Rainbow Starfrontlets often engage in aerial chases above the forest canopy, making a high-pitched chatter as they go after one another. When in normal flight, they vocalize with sharp tzips. The glittering, rainbow forehead of males can vary considerably in color, making the extensive chestnut of both sexes, long bill, and large size more diagnostic. Notable color variation also exists among the six subspecies. These starfrontlets frequent both humid and dry cloud forests, gardens, and scrubby areas, often foraging between 2 and 4 meters off the ground. Although considered locally common, these hummingbirds are potentially vulnerable because of their restricted range in middle-upper elevations from southern Ecuador to northern Peru. They are usually found at lower elevations than Buff-winged Starfrontlets in areas where the two species overlap.