Monterey County Steelhead Monitoring Project FY24/25

From June 2024 to May 2025, California Department of Fish and Wildlife staff monitored steelhead trout (Oncorhynchus mykiss) within the Big Sur Coast Biogeographical Population Group management area. The monitoring that occurred as part of the California Monitoring Plan (CMP) for Region Four, Monterey County, was divided into two phases. The first was the winter adult steelhead monitoring on the Big Sur River. The second aspect was the juvenile steelhead trout electrofishing and snorkeling surveys spread over the entire Big Sur Coast Biogeographical Population Group management area.

Anadromous O. mykiss populations along the Big Sur Coast range are part of the federally threatened South-Central California Distinct Population Segment. According to the National Marine Fisheries Services South-Central California Coast Steelhead Recovery Plan (Recovery Plan), steelhead populations have been negatively affected by anthropogenic activities including construction of barriers to fish migration, diversion of surface- and ground-water flows, and agricultural and urban development (NMFS 2013). In collaboration with NMFS, the California Department of Fish and Wildlife (CDFW) is developing anadromous Salmonid population survey methodology to better understanding of population status and trends. These watersheds once sustained large and healthy anadromous O. mykiss populations. The Recovery Plan describes that obtaining anadromous O. mykiss population data for these systems is a crucial component of adopting appropriate management strategies (NMFS 2013).