Growth and Population Structure of Georgia Basin Pacific Hake

Two stocks of Pacific hake (Merluccius productus) exist within Georgia Basin (a Puget Sound stock located in US waters and a Strait of Georgia stock located in Canadian waters), but little is known about the extent to which they mix. Given the recent decline in abundances of individuals belonging to the Puget Sound stock (by 85%), quantifying the magnitude of mixing is essential to understanding the scope of the problems faced by this stock. Using archived otoliths corresponding to individuals collected from both stocks across several years (1979-2009) we examined otolith chemical signatures and microstructure in order to assess patterns of stock differentiation and mixing, and somatic growth.