Annually, DART generates detection probabilities for three juvenile release regions for Chinook, Coho, Steelhead, and Sockeye detected as adult at Bonneville Adult Fishway Ladders.

1. Detection Probability at a Given Project for a Specific Year = $$r / (r + z)
   where:
   r is the total number of fish detected within a specific year from a given release, R, at a given project, e.g., McNary, and at any location upstream of the project after the detection at the given project
   z is number of detected fish within a specific year at any location upstream of the given project from a given release, R, not detected at the given project
   R is virtual release of fish detected at Bonneville Dam Adult Fishways within a specific year meeting the release basin, species, run and rear type criteria.
2. Standard Error is calculated using the Manly-Parr estimate of detection probability
   SÊ(p̂) = $\sqrt{\mathrm{rz\; /\; (r+z)³}}$