Population Trends

Dramatic Decline Beginning in 1970s

Over the past two centuries, river herring populations have drastically decreased. Historically, alewife and blueback herring were extraordinarily abundant in the rivers, estuaries, and ocean waters of the eastern United States. They inhabited seemingly every stream and river from South Carolina northward to Canada. Total commercial landings of river herring in Atlantic coastal states peaked from 1950 through 1970, averaging more than 50 million pounds per year.

More recently, however, annual landings have averaged only approximately one million pounds — 98 percent less than the peak landings. Many rivers and streams that previously teemed with alewives and blueback herring now have very few, and in some places the populations have been lost entirely.

2012 Stock Assessment Revealed Sharp Drops

The Atlantic States Marine Fisheries Commission (ASFMC) in 2012 completed a comprehensive, detailed stock assessment of alewife and blueback herring. Based on several indicators of stock status, ASFMC determined that of the 52 stocks of alewife and blueback herring for which data were available, 23 were depleted relative to historic levels, one stock was increasing, and the status of 28 stocks could not be determined because the time-series of available data was too short. ASFMC defined the stocks as “depleted” instead of “overfished” because many factors apart from fishing have contributed to the decline in river herring, including habitat loss, predation, and climate change. Because the assessment had been hampered by insufficient data, ASMFC identified high priorities for data collection, which the states are now pursuing through their monitoring programs.