Lower Columbia Subpopulation Status and Trends
Information and data adapted from Parker, B., T, Rien, B. James, R. Beamesderfer.
2013. Review Draft Columbia Basin White Sturgeon Planning Framework. Portland, Or.
To view all subpopulations in the basin
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Of the 26 white sturgeon subpopulations, the Lower Columbia subpopulation is the
most abundant and productive and is considered by managers and researchers as healthy
and currently not at risk, despite declining since 1995. In 2011, managers estimated
an abundance of 72,700 white sturgeon (42-60 inches) downstream from Bonneville
Dam to the mouth of the Columbia River.
Monitoring results indicate that survival of juvenile white sturgeon through their
first year of life (i.e., recruitment) was lower in 2010 than any of the six previous
years and was significantly lower than the 5-year average. The 2010 results are
concerning since recent declines have been observed relative to the abundance of
white sturgeon that are characterized as “legal” (42-48 inches).
As white sturgeon abundance has continued to decline, managers have been required
to modify regulations to limit harvest. In 2011, a total of 14,500 fish were harvested
(sport and commercial), significantly less than the 10-year average of 37,869 and
about 4,000 fewer than were harvested in 2010. It is anticipated that beginning
in 2014, there will be a closure of white sturgeon retention seasons in the Columbia
River below Bonneville Dam.
Abundance
* Abundance was not estimated for 1994 and
2004.
Density
Not estimated.
Productivity
* Monitoring did not occur during 2007.
* For a description of the methods used to estimate the index value that is associated
with the number of fish that survive during their first year , please visit
Monitoring Method website.
Hatchery Releases
No releases
Harvest