Thoughts about the Stock Concept as Applied to Fisheries Management in the Great Lakes

The purpose of this paper is to summarize how the stock concept has influenced fishery management in the Great Lakes.  Fishery managers first became concerned about the status of fish populations in the late 1800s as populations of lake sturgeon and Atlantic salmon declined.  Between the 1920s and 1950s, many Great Lakes fish populations crashed due to overfishing and effects of invasive species.  Also during that period, substantial investments were placed into fisheries research and management of the Great Lakes.  By the 1960s, fishery management agencies began stocking native lake trout and Pacific salmon to rehabilitate fisheries and restore ecosystem function.  During this process, the use of several lake trout strains played an important role in fishery management decisions, a role that continues to the present.  Advances in genetic techniques and concerns about introgression led to improved husbandry and spawning practices in the 1990s, further conserving genetic material for reintroduced fish.  As increased information about genetics of Great Lakes fish stocks has become available, managers must incorporate both positive and negative aspects of genetic information.  Current management practices and genetic research combine to provide the most robust information for managers who seek to maintain fish stocks as reintroduction efforts, recreational and sport fisheries, and societal desires for diverse fish populations interact to shape fishery management programs in the Great Lakes.