Mystic River Herring Run Estimated at 198,932

For the first time since the Civil War, river herring (both Alewife and Blueback herring) made their way to the Upper Mystic Lake on their own. Using the newly renovated Massachusetts Department of Conservation and Recreation’s Mystic Lakes Dam, which now includes a fish ladder, these fish traveled from the Atlantic Ocean to some of the most desirable spawning habitat in the Mystic River Watershed – the Upper Mystic Lake in Medford, Arlington and Winchester. And their epic journey did not go unnoticed. For twelve weeks volunteers with the Mystic River Watershed Association’s newly established Herring Monitoring Program counted herring at the fish ladder twelve times every day. All told, 21,052 herring were counted passing through the fish ladder thanks to the steadfast efforts of over 85 volunteer fish monitors, logging 685 total observations. 

Using Massachusetts Division of Marine Fisheries software, Mystic River Watershed Association (MyRWA) staff scientists estimate that 198,932 +/- 18,062 herring migrated to the Upper Mystic Lake this spring. This data represents an important baseline determining critical herring trends in the Mystic River Watershed and allows us to learn more about herring habitat conditions.  In addition to the Herring Monitoring Program, the Mystic River Watershed Association also performs herring habitat assessments of Mystic River, Alewife Brook, Little River and Little Pond.

Katrina Sukola, Watershed Scientist at Mystic River Watershed Association, said of the run, "the Herring Monitoring Program has been one of the most successful volunteer programs MyRWA has had.  The construction of the new fish ladder has allowed this interesting opportunity for volunteers to view and monitor herring, and allowed herring passage to the Upper Mystic Lake to spawn easily for the first time. It's an exciting new program, and we are happy with the first year's results."

The Herring Monitoring Program would not be possible without permission from and collaboration with the Massachusetts Department of Conservation and Recreation, the Massachusetts Division of Marine Fisheries and generous financial support from Federal Realty Investment Trust. This Program allowed local residents, including children of all ages, to be witness to this ancient and inspiring migration. The Mystic River Watershed Association will continue the Herring Monitoring Program next year, and new volunteers are encouraged to sign-up as fish counters. Learn more about the Herring Monitoring Program at

Why Monitor River Herring?

Monitoring river herring is especially important in light of the species’ recent population decline.  Over the last decade, coastal landings of both river herring species averaged a little more than one million pounds—indicating a decline of more than 98 percent when compared to averages from 1950 to 1970.  Between 2000 and 2010 Alewife counts in Massachusetts’ Monument and Mattapoisett Rivers—two of the state’s most significant herring runs—plummeted almost 85 and 95 percent respectively.  River herring population decline is associated with many factors including pollution, by-catch (unintentionally caught fish), lack of spawning habitat, habitat degradation, and dams.

With regard to by-catch there is some very good news for river herring. Steps taken in June 2012 by the New England Fishery Management Council to regulate the industrial Atlantic herring fishing fleet will help protect this small forage fish. By requiring new permit conditions for large scale mid-water trawlers, the Council will help commercial fisherman strike a better balance between the target fish and those species that are simply caught up in their nets. New permit conditions include independent observers on board, a limit to dumping, a river herring catch cap and a more accurate weighing of fish caught by these massive operations. These actions taken by the New England and other east coast Fishery Councils will go a long way to help restore river herring populations.