It is found from southeastern Alaska on May Island, through Washington and Oregon south to the mouth of the Gualala River, Sonoma County, California.

Terrestrial adults are mostly fossorial, and are usually active on the surface only during fall rains and spring migrations to their aquatic breeding sites.

Larvae and juveniles consume aquatic invertebrates including snails, worms, and tadpoles.

[9] However, a survey in western Oregon found little correlation between salamander abundance and stand age, so it remains unclear whether A. gracile requires old growth forest to thrive.

Leaving a forest buffer of 200–250 m surrounding breeding sites used by terrestrial adults may preserve optimal environmental conditions for local populations.