In November and December, the Chinook or King Salmon make their run into rivers along the Pacific Coast to spawn. Here, in Sacramento, they spawn in the American River. They lay their eggs in gravelly nests in shallow river beds. They need clean, cool, oxygenated, sediment-free fresh water for their eggs to develop. That means water that runs freely. Visiting Effie Yeaw Nature center yesterday, I got to watch some of the salmon preparing nests.They swam around in tight circles contorting their bodies and swishing their tail fins to clean any sediment from an area of river gravel. When they are done, the females will lay their eggs and the males will fertilize them. When finished spawning, both the males and females die. After the eggs hatch, those that survive mature for a few months then find their way to the ocean. If you walk along a river where salmon breed, look for an area where rocks are clean and shiny – it may be a salmon nest. They are usually about 6 feet by 2 feet.
I learned recently that prior to damming the American River,the salmon had a spawning ground of over 100 miles in the main river and tributaries. After the damming, it was reduced to 8 miles. To compensate, there is a fish hatchery just downstream from the Nimbus Dam. They open the fish ladders in November and December to capture salmon and spawn them. When the eggs hatch and grow to about 40 salmon per pound, they are released. They tag these salmon in some way and have tracked a 5 in 1000 success rate in salmon returning to breed. After the salmon run, they catch and spawn steelhead. The steelhead naturally come upstream to dine on salmon eggs.
In California, allocation of water is a contentious issue.Farmers have been promised water for irrigation and have seen those promises go unfulfilled, especially in years of drought. One of the oft sited points of contention is the amount of water required to support fisheries. As I pointed out above, the salmon need clear, cool, fresh water for their eggs to develop.Water that is kept in dams gets warmer and of course the outflow into the river is smaller. In order to protect the salmon fisheries, not just for human consumption, but also to keep the food chain enabled, some of the water needs to keep flowing from the dams. Many people rely on the fishing industry for their livelihood; not just for recreation. There are many other factors to consider. But, for this portion of the discussion, we must ask ourselves if the lettuce, almonds or beef are more important than the salmon to our diet because this is one of the compromises that need to be worked out.
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