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Living With the Methow River Monthly Activities and Learning Opportunities November 2017 Fish Barrier Surveys Migrating adult salmon are famous for their ability to leap and swim up waterfalls to reach their spawning grounds, but they can only jump so high. Human-made barriers such as dams and poorly-placed culverts can impede fish passage, often preventing fish from reaching important habitat. A fish barrier survey looks at the river from a fish's perspective. How high do they have to jump? How long a pipe do they have to swim up before they reach a pool? A poorly placed culvert or irrigation dam may lock fish out of miles of otherwise available habitat. Identifying these barriers is the first step to restoring access. Removal of a single fish barrier can open up side channels, ponds, even an entire creek to migrating salmon and steelhead. A habitat restoration project can restore habitat within the project site; removing a fish barrier can restore fish to existing habitat far beyond the edges of the work site. Removal of fish barriers can be as dramatic as removing a dam or as simple as replacing a culvert (which often sit too high or flow too fast to allow fish passage) with a small bridge, which allows the steam to pass underneath uninterrupted. Replacing culverts is also beneficial in preventing washouts and flooding, as the culverts that block fish also tend to clog with flood debris. This kind of project has been done locally along Frazer Creek, where a project by the Methow Salmon Recovery Foundation replaced a series of culverts washed out by post-fire flooding with bridges, restoring landowner access while also easing fish passage through the creek. For more about removal of fish barriers in Washington State, click here.
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This year’s MRC calendar connects to ADVENTURES, ACTIVITIES AND INFORMATION tailored to each month. If you haven't gotten your calendar yet, you can download an electronic version here. Come back each month and find interactive activities, print outs, and suggested learning opportunities in our community.
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