Integrative Research for Assessing the Impacts of Climate Change on Pacific Salmon (Oncorhynchus spp.)

Effective conservation and management of natural resources requires accurate predictions of ecosystem responses to future climate change. The future response of Pacific salmon (Oncorhynchus spp.) to a changing environment and continued anthropogenic disturbance is of particular interest to the public because these fish have very high economic, social, and cultural value. Additionally, their anadromous life history exposes salmon to a wide variety of freshwater, estuarine, and marine habitats, each of which will respond differently to a changing climate. In the Pacific Northwest, collections of similar salmon populations have been grouped into Evolutionarily Significant Units (ESU) for purposes of management. Over 50% of these ESUs are currently listed as threatened or endangered under the U.S. Endangered Species Act. Developing effective recovery options requires us to address the broad spectrum of interacting factors that influence the viability of Pacific salmon. This presentation will highlight a diversity of research approaches, completed and currently underway, that explore the potential responses of salmon to directional change and variation in future climate across the Pacific Northwest. We begin by combining information from empirical studies and statistical analyses into life-cycle models that allow us to map natural and human effects onto changes in growth, survival, etc. We then develop scenarios of future changes to aspects of various aquatic environments based on future projections from global circulation models and hydrology models (e.g., temperature, river flows) as well as retrospective analyses of climate variability (e.g., El Niño/La Niña; Pacific Decadal Oscillation). We can then ask questions relevant to planning such as, what will climate change do here? Will planned actions be effective in lieu of it? If not, what could be done to accommodate change?