Bullock’s Oriole (Icterus bullockii) is the most common oriole in Montana. The Orchard Oriole and Baltimore Oriole are seen mostly in Eastern Montana, and the Hooded Oriole is a rare spring visitor. Bullock’s Oriole is usually spotted among cottonwood and willow trees as the species likes open woodlands and riparian woodlands. John James Audubon described the bird’s eating as “gleaning for small larvae, or sipping the nectareous juices of the opening blossoms of the trees they delight to frequent.” Bright orange cheeks and chest are marks of the otherwise mostly black adult male. The female and younger birds tend toward yellow and gray rather than orange and black. Bullock’s Oriole has never been numerous in Gallatin County, but it is a regular early summer guest.
The image is a detail from Plate 388 of John J. Audubon’s Birds of America. Imagine source: https://www.audubon.org/birds-of-america/nuttalls-starling-yellow-headed-troopial-bullocks-oriole