Session Name: Contributed
Think Pink: Pink Salmon population trends in Puget Sound, WA
Presenter: Dufault, Aaron, M
Contact: aaron.dufault@dfw.wa.gov, 360-902-2791
Dufault, A.M.1, Losee, J.1, Anderson, J.H.1, Jenkins, E.2, Michielsons, C.2, and White, B.2
1: Washington Department of Fish and Wildlife 1111 Washington St SE Olympia, WA 98501
2: Pacific Salmon Commission 1155 Robson St. Vancouver, BC V6E1B Canada
Odd-year Pink Salmon abundances throughout the North Pacific have generally increased in recent
years, but population growth has been particularly dramatic in Puget Sound, WA. Here we present a
long term dataset of Pink Salmon escapement and reconstructed run sizes for odd-year Puget Sound
Pink Salmon stocks from 1959-2013. Using cluster analysis, we found evidence for a range of
spatiotemporal population trends. Puget Sound-wide, Pink Salmon have increased by ~281% on average
over the last 7cycles (2001-13), while individual rivers vary by orders of magnitude. Among rivers that
historically supported robust Pink Salmon populations, the Puyallup R. and Snohomish R. showed some
of the greatest increases, with abundances increasing by ~1844% and 685% respectively (last 7 cycles).
However, in the Green R. where Pink Salmon were not observed until 2001, returns now average ~1
million fish. Spatial coherence in population increases are apparent; rivers within Hood Canal and North
Puget Sound generally group together, both of which have not exhibited the large population increases
present in some of the Central and South Puget Sound rivers. Future research will examine the
mechanistic basis for the spatiotemporal trends in Puget Sound Pink Salmon populations.
Presentation type: Oral Presentation Only