Canary Spring © 2010 Bo Mackison

Not all of the terraces at Mammoth Hot Springs are chalky white and dry. Canary Spring at the top of the Lower Terrace flows with heated water that has been moving underground for many years. The vibrant colors – oranges, yellows, dark reds – are caused by cyanobacteria and algae mats. They depend on a stable flow of hot water to stay alive. When the water flow decreases or stops, the micro-organisms die and the colors turn into stark white travertine which covers much of the terraced landscape.

Canary Spring is near the top of the Main Terraces, reached by walking a series of boardwalks and stairways through the Mammoth Hot Springs or by driving the Lower Terrace Overlook Road just south of Mammoth.

Just one more thermal feature photographed in Yellowstone National Park.