Cooperative Fish and Wildlife Research Units Program: California
Education, Research and Technical Assistance for Managing Our Natural Resources

The core objective of the tidewater goby recovery plan is the development of standardized survey methods for population monitoring. We propose assessing the potential of using environmental DNA in water samples as a tool for monitoring the endangered tidewater goby in lagoon and bay habitats. Environmental DNA is a cost-effective and noninvasive technique that has been successfully applied to a broad range of taxonomic groups, including fish. Studies have shown that environmental DNA can closely track presence/absence and can be useful for monitoring species that cannot be detected using conventional field approaches. Despite apparent promise insufficient testing has been conducted to determine the suitability of environmental DNA approaches for monitoring tidewater goby. We propose experiments in controlled conditions to assess the suitability of environmental DNA techniques for tidewater goby presence/absence detection. The future goal is to incorporate environmental DNA into site occupancy modeling design to allow robust monitoring of tidewater goby. This approach has the advantage of costing a fraction of field surveys, eliminates issues thwarting field studied (permits, landowner access, and inaccessibility due to weather), and could be used to monitor tidewater in coastal habitats throughout California.