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John Day 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 click here
The abundance and density of white sturgeon in the John Day Reservoir have remained relatively constant since 2004. In 2010 and 2004, abundance estimates for white sturgeon (>24 inches) were 40,649 and 43,500, respectively. Density estimates were 0.8 white sturgeon/acre in 2010 and 2004.

Monitoring results indicate that survival of juvenile white sturgeon through their first year of life (i.e., recruitment) occurs less than 50% of the time in the John Day Reservoir. From 2000-2008, survival of juveniles through their first year was not observed. Monitoring data from 2004 illustrates a lack of recruitment of individuals into the >24 inch size category, reflecting the initial lack of juvenile survival that was observed in 2000. From 2004 through 2010, the number of fish at the lower end of the >24 inch size category continued to decline. The lack of juvenile survival has resulted in a white sturgeon population that is comprised of a relatively low abundance of larger fish. Recruitment index values in 2011 were significantly higher than the five-year range and were the highest recorded for John Day Reservoir since 1999.

Occasional recruitment of fish beyond their first year coupled with conservative harvest regulations have resulted in the subpopulation being characterized by managers as stable. Subsequently, this population provides, through catch quotas, limited commercial and recreational harvest opportunities. In 2010, managers estimated that 4,350 fish were within the harvestable size range. During 2012, the combined annual catch estimate for the John Day commercial and recreational fisheries was 1,818, which was significantly more than the 10-year average of 303 fish.

Abundance



* Monitoring did not occur during years for which data do not exist.








Density




* Monitoring did not occur during years for which data do not exist.

Productivity


* Index value 0 = No recruitment during that year
* 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





See other data snapshots that help us gauge the abundance of fish and wildlife:

Subpopulations for Lower Mid-Columbia Management Unit

Other Management Units - Subpopulations