Habitat, hatcheries, and nonnative predators interact to affect juvenile salmon behavior and survival

Start/End: April, 2018 to June, 2020

Resource managers are looking for ways to increase survival of Chinook salmon, which are endangered in the Delta. Factors affecting the survival of the young salmon include predation by non-native predators, as well as the influence of hatchery salmon. Habitat restoration and predator removal are two strategies that could help reduce salmon mortality – but managers need information on the efficacy of both strategies and how they might vary under different conditions.

This study will explore predator prey interactions between hatchery and wild native juvenile salmon and nonnative bass on the Lower Mokelumne River. The specific objectives are to:

  1. Examine how habitat structure, salmon attributes, and origin (hatchery vs. wild) influence predation rates by striped bass and salmon movement behavior.
  2. Develop a predation model to assess increases in salmon survival under different management scenarios on the Lower Mokelumne River.

This model will allow researchers to run scenarios with different management options to compare the potential impacts on salmon survival and allow managers to design restorations strategies that fit best for specific locations and stakeholders.

Research Mentor: Eric Palkovacs, University of California Santa Cruz
Community Mentor: Steve Lindley, NOAA Southwest Fisheries Science Center

  • University of California, Santa Cruz (UCSC)