If I remember correctly they take 6,000 of each sex from a crossection of the run for broodstock and release about 17,000,000 unfed fry into the Cedar River annually.

The hatchery return is somewhere around 25% of the total return on the better years.

The hatchery fish are heat marked on their ear bone enabling the bio's to determine the composition of the run but not until after a crossection of fish killed for examination.

You can find the hatchery management plan on the WDFW website.