One of the first migratory birds to return to Yellowstone each year is the mountain bluebird. Mountain bluebirds inhabit the western half of North America and prefer open habitat.
The female mountain bluebird is mostly pale and grey in color with only a hint of the blue coloration of the male. The female builds the nest by herself, typically in a cavity or nesting box.
The males are bright blue with out the reddish coloration on their underparts that the eastern and western bluebirds exhibit. Mountain bluebirds will often compete with western bluebirds for nesting spaces and territory. In the few areas where their range overlaps that of the eastern bluebird the mountain bluebirds tend to dominate.
We spotted mountain bluebirds at locations all around the park, however the most cooperative ones that we found were hanging around the Old Faithful complex.