Life-cycle monitoring stations collect data on anadromous juvenile fish traveling downstream and adult fish traveling back upstream on the same river, thereby surveying a population at multiple times during the fish life cycle. Designing these stations to monitor salmonids can be particularly challenging on coastal streams, due to the highly variable environmental conditions of these waterways, as well as the migration characteristics of coastal salmon and steelhead. FISHBIO partnered with the Resource Conservation District of Santa Cruz and the National Marine Fisheries Service (NMFS) to develop a decision matrix tool for identifying the most suitable salmonid life-cycle monitoring station techniques to use at a given site. This tool compares a range of potential survey techniques (everything from stationary fish traps to hydroacoustic technology) that vary considerably in their complexity and cost. We focused on Santa Cruz County’s Scott Creek as a case study for the development of the tool, but the decision matrix can be applied to other coastal streams with coho salmon and steelhead. The California Department of Fish and Wildlife (CDFW) Fisheries Restoration Grant Program funded the creation of the Microsoft Excel-based decision matrix, which is available to download along with a final report. The report outlines how to use the matrix and provides examples based on the Scott Creek case study.
There are many techniques available for salmonid life-cycle monitoring, and selecting the most appropriate techniques for a study can be somewhat subjective and context dependent. The matrix helps streamline the methodology decision-making process based on site-specific environmental parameters (such as channel depth, water velocity, turbidity, and substrate mobility), and other considerations such as cost, equipment portability, and lead time. For example, the highly variable flows in Scott Creek can mobilize relatively large, lightweight cobble during salmonid migration periods, which limits the types of equipment that can be used during these crucial monitoring timeframes. Researchers can use the criteria in the decision matrix to objectively and quantitatively compare alternative techniques, rank them based on their appropriateness, and thus choose the method that is best suited to their study site. By allowing researchers and fisheries managers to identify the best scientific methods available for their specific circumstances, this tool will help improve the collection of data required for long-term salmonid population modeling.
Download the Life-Cycle Monitoring Decision Matrix (Excel file)
Download the final Life-Cycle Monitoring Decision Matrix report (pdf)