The Case for Prioritizing West Marin as a Beaver Relocation Site

Adam Rivers

The California Department of Fish and Wildlife (CDFW) Beaver Restoration Program (BRP) must allocate a limited number of translocations across many candidate watersheds. This paper argues that West Marin, the coastal watershed anchored by Lagunitas Creek, warrants placement in the top tier of the CDFW's prioritization model. West Marin is the rare site that is at once highest-value, lowest-risk, mission-central, cost-effective, grounded in documented native range, and coalition-ready. It holds the southernmost wild population of Coho Salmon on Earth, an irreplaceable evolutionarily significant unit. Its low-elevation coastal setting structurally lacks the apex-predator pressure that drove mortality in CDFW's first-year pilots. It delivers the quantified climate, drought, and wildfire benefits that are the BRP’s founding mandate. Beaver-built habitat there substitutes for the engineered restoration on which the local water utility has already spent millions of dollars. Pre-contact beaver presence on the Marin coast is established by physical and archival evidence rather than assumed. Its coalition is already in place: a private landowner, the regional water utility, federal land managers, and restoration nonprofits, with letters of support on file. The following sections quantify each of these claims against the Department's own pilot data and the published restoration literature.