PIT Tag Adult Detection Probability at Adult Fishways

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) = $\sqrt{\mathrm{rz\; /\; (r+z)³}}$