Helping Trout and Salmon Survive Climate Change
The effects of a rapidly changing climate will further stress habitats and populations that already have been pushed to their limits by water extraction, land use changes, increased road density, and impacts from non-native fishes. Fortunately, trout and salmon are resilient. They have adapted to many fluctuations in climate and environmental conditions during their long evolutionary history. As the last glaciers melted in North America over 10,000 years ago, these fish were able to migrate to the rivers and streams where they now live. Lakes formed and dried up, rivers expanded and contracted, and trout and salmon always found the cold water habitat they have needed to survive.
To help trout and salmon survive the effects of global warming, there needs to be an active and integrated effort to protect the best remaining fish habitats and populations, to reconnect fish habitats by removing instream barriers and reestablishing instream flows, and to restore vital main-stem river and streamside habitats. Finally, significant efforts must be made to sustain restoration on the ground by engaging local communities, state and federal agencies, conservation organizations, landowners, and industry groups in the recovery of the lands and waters where trout and salmon thrive.
By working collaboratively at a landscape scale on a focused effort to protect, reconnect, and restore fisheries and fish habitat, we can increase resistance and resilience to climate change and insure a future with healthy aquatic systems. In order to strengthen the resistance and resilience of trout, the following steps must be taken:
1. Protect Remaining Critical Habitat Areas. It is vital that remaining rivers and streams where salmon and trout live are protected. Well-protected headwater streams and lakes that provide high quality, cold water flows will be integral to maintaining suitable downstream conditions during periods of warming. Key watersheds that are roadless or otherwise minimally disturbed typically provide the most reliable sources of cold water.
2. Reconnect High Quality Habitats. Identify and reconnect important stream systems that have been physically disconnected by dams and culverts or that seasonally run dry from water diversions and other dewatering processes.
Trout and salmon need to be able to access a wide variety of habitats, from small headwater streams to deep river pools. These waterways are most valuable when they are connected to one another. Barriers that restrict fish from moving up and down the watershed can reduce overall fish populations and compromise their genetic integrity.
3. Restore Entire Watersheds, Not Just Individual Streams and Rivers. Taking a broad geographical approach to identifying areas to improve water quality, streamside vegetation and instream habitat is critical to restoring the overall health of lower elevation, valley bottom streams and rivers. By restoring streams and floodplains to a healthy, more natural state, fish will be better able to withstand the impacts of rising temperatures, floods, fires, and droughts.
4. Sustain Conservation and Recovery Efforts. In little more than a single generation, we have moved from a rural existence to life in sprawling suburbs and cities. This lifestyle change has diminished our connection to nature. Our youth has been most affected as electronics have largely replaced the outdoors as a source of enjoyment, resulting in what has become known as "nature deficit disorder." Climate change provides an important reminder that our society is still dependent on the health of our natural environment.