A trail at 7,000 feet high in the California mountains (Big Bear) attracts the cheerful little Mountain Chickadees.
Note the distinctive white supercilium (eyebrow). They first nested in bluebird sized boxes mounted to the side of the cabin for the past several years. The trail was later expanded to include boxes hanging from tree branches at about 15 feet high and built with 1.25" holes slightly sanded.
Mountain Chickadees — Big Bear, Calif. Trail (2000)
More small boxes were added prior to the 2002 season with the intent to increase the mountain chickadee population. However, the extra boxes were snapped up by Pygmy Nuthatches rather than the intended guests.
A leucocystic Mountain Chickadee came for seed during Dec. 2002 and a photo is shown below next to a comparison photo of a mountain chickadee with normal coloring.
Two more comparison photos below: