What is a Spawning Channel?
Artificial spawning channels are built adjacent to salmon
rivers, directing a controlled flow of water over extensive
gravel spawning beds. The rate of flow and water depth is
set to create ideal spawning conditions.
Salmon spawn naturally in spawning channels.
Studies have shown that egg-to-fry survival rates can
increase 10 fold in spawning channels as compared to
survival in the adjacent, natural stream.
The serpentine channels are not exposed to the seasonal
floods that can wash away and kill salmon eggs in the
natural river. But without floods to flush the gravel
clean, sediment builds up eventually smothering the
spawning beds.
Spawning channels have to be cleaned every few years by
crews that use heavy equipment to scoop up dirty gravel and
"cast" it over the bottom, dislodging sediment, which is
washed away. Dirty water created in the cleaning process is
pumped away from the channels so as not to settle farther
downstream.
Spawning channels attract bears during the fall, because
the salmon are easily caught in the shallow waters and
steady currents. That phenomenon has led to the creation of
bear tourism businesses in B.C. and most spawning channels
now have bear viewing platforms on them.
Source from : Wild BC Salmon
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