard, D.M. Stagliano, and B.A. Maxell. 2013. Baseline nongame wildlife surveys on the Fort Peck Indian Reservation. Report to the Assiniboine and Sioux Tribes of the Fort Peck Indian Reservation. Montana Natural Heritage Program, Helena, MT. 83 p. Johnsgard, P.A. 1979. Birds of the Great Plains: breeding species and their distribution. University of Nebraska Press, Lincoln. 539 pp. Joslin, Gayle, and Heidi B. Youmans. 1999. Effects of recreation on Rocky Mountain wildlife: a review for Montana. [Montana]: Montana Chapter of the Wildlife Society. Knopf, F.L. 1985. Significance of riparian vegetation to breeding birds across an altitudinal cline. Res. Pap. INT-442. Ogden, UT: U.S.D.A. For. Serv., Intermountain Research Station. 12pp. OR U.S.D.A, For. Serv. Rocky Mountain Forest and Range Exper. Stat. Gen. Tech. Report RM-254. 184 pp. Land & Water Consulting, Inc., Missoula, MT., 2002, Montana Dept. of Transportation Wetland Mitigation Monitoring Report, Year 2001: Musgrave Lake, Montana. Proj. No. 130091.019. July 2002. In 2001 Wetland Mitigation Monitoring Reports, Vol. II. Lenard, S., J. Carlson, J. Ellis, C. Jones, and C. Tilly. 2003. P. D. Skaar's Montana bird distribution, 6th edition. Montana Audubon, Helena, MT. 144 pp. Maxell, B.A. 2016. Northern Goshawk surveys on the Beartooth, Ashland, and Sioux Districts of the Custer-Gallatin National Forest: 2012-2014. Montana Natural Heritage Program. Helena, MT. 114pp. Maxim Technologies, Inc., 2002, Western Energy Company Rosebud Mine, Colstrip, Montana: 2002 Annual Wildlife Monitoring Report; December 1, 2001 - November 30, 2002. Febr. 24, 2002. McWethy, D.B. 2007. Bird response to landscape and pattern disturbance across productivity gradients in forests of the Pacific Northwest. Ph.D. Dissertation. Bozeman, MT: Montana State University. 184 p. Montana Bird Distribution Committee. 2012. P.D. Skaar's Montana bird distribution. 7th Edition. Montana Audubon, Helena, Montana. 208 pp. + foldout map. Newlon, K.R. 2005. Demography of Lewis's Woodpecker, breeding bird densities, and riparian Aspen integrity in a grazed landscape. M.Sc. Thesis. Bozeman, MT: Montana State University. 101 p. Oechsli, L.M. 2000. Ex-urban development in the Rocky Mountain West: consequences for native vegetation, wildlife diversity, and land-use planning in Big Sky, Montana. M.Sc. Thesis. Montana State University, Bozeman. 73 p. Rundquist, V.M. 1973. Avian ecology on stock ponds in two vegetational types in north-central Montana. Ph.D. Dissertation. Bozeman, MT: Montana State University. 112 p. Sater, S. 2022. The insects of Sevenmile Creek, a pictorial guide to their diversity and ecology. Undergraduate Thesis. Helena, MT: Carroll College. 242 p. Saunders, A. A. 1912. A horseback trip across Montana. Condor 14(6):215-220. Saunders, A.A. 1914. The birds of Teton and northern Lewis & Clark counties, Montana. Condor 16:124-144. Sibley, D. 2014. The Sibley guide to birds. Alfred A. Knopf, New York, NY. 598 pp. Skaar, P.D. 1969. Birds of the Bozeman latilong: a compilation of data concerning the birds which occur between 45 and 46 N. latitude and 111 and 112 W. longitude, with current lists for Idaho, Montana, Wyoming, impinging Montana counties and Yellowstone National Park. Bozeman, MT. 132 p. Stewart, R.E. 1975. Breeding birds of North Dakota. Tri-College Center for Environmental Studies, Fargo, North Dakota. 295 pp. Terres, J.K. 1980. The Audubon Society encyclopedia of North American birds. Alfred A. Knopf, New York. 1109 pp. Vold, S.T. 2018. Effects of livestock grazing management on the ecology of grassland birds and their predators in a northern mixed-grass prairie ecosystem. M.Sc. Thesis. Bozeman, MT: Montana State University. 176 p. Waage, Bruce C., 1995, Western Energy Company Rosebud Mine, Colstrip, Montana:1994 Annual Wildlife Monitoring Report; December 1, 1993 - November 30, 1994. February 27, 1995. Walcheck, K.C. 1970. Nesting bird ecology of four plant communities in the Missouri River Breaks, Montana. Wilson Bulletin 82(4):370-382. WESTECH Env. Services, Inc., Helena, MT., 2000, Reconnaissance of Wildlife and Fisheries Resources at the Ruby Garnet Alder Gulch Property. May 24, 2000. In Application for an Operating Permit and Proposed Plan of Operations, Alder Gulch Mine Project, Mad White, C.M., N.J. Van Lanen, D.C. Pavlacky Jr., J.A. Blakesley, R.A. Sparks, J.M.Stenger, J.A. Rehm-Lorber, M.F. McLaren, F. Cardone, J.J. Birek and D.J. Hanni. 2011. Integrated monitoring of bird conservation regions (IMBCR): 2010 Annual Report. Brighton, CO: Rocky Mountain Bird Observatory. 387 p. Wright, P.L. 1996. Status of rare birds in Montana, with comments on known hybrids. Northwestern Naturalist 77(3):57-85. Web Search Engines for Articles on "Bullock's Oriole"
Additional Sources of Information Related to "Birds"