Xantus' Murrelet, Sythliboramphus hypolechus II: Assessment of Listing Status

William J. Sydeman
Point Reyes Bird Observatory, Marine Science Division, 4990 Shoreline Hwy., Stinson Beach, CA 94970; 415-868-1221x19; wjsydeman@prbo.org

Nadav Nur
Point Reyes Bird Observatory, Marine Science Division, 4990 Shoreline Hwy., Stinson Beach, CA 94970; 415-868-1221x15; nadavnur@prbo.org

Abstract
We considered the status of Xantus' Murrelet (Synthliboramphus hypoleucus), a rare seabird of the western United States and Mexico, under the World Conservation Union quantitative criteria for listing as vulnerable, threatened and endangered. Based on World Conservation Union Criterion B, Xantus' Murrelet qualifies for listing as vulnerable, although our information base is incomplete for many sites. Known and/or suspected population declines at colonies in Baja California and the Channel Islands (USA) and threats from a variety of sources make listing of this species as threatened under the U.S. Endangered Species Act an appropriate course of action.