[8] However stream resident coastal rainbow trout, run up from Searsville Reservoir to spawn in upper Corte Madera Creek and its tributaries, enabling this native fish to survive above the dam as well.

[13] Leidy concluded that coho salmon were likely present and cited that the most suitable habitat for coho salmon was in perennial, well shaded reaches of mainstem San Francisquito Creek, and several small, perennial tributaries including Los Trancos, Corte Madera, Bear, and West Union creeks.

[14] In addition, three independent oral history sources indicate that coho salmon were abundant in the creek through the first half of the twentieth century.

[4] A second source described catching "steelhead and silver (coho) salmon in San Francisquito Creek and the Guadalupe River System in the 1930s and 1940s.

"[16] Thirdly, Dennis L. Bark, a senior fellow at the Hoover Institution, recalls playing on San Francisquito Creek around 1947: "Salmon swam up it, and in winter it was a dangerous place.

[18] Also, the southern limit of Coho salmon in coastal California streams was recently confirmed to extend through Santa Cruz County based on both archaeological evidence and historically collected specimens.

[19] In a 1996 biotic assessment of Searsville Reservoir and the lower floodplain of Corte Madera Creek, Stanford biologists wrote that the native species likely included coastal rainbow trout (Oncorhynchus mykiss irideus), sculpin, California roach (Hesperoleucas symmetricus), hitch (Lavinia exilcauda), speckled dace (Rhinichthys osculus), Sacramento sucker (Catostomus occidentalis), Pacific lamprey (Entosphenus tridentatus), and perhaps three-spined stickleback (Gasterosteus aculeatus), Sacramento pikeminnow (Ptychocheilus grandis), Sacramento blackfish (Orthodon microlepidontus), and coho salmon (Oncorhynchus kisutch).

They noted that federally threatened California red-legged frogs (Rana draytonii) occur in the lotic portions of Corte Madera Creek below the dam but not above, likely due to depredation by non-native fish and American bullfrogs (Lithobates catesbeianus).

Native species found when the plunge pool was pumped dry include two steelhead trout, 26 California roach and 22 Sacramento suckers.

A 2007 study by the Jasper Ridge Advisory Committee describes five main options The Center for Ecosystem Management and Restoration (CEMAR) has issued comments on Stanford University's April 2010 document, "Draft Environmental Impact Statement for Authorization for Incidental Take and Implementation of the Stanford University Habitat Conservation Plan" (HCP DEIS), finding that because the Searsville Dam project involves water diversion, bypass flows, and potentially major and ongoing dredging for 50 years, that the impacts of operating the diversion dam must be analyzed in the HCP EIS.

Anti-dam proponents point to a growing trend in habitat restoration nationally with over 500 dams removed in recent years.