Marbled murrelets (Brachyramphus marmoratus) range from Alaska to California and are federally listed under the U.S. Endangered Species Act as threatened in Washington, Oregon, and California (USFWS 1997). Recovery of the murrelet depends, in large part, on conservation and restoration of breeding habitat on federally managed lands. Conservation of murrelet nesting habitat was one of the major objectives of the Northwest Forest Plan (hereafter the Plan). Under the Plan, the goal was to conserve and restore nesting habitat on federally administered lands that will sustain a viable murrelet population (FEMAT 1993). Monitoring is an essential component of the Plan and is meant to help managers understand the degree to which the Plan is meeting this objective. This report describes the methods used to assess the status and trend of the marbled murrelet in the portion of its range covered by the Plan.