Flexible life history strategies allow steelhead to persist in a wide variety of coastal watersheds, including arroyo-type streams at the southern limit of this species’ range, which extends to the Tijuana River at the United States- Mexico border. At Topanga Creek, the Resource Conservation District of the Santa Monica Mountains (District) has been monitoring the Southern California steelhead population since 2001. Over the last several years, the Department has partnered with the District, and together, they expanded the existing monitoring program into a full-blown life cycle monitoring station as per the Coastal Monitoring Program. The District has added tagging, con¬ducted growth and age studies, and has experimented with a sonar camera as a means to enhance our knowledge of steelhead in a small southern Califor¬nia stream. As partners, the District and the Department envision expanding their monitoring efforts to include all coastal streams within the entire Santa Monica Mountains population group.