This species inhabits open grassland, woodland, and forest near breeding ponds. Non-paedomorphic adults are underground most of the year. During the breeding season, they often are found under rocks and logs. Larvae have been reported to be restricted to shallow areas in lakes with fishes. Adult and larval northwestern salamanders are distasteful to fishes and bullfrogs, allowing coexistence (Leonard et al. 1993). Eggs are laid in ponds, lakes, and slow-moving streams; usually attached to vegetation in shallows (Blaustein et al. 1995) or deeper water, e.g., 0.5–1.0 m below water surface (Nussbaum et al. 1983). It is unclear as to whether or not it is tolerant of habitat disturbance.

This species occurs in the Pacific coast of North America from extreme southeastern Alaska, south through western Canada and northwestern United States of America to the Gualala River in California. It occurs at elevations between sea level and about 3,110 m (Stebbins 2003).

Conservation Actions In-Place
It is uncertain if this species occurs in protected areas. 

Conservation Needed
Needed conservation measures include maintaining forested conditions in areas within at least 200-250 meters of breeding sites. Also, regulatory agencies should attempt to minimize forest fragmentation. 

Research Needed
Research in population size and trends, and population monitoring, are needed.