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upcoming events

Oct 25
Friends of the Mystic River Annual Fall Cleanup, 9am-1pm
Condon Band Shell, Rt. 16, Medford

Oct 28
Hearing on the impact of the Silver Maple development, 3-5pm
831 Massachusetts Avenue, Cambridge

Oct 28
Wynn Resorts Presentation, 7PM
Winthrop St. Function Hall, Tufts University, 51 Winthrop Street, Medford

Nov 18
Friends of the Malden River meeting, 6:30-8PM

Dec 2
Committee Meeting, 7-9PM
Tufts University, Lincoln Filene Center, Rabb Room


MyRWA launched the third year of the Herring Monitoring Program in April 2014. This data is used to estimate the total herring run size in the Mystic River and is shared with the Massachusetts Division of Marine Fisheries to help inform trends across the State.  MyRWA would like to thank the DCR, Medford Boat Club and of course all the monitors for supporting this program!


Herring is a type of fish. The Mystic River Watershed supports two species of herring: Alewife (Alosa psuedoharenous) and Blueback Herring (Alosa aestivalis). Both species, collectively called river herring, are anadromous. This means they spend most of their lives at sea and return to rivers—like the Mystic—to spawn, or lay their eggs.


In colonial times and earlier, herring in the Mystic River were extraordinarily abundant.  But from the 1900’s until today a much smaller population of river herring is present. Since the dam has been rebuilt this is the first time that a fish ladder will be in place to allow an accurate count of herring.

According to the Herring Alliance some river herring runs on the Atlantic Coast have declined by 95% or more over the past 20 years. In 2006 the National Marine Fisheries Service designated river herring as a species of concern. Population decline may be associated with numerous factors including by-catch, habitat loss and degradation, water pollution, poaching, access to spawning habitat, and natural predators.


2014: 31,063 herring were counted from April 1 through June 26, 2014. Using modeling software provided by the Division of Marine Fisheries, the Mystic River herring run was estimated to be 239,059 +/- 37,288 herring.

2013: 23,635 herring were counted from April 1 through June 26, 2013. Using modeling software provided by the Division of Marine Fisheries, the Mystic River herring run was estimated to be 193,125 +/- 24,250 herring.

2012: 21,052 herring were counted from April 1 through June 23, 2012. Using modeling software provided by the Division of Marine Fisheries, the Mystic River herring run was estimated to be 198,932 +/- 18,062 herring. This was the first year of the Mystic River Herring Monitoring Program!

Click to enlarge




The Herring Monitoring Program will monitor herring swimming through a fish ladder to estimate run size. Counting will occur from April 1 – mid June following the Division of Marine Fisheries protocol.

The goal of the herring monitoring program is to collect valuable data about herring populations as they make their way up the Mystic River to reach their native spawning grounds and to educate the public about river herring.  We hope that through participation, volunteers will increase their understanding and stewardship of the Mystic River and the watershed.

Volunteers monitor river herring at the Mystic Lakes Dam fish ladder, counting fish and collecting data to estimate run size in the Mystic River. Previously the dam prevented river herring from reaching their native spawning grounds. In the past, a bucket brigade was assembled to hoist the fish over the dam. Thanks to the Upper Mystic Lake Dam Rehabilitation project, a new fish ladder allows passage for river herring.



Click the image below to identify herring.


MyRWA also monitors American Eel (Anguilla rostrata) passing through the Upper Mystic Lake Dam. Read more about eel monitoring here.



Volunteer to be a fish monitor!  No previous experience or knowledge is required. To find out more about this volunteer opportunity or the project, please email:


This program would not be possible without the support and collaboration with:




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