WCVI has several runs of "even year" Pink runs. Not so much on the Fraser system.
Ralph will know the history better than I, that said, I believe the Fraser system even-year Pink run died out as a result of the 1914 Hell's Gate slide.
If you do catch a Pink in the Fraser Valley, carefully release it as seed for an even-year run on this side of the Strait.
AFAIK and have read the south coast, as in south of Courtney has few or even no returns of pinks in even numbered years. The Squamish and the Mamquam in particular has a few. They show up seldom in the Fraser River test catches and at that it may be just 1 or 2. Ralph Wahl, an angler & author in Washing state recorded seeing returns of a few dozen in a backwater of the Skagit he fished decades ago. These disappeared within a decade or so. See his book "One Man's steelhead Shangri La."
No one knows why this is so but best I know even numbered runs were not known in the Fraser at any time in living and recorded memory. Prehistoric slides (such as the Agassiz slide circa 6000 BCE) or the Mount Mazama (Crater Lake) eruption have been offered as causes with little or no supporting evidence.
FWIW from Courtney north pinks tend to have a dominate year (usually the even year) and a sub-dominant year. Some watersheds have fairly strong sub-dominate years other have minor ones or even marginal ones
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