Stillaguamish Tribe zis a ba restoration effectiveness monitoring

This award completed pre-project effectiveness monitoring of a tidal wetland restoration project at a tribally owned property (known as zis a ba) in the Stillaguamish estuary. Although this project was originally scoped for post-project monitoring, we were unable to secure a second year of pre-project monitoring funds and used these monies to complete the pre-project data collection instead. More than one year of pre-project data is needed to evaluate post-project effects since juvenile salmon use of the Stillaguamish estuary is highly variable

For this project, a field crew sampled marshes in and around zis a ba twice a month during the late winter, spring and early summer months for two years, pre-project. Fish were captured using both fine mesh (1/8”) seines and fyke nets (depending on the exact site), identified to species, enumerated and released. Captured Chinook marked with coded wire tags (hatchery fish) were lethally sampled to determine origin, and wild Chinook had a fin clip removed for genetic analysis (genetic analysis funded with separate grant). Environmental data (water temperature, salinity, pH, and turbidity) was collected from the sampling locations. All data was entered into a database and genetic samples run.

Once the post-project monitoring is completed (est. 2021) a report will be generated evaluating the project’s benefit to listed Chinook salmon populations. Monitoring work at zis a ba is designed to measure salmonid use of the restored marshes at zis a ba and compare to nearby reference sites. Significant deviations from expected fish densities could indicate that adaptive management action is warranted at the site to improve fish use. Successfully restoring tidal marsh habitat in the Stillaguamish is a key component of the NOAA approved Puget Sound Chinook ESU recovery plan, and it is important to monitor and learn from recently completed tidal restoration projects.

The goal of the project is to measure salmonid use of the restored marshes at zis a ba and compare to nearby reference sites. Significant deviations from expected fish densities could indicate that adaptive management action is warranted at the site to improve fish use. Successfully restoring tidal marsh habitat in the Stillaguamish is a key component of the NOAA approved Puget Sound Chinook ESU recovery plan, and it is important to monitor and learn from recently completed tidal restoration projects.