Field Studies of the Interactions of Wild and Hatchery Pink and Chum Salmon in Prince William Sound and Southeast Alaska

Innovative field studies underway for the ADF&G Alaska Hatchery Research Program will meet three objectives: 1) Estimate proportions of hatchery-origin Pink Salmon and Chum Salmon entering Prince William Sound (PWS); 2) Determine extent and annual variability in stream straying of hatchery Pink Salmon in PWS, and Chum Salmon in PWS and Southeast Alaska (SEAK); and 3) Assess relative fitness (productivity) of hatchery strays and wild in natural spawning areas. A subsample of gillnetted salmon from PWS entrances is being examined for presence of otolith thermal marks to estimate hatchery-origin proportions. We also sample spawn-outs in 32 PWS and 32 SEAK natural spawning populations to determine the proportion of hatchery-origin salmon.  We intensively sample otoliths and genetic tissues from spawn-outs in six PWS Pink Salmon and four SEAK Chum Salmon populations to obtain origin and pedigree data to determine the relative reproductive success of hatchery and natural-origin salmon, and their crosses. Data from the PWS ocean and stream sampling will also be used to estimate the total run size of natural and hatchery origin spawners in natural systems in PWS and SEAK.  Preliminary results for 2013 PWS ocean hatchery proportions and PWS and SEAK stray rates will be discussed.