The same author found tadpoles feeding primarily on diatoms, which are scraped off the surface of submerged rocks in stream bottoms. Tadpoles also consume small quantities of filamentous green algae and desmids. Large quantities of conifer pollen are consumed seasonally by tadpoles. Individuals have also been found in crevices in spray-drenched cliff walls near waterfalls. During winter individuals are less active, especially inland, and appear to retreat beneath large logs and boulders.
Tadpoles probably spend most of their time attached to such rocks by a large oral sucker.
Mating occurs underwater during much of the April to October activity period. Permanent water is critical because the aquatic larvae require 2 to 3 years to transform. This species is restricted to perennial streams of low temperature in steep-walled valleys with dense vegetation. Intermittent streams are unsuitable. Primarily nocturnal but occasionally abroad during the day.