Restoring Thermal Refugia for Coho Salmon in the Mid-Klamath

Mid Klamath Creek Mouth and Off-Channel Enhancement Project

This project is being led by the Mid-Klamath Watershed Council and implemented a survey of creek mouths of tributaries that flow into the Mid-Klamath River. The project was conducted through partnerships with tribal agencies, local landowners and area residents.

The primary project goal was to identify and prioritize restoration projects at creek mouths, which allow coho salmon to access cold water "thermal refugia" within the creeks. These refugia are often pools and low gradient stream segments within flood plain areas around creek mouths of creeks. They are important during low flow summer months, when the mainstem Klamath temperature can become lethal for salmon.
Recent infrared images show the temperature differences between the mainstem. Many of the creek mouth restorations have recently been implemented, and involve a wide range of interventions -- ranging from building step pools, to removing blocked culverts, to redirecting creek flows.

Several interesting elements of these projects are 1) prioritization, 2) the role of historic conditions, and 3) implications of funding limitations, 4) community involvement, and 5) monitoring. What stands out in this project is the broad range of partnerships that allow for extensive fish monitoring and stream temperature measurements to take place, with community volunteers. Photo point monitoring and snorkeling surveys at the creek mouths is a main monitoring strategy.
The funding limitations however, require the organization to carefully prioritize creek restoration projects, through a) evaluating the physical barriers for fish to reach refugia, because creek sites are all different and require different interventions, and b) comparing the abundance of coho currently found in the region.
Historical aerial photos provide a useful record of historic conditions that enhanced cold water creeks, and highlight the issue of changes over time in the creek beds. Some creek beds have changed drastically, as a result of drastic human intervention in the system from road building and mining. In some cases, landslides have caused creeks to shift out of old creek beds into a new drainage channel. What does this mean for restoration?

In some cases, restoration groups would prefer a restoration project that addresses changes in creek hydrology at a fundamental level, but these large-scale changes are expensive and political. Instead, what is feasible is only the band-aid solution -- providing a mini-refugia. This brings up the scale issue. Restoration managers bring up the issue of whether the spacing of the refugia is adequate and would like to do more, but potential for landscape scale restoration is only just now becoming a possibility with the Klamath Restoration Settlement.

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