Goal:  To compare the reproductive success of hatchery and wild-origin steelhead spawning naturally in Forks Creek, and the success of hatchery-origin steelhead spawned in the Forks Creek Hatchery.  .

Our past and proposed sampling is designed to take advantage of a special feature of the Forks Creek hatchery operation.  Not only do we sample wild adult steelhead and their progeny as smolts and adults, and sample the adults spawned (or killed as surplus) at the hatchery.  Most importantly, in the first two years when hatchery adults returned (1996 and 1997), the decision was made to allow surplus adults to spawn in the river.  Accordingly, 362 hatchery adults were allowed upriver, along with 59 wild fish, and 117 hatchery fish were spawned at the hatchery in those two years.  However, the decision was then reversed, to deny hatchery fish access to the spawning grounds.  Thus the wild population was exposed to a very strong "pulse" of hatchery influence for two years, followed by an open-ended "recovery" period.  This unusual situation allows us to gather critical data on the extent to which a wild population resists hatchery influence once the influence is largely terminated.

In 2008 we will continue to sample hatchery and wild steelhead adults and smolts.  Given the number of individuals sampled in the past two years we expect to sample about 900 hatchery adults, 100 wild adults and 400 smolts.  The genetic information from these individuals will be added to the database.  Brood year 2006 adults are the grandchildren of brood year 1998 adults; 1998 is the first year after the pulse (see above) of hatchery fish allowed to spawn naturally and serves as a control group.

After laboratory/genetic processing of tissues from sampled fish, parentage analysis will be completed with the goal of quantifying individual reproductive success.  We intend to compare the reproductive success of hatchery fish spawned in the hatchery, hatchery fish spawning naturally and wild fish spawning naturally.

Location:  The study site is at the Forks Creek Hatchery, on Forks Creek just above its confluence with the Willapa River in Pacific County, Washington.