Impact on Oceanographic Changes on Atlantic Salmon Survival in the Northwest Atlantic

Andrew Pershing, University of Maine

The abundance of Atlantic salmon (Salmo salar) stocks in the Gulf of Maine region have
declined over recent decades to all time low levels. The cause or causes of this decline are not
well understood. Human activities (e.g., dams, habitat degradation) are believed to be
responsible for some of this decline. NOAA Fisheries and the University of Maine Sea Grant
program conducted a series of workshops in 2008-2009 that brought together marine scientists
from various disciplines to consider the processes and mechanisms that could have affected
salmon survival during their marine phase. During one of those workshops changes over recent
decades in a number of physical oceanographic characteristics and biological components of the
Gulf of Maine regional ecosystem were presented and documented. The proposed project will
analyze available hydrographic and biological (plankton and fish) time series from the Gulf of
Maine, Scotian Shelf, and Newfoundland region. We will examine correlations between salmon
returns in Maine rivers with oceanographic conditions along their migration route and feeding
areas. We will also contribute to a companion project led by Dr. Jason Stockwell at the Gulf of
Maine Research Institute. We will provide information on circulation variability in the Gulf of
Maine from the Gulf of Maine Princeton Ocean Model hindcasts.