Climate Change Threats to Fish Habitat Connectivity

Start Date

2010

End Date

2012

Release Date

2011

An interdisciplinary U.S. Geological Survey (USGS) team worked with local stakeholders in the Methow River (a tributary of the Columbia River) in arid eastern Washington State to develop decision support tools with which to evaluate possible climate change effects on natural resources, human economies, and Native American cultural values. A stakeholders’ workshop was held, which was attended by local politicians; federal, state and NGO resource managers; ranchers and farmers; and Tribal representatives. Products from the workshop included stakeholder-defined goals for adapting to climate change. An important aspect of adaptation of aquatic resources in the Methow Basin is the role of habitat connectivity on the ability of native fishes to obtain food. Native fishes participate in feeding both as predators and as prey. With funds from the Great Northern Landscape Conservation Cooperative and the Northwest Climate Science Center (NW CSC), we examined the influence of temperature, habitat availability, and flow under normal conditions and under climate change scenarios to simulate growth and consumption by fish and estimate the potential impact of predation on juvenile ESA-listed salmon. Specific tasks included: (1) determining if large bodied fish (bull trout, cutthroat trout, and mountain whitefish) feeding in the mainstem Columbia River experience increased growth, which increases their predation on juvenile salmon in the Methow River; (2) developing parameters for bioenergetics models for bull trout and mountain whitefish to predict their growth under predicted climate change scenarios; and (3) determining current and potentially available side-channel connectivity, which provides rearing areas and refugia from predation for juvenile fish, in the mainstem Methow River. With NW CSC funds we modeled possible effects of climate change on fish habitat by completing the side channel assessment and combining that with existing tributary and mainstem models that predict flow under several climate change scenarios. These predicted changes will be run through an existing fish habitat decision support system to predict changes in habitat.

ScienceBase WMS

• LC MAP - Landscape Conservation Management and Analysis Portal
• National and Regional Climate Adaptation Science Centers
• North Pacific Landscape Conservation Cooperative
• Northwest CASC