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LETTER: Friends of Kootenay Lake should read the science

From Harvey Andrusak, former provincial director of fisheries

The Friends of Kootenay Lake Stewardship Society (FoKLSS) project to assist restoration of West Arm shore spawning kokanee is laudable but unfortunately ill-conceived.

I conducted the original research on this population decades ago as well as recently. These shore spawners are only found where there is upwelling ground water at stream mouths at Six Mile, Harrop and Sitkum creeks. Monitoring seepage and water temperature is proposed, but these measures should occur before any gravel placement. Simply dumping gravel at a lower elevation level is hardly good science. Research on Alouette Reservoir deep water spawning should be read by FoKLSS before advancing their project.

The FoKLSS incorrectly assumes that spawning habitat is currently limiting kokanee shore spawners and that more gravel equates to more kokanee. This idealistic notion fails to acknowledge the real reason why West Arm kokanee abundance is so limited. The inconvenient truth is that lake level regulation limits kokanee food, hence abundance not spawning habitat. Producing more kokanee via restoration of shore spawning habitat will not produce more kokanee. Why?

Kokanee fry produced by two spawning channels are limited by rearing habitat associated with the shoreline. When fry enter the lake in springtime they stay onshore relying on shoreline food. Of course the springtime shoreline today looks like a desert due to the lengthy, legal drawdown. Annual production of one-to-two million fry from the spawning channels only results in 10-20,000 spawners. This means less than two per cent survival from fry to adult compared to four-to-five per cent prior to operation of the Libby Dam. The power companies are more than happy to fund shore spawning restoration efforts because this avoids the real solution of stabilizing the lake level at something less than status quo that currently maximizes power production.

My intention is not to simply criticize FoKLLS but rather inform that a) there is science that should be read and not ignored and b) problems and solutions for West Arm kokanee are far more complex than conveyed in your Sept. 10 article.

Harvey Andrusak

Former Kootenay Lake fisheries biologist

and provincial director of fisheries

Nelson Star

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