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In the Nechako, the white sturgeon population has dropped from what some scientists believe was a minimum of 5000 fish to less than 500. And the vast majority of those fish are more than 30 years old. Available population estimates for upper Columbia River white sturgeon have ranged between 900 and 1,400 wild fish in the Canadian portion of the basin and 1,500 to 2,000 fish from the Canada-U.S. border to the Grand Coulee Dam in the U.S. Like the Nechako population, almost all fish are greater than 30 years old, suggesting that sturgeon are either not reproducing successfully or that the young are not surviving to adulthood. As sturgeon do not begin spawning until they are 15 to 30 years old, the lack of young sturgeon in the Nechako and Upper Columbia means that an entire generation is already missing. In the Fraser the population is much larger (an estimated 62,000 animals), however, negative changes to habitat, increasing water pollution and changing water temperatures could continue to negatively impact this population.
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