Estimating the Abundance and Distribution of Green Sturgeon Using a DIDSON Acoustic Camera

We compared using a Schnabel method mark-recapture design to a plot sampling estimation method to estimate the abundance and distribution of adult Green Sturgeon in the Rogue River.  The Schnabel method used a 30m x 10m x 10inch stretch, gill nets deployed in the Rogue River during the fall of 2007. This sampling resulted in 76 individuals captured and nine repeated captures. Concurrently known aggregation sites were searched with a DIDSON acoustic camera to record fish densities. The technique of plot sampling produced superior confidence intervals with a more efficient allocation of effort. The Rogue River was surveyed in 2007 and 2010 to estimate the abundance and distribution of adult green sturgeon during their spawning period. We will provide a comparison of the two abundance estimates and discuss the distribution of in river Green Sturgeon.