January Floods Hurt Northwest Salmon
January 21, 2012
As a lover of steelhead and salmon, I have mixed emotions about high water. Sure, I hate to miss a fishing day because the rivers are blown, but I relish the thought of all those chrome fish slipping high into the spawning grounds without encountering a single angler. But high water in January--or rather flood water in January--is a whole different affair.
Within the gravel at this very moment are millions of fertilized salmon eggs. In my neck of the coast, most every chinook has spawned by now, and nearly all coho have spawned too. And flood waters like the Northwest is seeing now displace that gravel, disrupting the eggs. But maybe most lethal is all the silt that washes free from clear cuts and logging roads and fans out over the gravel, effectively smothering the fish where they incubate.
I talked to my local District Biologist yesterday about this very event, and he guessed that this generation of chinook would likely be devastated. He suspected those coho eggs in the gravel would be wiped out too, but that the few remaining coho would likely make up for the loss. That's because when they reach the spawning grounds, they'll find fresh new gravel, the result of new erosion and general displacement from farther upstream.
And therein lies the silver lining for salmon during a January flood: the high water and violent currents help reinvigorate the river with not only new gravel but also new woody debris, which is an essential component of rearing habitat, both for the holding water and new bug life it creates. The salmon will have trouble in the short term, but in the long term, they may find a healthier river in the flood's wake. And a healthy river leads to healthy fish, eventually.