From Herpetological Review 33(2). pp 120-160:

BUFO CALIFORNICUS (California Arroyo Toad). HABITAT and POPULATION STATUS. In the coastal and foothill drainages of southern California and northwestern Baja California, Mexico, populations of the endangered Bufo califorincus are often associated with open to partially open stream terraces, shallow permanent or intermittent streams and pools, and sand and gravel stream bottoms free of vegetation from periodic flooding (McLaughlin and Stephenson 2001. Fed. Register 66[26]:9414-9474). Although several authors have studied the species’ ecology in coastal drainages and, to a lesser extent, in upland habitats of southern California, reports on the natural history, distribution, and status of B. californicus in Baja California are lacking (U.S. Fish and Wildlife Service 1999. Arroyo southwestern toad (Bufo microscaphus californicus) Recovery Plan. USFWS, Portland, Oregon. 119 pp.). Currently, B. californicus is distributed disjunctly in northwestern Baja California from the coastal plains (e.g., Rio San Vicente, Rio San Telmo, Rio Santo Domingo), inland foothills (e.g., Cation Agua Caliente, Ojos Negros, Rio Valladores,Rancho San Antonio, Arroyo San Rafael), peninsular range of the Sierra San Pedro Martir (e.g., Mision San Pedro Martir, La Grulla at 2157 m, Santo Tomas), and south to Arroyo Simon, ca. 16 km southeast of San Quintin (Gergus et al. 1997. Herpetol. Rev. 28:47).